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Applied Developmental Psychology 24 (2003) 201–239
Findings from the Self-Sufficiency Project:
effects on children and adolescents of a program that
increased employment and income
Pamela Morris*, Charles Michalopoulos
Manpower Demonstration Research Corporation (MDRC), 16 East 34th Street, New York, NY 10016, USA
Accepted 1 April 2003
Abstract
This paper examines the effects on children of an antipoverty employment program for Canadian
welfare recipients called the Self-Sufficiency Project (SSP). The SSP made work pay better than
welfare by offering a temporary, but generous, earnings supplement to single parents who left welfare
for full-time employment. The SSP was tested using a rigorous random assignment research design.
While the SSP was found to increase employment and income for parents of children in every age
group, the effects of the program on the children themselves differed with their age. For very young
children, the SSP had no effect on children’s outcomes. For children in the middle childhood period at
follow-up, the SSP increased children’s cognitive functioning and health outcomes, but had no benefits
on their social behavior. For adolescents, the SSP increased minor delinquency and substance use. The
results are discussed in terms of their contribution to research and policy.
D 2003 Elsevier Science Inc. All rights reserved.
Keywords: Maternal employment; Income; Welfare; Poverty; Experiments
1. Introduction
A number of studies have examined the effects of welfare and employment policies on
the economic status of low-income parents. Less is known, however, about the effect on
0193-3973/03/$ – see front matter D 2003 Elsevier Science Inc. All rights reserved.
doi:10.1016/S0193-3973(03)00045-5
* Corresponding author. Tel.: +1-212-340-8880; fax: +1-212-684-0832.
E-mail address: [email protected] (P. Morris).
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239202
children of policies that encourage welfare recipients to work. The few studies that do exist
focus on elementary school-age children, leaving us relatively uninformed about the effects
of such policies on both adolescent and very young children (Gennetian & Miller, 2002;
Huston et al., 2001; McGroder, Zaslow, Moore, & LeMenestrel, 2000). This paper seeks to
add to this literature by looking at evidence from a demonstration project called the Self-
Sufficiency Project (SSP), a policy innovation that made work pay better than welfare by
offering a temporary, but generous, earnings supplement to selected single-parent welfare
recipients in Canada. This research informs both developmental research and policy, and is
especially timely given the policy context of changes at the federal and state level in
the area of welfare reform. While the SSP tested a policy change in the context of two
Canadian provinces, the similarity with the few most generous U.S. policies, along with the
similarity in welfare and economic context between the United States and Canada, provides
an appropriate backdrop for considerations regarding U.S. policy as well as developmental
theory.
Three features combine to make this study unique. First, the intervention studied in the
SSP had substantial effects on the employment—particularly full-time employment—
earnings, and income of single-parent welfare recipients who were studied (Michalopoulos,
Card, Gennetian, Harknett, & Robins, 2000). Second, the SSP was studied using random
assignment, in which individuals were assigned in a lottery-like process to either a
program group, which was offered the SSP supplement, or a control group, which was
not. Random assignment is often considered the most reliable means of determining the
effects of a new policy. Moreover, the random assignment design allows definitive causal
inferences about the effects of an incentive to work—and more tenuous statements about
the resulting effects of increases in maternal employment and income—on children than
has been typically addressed in nonexperimental work. Third, the SSP collected extensive
information on preschool children, school-age children, and adolescents. The SSP therefore
offers a rare opportunity to inform our understanding of how programs that increase
employment and income may affect children at different developmental periods. Although
other studies have had one or two of these features, the SSP is the only study to have all
three.
In this study, we examine the effects of the SSP program on children’s developmental
outcomes. While we do examine the effects of the SSP program on potential mediators of the
program, including both direct targets of the program such as employment and income, and
more intermediate mechanisms such as child care and parenting behavior, we do not directly
examine the pathways by which the effects occurred here. As discussed later, by focusing on
the direct impacts of the SSP program, we preserve the integrity of the experimental design of
the study and can confidently attribute any effects on children, or mediators examined, to the
program itself.
1.1. The effects of welfare and employment programs on children and families
The effects of welfare, employment, and antipoverty programs on children have been
studied in several random assignment studies. The Negative Income Tax (NIT), which was
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 203
studied experimentally in four cities in the United States from 1968 to 1982, provided a
guaranteed level of income for working poor families, although receipt of the NIT was not
contingent on work effort (Munnel, 1986; Office of Income Security Policy, 1983). The NIT
maintained or increased income, and it decreased parents’ work effort. For children, the NIT
was found to improve nutrition, early school achievement, and high school completion
(Mallar & Maynard, 1981; Salkind & Haskins, 1982).
In several recent studies of welfare reform programs in the United States, programs that
increased both employment and income also benefited children who were elementary school
age 2 to 3 years after the start of the programs (Morris, Huston, Duncan, Crosby, & Bos,
2001). The New Hope program increased employment and income among low-income
families in Milwaukee, WI by offering parents an earnings supplement, child care assistance,
and health insurance if they worked at least 30 hours per week. Teachers reported that boys in
the New Hope program were performing better academically and behaviorally in school than
comparable boys in a control group, although parent reports did not reveal significant
differences in program and control group children (and positive effects were not found for
girls; Bos et al., 1999; Huston et al., 2001).
The Minnesota Family Investment Program (MFIP; Knox, Miller, & Gennetian, 2000)
also increased both employment and income among welfare recipients in urban counties in
Minnesota in part by offering them financial incentives to work. Results from the MFIP
suggest that elementary school-age children benefit when their parents work part time and
their income increases (Gennetian & Miller, 2002). But, the duration of income improve-
ment may make a difference. Comparisons between the MFIP and a program in
Connecticut that combined a supplement with a time limit suggests that the MFIP, with
more sustained income increases, had more pervasive effects on multiple domains of
children’s well-being than Connecticut’s program, which curtailed income gains with a time
limit (Gennetian & Morris, 2003). And, in contrast to the New Hope and MFIP findings,
results from the evaluation of the National Evaluation of Welfare-to-Work Strategies
(NEWWS) suggest that programs that increase employment but not income do not have
consistent positive effects on early school-age children (Hamilton, Freedman, & McGroder,
2000; McGroder et al., 2000).
Data on older children are much weaker than for elementary school children because
most studies were not designed to assess the effects on older children. However, a
systematic meta-analysis of programs aimed to increase parental employment did find
small negative effects on adolescent school progress (Gennetian, Duncan, Knox, Clark-
Kauffman, & Vargas, 2002). These negative effects appear to be related to the increases in
responsibilities in caring for younger siblings that occurred when adolescents’ single parents
went to work.
1.2. Theoretical framework
Theories developed from sociology, psychology, and economics suggest that there are
several pathways by which children may be affected by welfare and employment programs.
Economic theory emphasizes the notion that employment and income can affect the resources
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239204
that families can provide for their children, which in turn can influence children’s
development (Becker, 1981; Coleman, 1988). Increased resources include both material
resources (that is, goods such as food or books) and nonmaterial resources (such as social
interactions with others, including teachers and peers) that parents provide for their children.
In this way, children are thought to benefit from parents’ increased income because this
increased income allows parents to invest more in their children’s development.
Psychology has emphasized instead the role of family functioning and parenting practices
that affect children’s well-being. Increased income may influence children’s development, for
example, by reducing parental stress and thereby changing the parent–child relationship
(Mcloyd, 1990; McLoyd, Jayartne, Ceballo, & Borquez, 1994).
1.2.1. Maternal employment
Maternal employment has been hypothesized to have both positive and negative effects on
children (Hoffman, 1989). In general, however, maternal employment has been found to have
few negative effects. There are two exceptions: maternal employment in the child’s first year
of life has been found to have negative effects, and boys have been found to be negatively
affected by their mothers’ employment (Baydar & Brooks-Gunn, 1991; Belsky & Rovine,
1988; Bronfenbrenner & Crouter, 1982; Brooks-Gunn, Han, & Waldfogel, 2002). In several
prior studies (Bronfenbrenner & Crouter, 1982; Desai, Chase-Lansdale, & Michael, 1989),
differences in the effects of maternal employment by social class have been observed, with
more negative effects of maternal employment for middle class as compared with lower
income families. Low-income children and children of single mothers have been found to
benefit from their mothers’ employment (Harvey, 1999; Moore & Driscoll, 1997; Vandell &
Ramanan, 1992; Zaslow & Emig, 1997). However, these effects may not be causal, as
differences between children of employed and nonemployed mothers appear to be due as
much to the differences in characteristics between employed and unemployed mothers as to
parents’ work status (Zaslow, McGroder, Cave, & Mariner, 1999).
While maternal employment seems to benefit low-income children, some factors may
reduce this effect. First, a high number of hours of employment early in a child’s life may be
associated with negative cognitive and achievement outcomes (Harvey, 1999). In a related
matter, extensive increases in employment without increases in income in the context of time-
limited welfare have been found to result in negative effects on school-age children (Morris,
Bloom, Kemple, & Hendra, in press). Moreover, maternal employment may be associated
with positive child outcomes only when women want to work (Alvarez, 1985; Farel, 1980).
In addition, research suggests that high-level, complex jobs may have positive outcomes for
children, while lower levels of employment may translate into negative outcomes (Parcel &
Menaghan, 1994, 1997). These studies raise the question whether moving mothers into full-
time, low-wage service employment will have positive effects on children.
1.2.2. Family income
In addition to increasing employment, the SSP was intended to increase family income,
with the long-term goal of moving families out of poverty. Research suggests that poverty can
negatively affect children’s functioning, especially if it occurs in early childhood and is
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 205
persistent (Duncan & Brooks-Gunn, 1997; Duncan, Brooks-Gunn, & Klebanov, 1994). The
negative influence of poverty may be more concentrated in children’s achievement and
academic functioning, rather than their behavior and health outcomes (Duncan & Brooks-
Gunn, 1997). As an antipoverty program, the SSP may therefore exert its strongest influence
on children’s achievement and school functioning and only secondarily affect the domains of
children’s behavior problems and health.
Both the resources provided to children and changes in family interactions may play a role
in the association between family income and children’s development, as poverty is
associated with fewer learning materials in the home and greater parental stress and more
insensitive parenting practices (Bradley & Caldwell, 1984; McLoyd et al., 1994; Smith,
Brooks-Gunn, Lee, & Klebanov, 1997; Sugland et al., 1995).
1.2.3. Mediators of employment and income: Child care, parenting, and parents’ emotional
well-being
Two sets of mediators have been identified in the literature as key intervening mechanisms
between changes in parents’ employment and family income and outcomes for children.
These include changes that may occur outside the child’s home—child care and children’s
activities—that parents’ use to structure children’s time as they engage in employment and to
pay for educational activities; and changes that occur within the parent–child relationship,
including parents’ emotional well-being and parenting behavior. Prior research on both
pathways is discussed below.
1.2.3.1. Child carze as a mediating factor. One pathway by which changes in employment
and income may affect children is through the use of child care and children’s participation in
after-school activities. For young children, compensatory education programs have been
found to benefit low-income preschool children, at least in the short term (Lazar &
Darlington, 1982; Lee, Brooks-Gunn, & Shnur, 1988; McKey et al., 1985). There are
benefits in cognitive and language skill development for children in low-income families
from high-quality care as compared with low-quality care (Burchinal et al., 2000; NICHD
Early Child Care Research Network, 2000; Peisner-Feinberg et al., 1999; Ramey et al., 2000;
Shonkoff & Phillips, 2000). In addition, formal, center-based child care is more beneficial to
cognitive development than home-based care when the two are of comparable quality
(NICHD Early Child Care Research Network, 2000). With regard to health outcomes, infants
who are placed in group child care arrangements have higher rates of contagious illnesses
than do infants who are cared for at home (NICHD Early Child Care Research Network,
2001, in press). The effects of child care (whether of high or low quality) on children’s social
behavior, however, are much less consistently positive or negative (NICHD Early Child Care
Research Network, 1998; Peisner-Feinberg et al., 1999).
For older children, emerging research suggests that formal after-school activities are
associated with positive outcomes for low-income children and children living in unsafe
environments (Pettit, Bates, Dodge & Meece, 1999; Posner & Vandell, 1994, 1999). It is
believed that these activities only help children when they provide a stimulating academically
focused environment, as well as protection against a deviant peer group.
1.2.3.2. Parents’ emotional well-being and parenting behavior . Family income and maternal
employment may also affect children through changes in parents’ emotional well-being and
parenting behavior. Financial strain has been found to negatively affect children through
marital conflict and parenting in two-parent families (Conger, Conger, & Elder, 1997) and
through depression and negative disciplinary practices in single-mother families (McLoyd et
al., 1994). Elder’s seminal work on economic hardship during the Great Depression identified
a link between job and financial loss and punitive, inconsistent parenting behavior (Elder,
1974, 1979; Elder, Liker, & Cross, 1984). Later work provided evidence that the relation
between economic changes and parenting were mediated by changes in parents’ emotional
well-being (like depression; see McLoyd, 1998 for a review). McLoyd’s work further
expanded this model for relevance to Black families (McLoyd, 1990), and provided a test
of this model among single-parent families, with findings suggesting that job loss, through
financial strain and psychological distress, affected parenting behavior and, ultimately,
adolescent well-being (McLoyd et al., 1994).
Notably, previous research on changes in income and employment has focused on the
negative impact of unemployment, job loss, and financial insecurity rather than whether
increases in income and entry into work can cause gains in children’s development in the
same way that job loss seems to undermine children’s development. However, the research
suggests that interventions aimed at removing the financial strain on the family may improve
parenting and children’s functioning (McLoyd, 1998).
1.2.4. Developmental differences
Child’s age may moderate the effects of maternal employment on children. As discussed
earlier, employment in the first year of a child’s life may be associated with more negative
child outcomes (Baydar & Brooks-Gunn, 1991; Brooks-Gunn et al., 2002), especially if it
involves many hours of work (Harvey, 1999). Spending long hours in nonmaternal care is
also associated with negative behavioral outcomes for young children (Currie & Thomas,
1995; Lamb, 1998; McLoyd, 1998), but high-quality care may help to deter some of these
negative effects (see Lamb, 1998).
Adolescent children and their younger school-age peers may be affected differently by
maternal employment. After-school arrangements are associated with positive outcomes
for both preadolescent and adolescent children, keeping them in structured care and away
from peers (Eccles & Gootman, 2002; Pettit et al., 1999; Posner & Vandell, 1994, 1999).
By contrast, adolescents may have difficulties if left alone after school and into the
evening hours as mothers take on off-hour and shift work, and maternal employment has
been found to be associated with reduced parental supervision and increased adolescent
delinquency among low-income families (Sampson & Laub, 1994). Adolescent children
may also be asked to take on greater household responsibilities as well as work when
their single mothers move into employment, and a high level of employment during
adolescence (particularly more than 20 hours of employment) has been linked with
children’s difficulties in school and increased drug and alcohol use (Burton, Brooks, &
Clark, 2002; Mortimer, Finch, Ryu, Shanahan, & Call, 1996; Steinberg & Dornbusch,
1991).
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239206
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 207
Child age has also been found to moderate the effects of family income on children.
Associations between poverty and child outcomes are stronger for preschool than for early-
school-age or older children. A longitudinal analysis has suggested that early childhood
poverty (when the child is age 0–5) is associated negatively with children’s completion of
schooling in adolescence, but that poverty from ages 6 to 15 is not (Duncan & Brooks-Gunn,
1997). This finding suggests that increasing income during the preschool years may be more
important for children’s outcomes than increasing income in adolescence.
1.2.5. Developmental differences in the combined effects of maternal employment and income
To our knowledge, there has been no research that attempts to examine the combined effects
of increasing maternal employment and family income across differing developmental periods.
While research has examined the moderating role of child age in the effects of maternal
employment and in the effects of family income, studies have not examined the effects of the
combined influence of the two, and how together they may affect younger, middle childhood
and adolescent children differently. The current study adds to our knowledge of developmental
processes by examining the effects of a program that increases both maternal employment and
family income on children of differing ages among long-term welfare recipient families.
Notably, as discussed in more detail in the Measures section, this work is complicated by the
fact that for differing ages of children, differing measures are needed to capture development-
ally appropriate constructs. While an analysis of the moderating role of child age would be
simplified by similar constructs collected across age groups, a recognition of developmental
change requires that measures change across the childhood age span.
1.3. The present study
The SSPwas a demonstration program designed to make work a viable alternative to welfare
for low-income parents, whose skills and experience would likely relegate them to low-paying
jobs. A group of about 6000 single parents in British Columbia and New Brunswick who had
been on welfare for at least a year were selected at random from the welfare rolls between
November 1992 andMarch 1995. In British Columbia, the SSP operated in the lower mainland,
which includes the Vancouver metropolitan area as well as neighboring areas to the north,
south, and east. In New Brunswick, the program operated in a region covering roughly the
lower third of the province, including the cities of Saint John, Moncton, and Fredericton.
Families who agreed to participate in the study were randomly assigned to either the program
group, which was offered the SSP supplement, or to a control group, which was not.
SSP’s financial supplement paid parents who left welfare and worked at least 30 hours per
week half the difference between their actual earnings and a target level of earnings.1 The target
earnings were set at Can$30,000 in New Brunswick and Can$37,000 in British Columbia a
year, although theywere adjusted slightly over time to reflect changes in the cost of living and in
1 Program group members could not qualify for the earnings supplement with jobs that were 100%
government-subsidized. Positions that were partially subsidized by the federal government or the province of New
Brunswick, however, were permitted.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239208
the generosity of welfare benefits. When the study began, the target earnings levels corre-
sponded roughly to U.S.$22,500 and U.S.$27,750, respectively. The SSP supplement varied
with individual earnings, rather than family income, and was therefore unaffected by family
composition, other family members’ earnings, or unearned income.2 Finally, supplement
payments were available for a maximum of 3 years, and only to sample members who initiated
SSP payments by finding full-time work within 12 months of entering the study.
In this analysis, we examine the effects of the SSP on children ages 3–18 at the time of a
survey administered about 3 years after parents entered the study (the ‘‘3-year follow-up
survey’’). Children are divided into three distinct developmental periods: (1) those who were
infants and toddlers at random assignment (and thus preschoolers by the end of the follow-up
period); (2) those who were preschool and early school age at random assignment (and thus
were in elementary school, i.e., middle childhood, by the end of the follow-up); and (3) those
who were preadolescent and adolescent at random assignment (and thus in adolescence by the
end of the follow-up period).
Random assignment reduced the risk that program and control groups differed system-
atically at the start of the study; therefore any systematic differences in children’s
functioning can be directly attributed to the program and not to any unmeasured
characteristic. Although any differences in children’s outcomes between the program and
the control groups are likely to be related to the increased employment and income
stemming from the program, the experimental research design is fully maintained only by
examining the effect of the program on each mediator or outcome (and not by examining
the relationships between mediators and outcomes). As in previous research on the effects of
experimental welfare and employment programs on children (Gennetian & Miller, 2002;
Huston et al., 2001), we focus here on the experimental effects of the offer of the SSP
supplement on the direct targets of the intervention (employment and income), on the key
mediating processes (child care, parenting, and parents’ emotional well-being), and on
children’s outcomes.
More specifically, we address the following questions: (1) How did the SSP affect parents’
employment, income, and material hardship (the primary targets of the SSP)? (2) How did the
SSP affect children’s cognitive, behavior, and health outcomes? (3) How did the SSP affect
children’s interactions and experiences in and outside the home (including child care,
children’s activities, their parents’ emotional well-being, and parenting behavior—potential
mediators of the effects of income and employment)?
1.4. The Canadian context
How relevant is the SSP to our understanding of the effects of welfare and employment
programs in the United States? Under the policy innovation tested in the SSP, the income of a
2 Thus, the SSP supplement formula does not penalize single parents who receive child support, marry, or find
a partner. However, because benefits from SSP do not increase with family size (and Income Assistance [IA]
does), SSP is relatively less generous than IA for larger families.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 209
typical parent with two children increased by about Can$400 per month, net of the welfare
benefits they would have forgone to receive the program’s supplement. This is very generous,
and more generous than many policies available to low-income families in either the United
States or Canada. However, there are a few policies that are similarly generous to the policy
tested under the SSP. The federal Earned Income Credit is very generous for certain
families—for example, it currently provides nearly U.S.$4000 to a parent with two children
who works full time at a minimum wage job. In addition, many states have implemented an
‘‘enhanced earnings disregard’’ as part of their welfare reform strategy, allowing welfare
recipients who work to keep more of their welfare dollars as their earnings increase and
disregarding a greater proportion of a welfare recipients’ earnings when calculating their
welfare benefit. In a few states, such as Connecticut and California, these earnings disregards
are now as generous or more generous than the SSP earnings supplement. In other states, low
welfare grants limit the income gains from earnings disregards and other policies, such as
time limits, and minimize a family’s ability to take advantage of them by discouraging
families from retaining a proportion of their welfare check as a supplement to their earnings
as they work. Finally, in some cases, a variety of benefits are available to families, but they
are administered from separate programs (like state EITC, food stamps, and child care
subsidies, for example), reducing the likelihood that any one family will take advantage of all
of the benefits available to them.
The Canadian context may affect the behavior of both the program and control groups in
the SSP—and is the background in which the experiment was tested. Canadian and U.S.
economic policies and outcomes have many similarities. The two countries offer similar types
of child care subsidies, and working mothers of young children make similar choices
regarding who cares for their children (Michalopoulos & Robins, 2000). Most single mothers
in both countries now work (Dooley, 1994; Meyer & Rosenbaum, 2000), and women in the
two countries earn similar amounts (Blackburn & Bloom, 1993). Federal governments in both
countries passed legislation that turned welfare from an entitlement program to a federally
funded block grant with considerable local discretion, although benefit levels in most
Canadian provinces tend to be higher than in much of the United States (Michalopoulos &
Robins, 2002). Although many U.S. and Canadian policies are similar, there are at least two
important differences. For example, Canadian safety net programs are more likely to be
universal rather than means-tested (Blank & Hanratty, 1993), and Canada has national health
insurance.
Because the SSP was conducted in both British Columbia and New Brunswick, the
SSP study has a distinct advantage that allows us to investigate how increases in employment
and income affect children in two different economic and cultural contexts. While the
Vancouver, British Columbia area (near Seattle) is an urban location with high average
wages, a high cost of living, and a high number of Asian immigrants, New Brunswick is
more heavily Catholic, more rural, and, as Canada’s only official bilingual province, has a
mix of English- and French-speaking citizens (Lin, Robins, Card, Harknett, & Lui-Gurr,
1998). The SSP has increased employment, earnings, and income by similar amounts in the
two provinces (Michalopoulos et al., 2000). If it has also affected children in similar ways,
this allows for the generalization of the results to a more diverse set of contexts.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239210
2. Method
2.1. Participants
The sample consisted of 3259 families and 5078 children (ages 3–18) who were in the
home at baseline and for whom data on children were collected at the 36-month follow-up.3
This sample included 1654 families and 2582 children in the program group and 1605
families and 2496 children in the control group. There were three age groups: (1)
preschoolers (ages 3–5 at 36 months after random assignment; n = 1043 children); (2)
children in middle childhood (ages 6–11 at 36 months after random assignment, n = 2158
children); and (3) adolescents (ages 12–18 at 36 months after random assignment, n = 1417
children). Baseline demographic information of the parents of children in the program and
control groups, and the full sample of parents of each age group of children are presented in
Table 1.
2.2. Procedures
Data were collected from a variety of sources. A baseline survey administered at the time
of random assignment provided background information on the families. Administrative
records provided information on recipients’ use of the welfare program and receipt of the
earnings supplement. Follow-up surveys at 18 and 36 months after random assignment were
used to gather information on recipients’ employment, earnings, income, hardship, and
expenditures. The 18-month survey was completed by approximately 93% of the research
sample, and the 36-month survey was completed by approximately 90% of the research
sample. There were three primary sources of information on family and child outcomes, all of
which were collected 36 months after random assignment: (1) parent surveys on all children
in the household, (2) language tests conducted with children between 4 and 7 years old at the
time of the 36-month interview and math tests conducted with children between 7 and 15
years old at that time, and (3) surveys conducted with children who were then age 10 and
older.
Notably, differing assessments of children’s outcomes were collected across the differing
child age groups. Measures were collected to assess key developmental constructs at differing
ages—for example, vocabulary acquisition for younger children, externalizing and intern-
alizing behavior problems in preschool and middle childhood children, and delinquency
behavior in adolescence. Across all child assessments, the response rate was 81% of the
eligible child study sample. However, the response rate was much lower for direct assess-
ments with the older children (64%), largely because older children were more likely to be
difficult to contact and more likely to refuse to participate in the study. Response rates were
3 Data were collected on children who were not in the home at baseline but who were there at the 36-month
follow-up. These children were excluded from the analysis sample, since those in the program group had not
received the full ‘‘treatment.’’
Table 1
Selected baseline characteristics of parents, by child age
Characteristic Middle Full sample
Preschool
Children
Childhood
Children
Adolescents Program
group
Control
group
Difference
Gender (%)
Female 99.31 97.88 95.85 97.10 97.38 � 0.03
Age (%)
19–24 50.50 20.74 0.24 23.12 23.60 � 0.05
25–29 28.51 31.00 11.52 23.49 23.91 � 0.42
30–39 19.70 40.99 64.40 40.86 40.57 0.29
40–49 1.29 7.04 21.36 11.32 10.99 0.33
50 or older 0.00 0.22 2.48 1.21 0.94 0.27
Marital status (%)
Never married 71.12 51.85 31.47 51.94 52.52 � 0.59
Divorced, separated,
or widowed
26.31 45.70 66.85 46.13 45.23 0.90
Completed education (%)
Less than high school 51.73 52.18 56.45 1.94 53.83 � 1.90
High school 39.76 36.42 32.03 37.07 34.83 2.24
Some postsecondary 8.51 11.40 11.53 10.90 11.34 � 0.44
In school at baseline 17.43 14.39 9.83 14.76 14.21 0.55
Recent welfare history
Number of months on IA in prior 3 years (%)
10–23 34.12 17.48 17.33 21.10 23.36 � 2.26
24–35 40.45 35.35 30.27 34.70 35.20 � 0.50
All 36 25.42 47.17 52.40 44.20 41.43 2.76
Average IA payment in
prior month (Can$)
871.49 876.10 869.38 854.58 851.41 3.17
Work history and labor force status
Ever had paid job (%) 93.37 93.36 95.45 94.62 93.33 1.29
Average years worked 4.69 6.31 8.70 6.79 6.73 0.06
Labor force status at baseline (%)
Employed 30 h/week 4.77 6.61 8.50 6.57 7.43 � 0.86
Employed < 30 h/week 8.45 13.77 13.79 12.96 13.37 � 0.40
Looking for work 20.08 21.37 22.61 21.24 22.99 � 1.74
Not employed/looking for work 66.70 58.25 55.09 59.22 56.21 3.01y
Activity-limiting conditions (%)
Physical problem 16.83 20.93 30.54 23.28 23.80 � 0.52
Emotional problem 4.67 6.32 9.75 7.92 6.11 1.81*
(continued on next page)
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 211
Characteristic Middle Full sample
Preschool
Children
Childhood
Children
Adolescents Program
group
Control
group
Difference
Emotional well-being (%)
At risk for depression 24.95 25.82 28.82 26.24 26.29 � 0.05
Children
Number of children under age 19 (%)
1 50.65 37.62 32.16 48.21 49.37 � 1.17
2 35.12 42.06 40.42 36.13 34.73 1.40
3 or more 14.23 20.32 27.43 15.67 15.89 � 0.23
Ethnic background (%)
First Nations ancestry 9.73 8.12 9.62 8.78 8.32 0.46
Asian ancestry 4.77 5.02 5.45 4.79 5.07 � 0.28
French-speaking 13.66 11.93 13.34 13.91 13.40 0.52
Immigration (%)
Not born in Canada 10.78 12.97 16.08 12.70 13.85 � 1.15
Immigrated last 5 years 3.57 2.07 3.13 2.54 3.25 � 0.71
Period of intake (%)
11/1992–10/1993 35.31 34.86 33.07 34.04 34.08 � 0.04
1/1994–3/1995 64.69 65.14 66.93 65.96 65.92 0.04
Province (%)
British Columbia 48.27 50.11 48.40 48.25 48.91 � 0.66
New Brunswick 51.73 49.89 51.60 51.75 51.09 0.66
Sample size
(total = 3259 families)
1011a 1836a 1252a 1654 1605 3259
Source: Calculations from the baseline survey and IA administrative records.
Sample sizes vary for individual measures because of missing values.a Because children of more than one age group may come from the same family, the total number of families
(3259) across the three age groups is smaller than the sum of the families in each of the age groups of children.y p<.10, two tailed test for differences between the outcomes for the program and control groups.
*p<.05, two tailed test for differences between the outcomes for the program and control groups.
Table 1 (continued)
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239212
similar in the program and control groups, providing a measure of confidence in the estimates
of program effects. Extensive nonresponse bias analyses suggested that survey respondents
and nonrespondents had somewhat different family characteristics. However, there was little
evidence that impacts of the program based on information about survey respondents (that
were available for both respondents and nonrespondents to the child surveys like data on
employment, welfare receipt, and income) were different than they would have been if all
families had responded to the survey (Morris & Michalopoulos, 2000).
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 213
2.3. Measures
2.3.1. Parental employment, income, and material hardship
2.3.1.1. Employment. Parental reports of employment were obtained from the 18- and 36-
month follow-up surveys. Because some interviews were conducted in the 35th month after
random assignment, complete data are available only for 34 months following random
assignment. In each interview, respondents were asked for earnings, hours worked per week,
and weeks worked per month for each job they had held since the prior interview. In tying the
incentive to full-time (30 hours of work per week), the program was intended to increase full-
time, and not part-time, employment. For this reason, program impacts on full-time
employment only are examined here, in addition to impacts on earnings. A parent was
considered to be working full time in a month if responses indicated working at least 30 hours
per week for at least one week in the month. Average monthly earnings were computed from
reports on hourly wages, hours worked per week, and weeks worked per month.
2.3.1.2. Income. Monthly income from welfare and SSP supplement payments were obtained
from administrative records from the Ministry of Human Resources in British Columbia, and
Human Resources Development—NewBrunswick, and SSP’s ProgramManagement Informa-
tion System (PMIS). Income was computed as the sum of earnings, welfare payments, and SSP
supplement payments. All dollar amounts reported are in Canadian dollars.
2.3.1.3. Material hardship. The survey included information on several aspects of material
hardship: (1) Food hardship: two questions addressed parents’ difficulties with obtaining food
in the last 3 months: (a) whether the parent had ever used a food bank to get food and (b)
whether there was a time the parent could not afford food; (2) Household/structural problems:
three questions addressing (a) whether the gas/hydro had been turned off in the last 3 months
because of an inability to pay the bills, (b) whether the parent currently had any structural
problems with the home (e.g., leaky roofs and broken windows), and (c) whether the parent
currently had any problems with things not working in their home (e.g., appliances, heating,
electricity, and plumbing); (3) Health care problems included two questions about whether
there was a time in the last 6 months when (a) a member of the family needed to go to the
doctor but could not afford to go, and when (b) a member of the family needed medication
but could not afford it.
2.3.2. Children’s cognitive performance
Two tests were administered to children, but the tests varied depending on the child’s age.
For both age groups, well-established measures available in both official Canadian languages
(English and French) were administered.4 For younger children, it was believed that changes
in income and employment might be reflected in children’s early vocabulary, and therefore
4 All surveys administered in Canada must be available in both English and French, limiting the choice of tests
available to administer to children.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239214
these children were administered a receptive vocabulary test. Older school-age children were
assessed with regard to their math skills, as no reading measure was available in both English
and French for administration to the school-age children (and it was believed that vocabulary
acquisition may be less sensitive to changes in employment and income than reading and
math skills for this age group). In addition, parents and children responded to several
questions about the child’s school performance.
2.3.2.1. PPVT-R score. Children ages 4–7 years were administered the Peabody Picture
Vocabulary Test—Revised (PPVT-R), a test of children’s receptive language ability.5 Raw
scores were converted to standard scores according to standards provided by the American
Guidance Service.
2.3.2.2. Math score. Amath skills test was administered to children ages 7–14 in Grades 2–7.
The test, which varied by the child’s grade level, consisted of 26 math problems for those in the
second grade and 34 items for those in Grades 3 and above. The test included a subset of items
from the Canadian Achievement Tests, Second Edition (CAT/2), a mathematics test developed
by the Canadian Test Centre that is administered annually in all provinces to approximately
300,000 students from Grades 2 up to the end of secondary school and college. The proportion
of correct items completed out of the total number of test items was computed for each child.
2.3.2.3. Academic achievement. Children’s functioning in school was assessed by means of
parent and child surveys for children of school age (6–18 years). Parents were asked about
children’s functioning in reading, writing, and math (for 6–15 year olds) or writing, math,
and science (for 15–18 year olds). Children ages 10–18 were asked about English, math, and
science. For each subject, functioning was ranked on a 5-point scale ranging from ‘‘not very
well at all’’ to ‘‘very well.’’ A measure of children’s average achievement was computed as
the average score across the three academic subjects. In addition, a dichotomous measure was
computed indicating whether the child scored below 3 (‘‘average’’) on any one of the
academic subjects to assess distributional as well as average effects, i.e., to determine if
average effects masked movement at the lower, more critical, portion of the distribution (cf.,
Gennetian & Miller, 2002).
2.3.3. Children’s behavior and emotional well-being
2.3.3.1. Behavior problems.Parents reported on children’s behavior for children up to age 11
using a scale developed for use in the National Longitudinal Survey of Children and Youth in
5 French-speaking children were administered the Echelle de vocabulaire en Images Peabody (EVIP), a test
comparable to the PPVT. Scores on the EVIP are not equivalent to scores on the PPVT (Marta Fahrenz, American
Guidance Service, personal communication, May 1999); therefore, the French- and English-speaking children
were analyzed separately. Unfortunately, the sample of children who chose to answer the test in French was too
small to allow an analysis of the impact of the SSP on children’s functioning on the EVIP. A total of 214 children
took the EVIP. These children were part of both the young preschool and middle childhood age groups.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 215
Canada (NLSCY). The NLSCY is a unique survey of Canadians from birth to adulthood, and
the measure of behavior problems has items similar to the Behavior Problems Index (a 28-
item scale; Peterson & Zill, 1986) used in many U.S. studies of the effects of welfare reform
programs (Morris et al., 2001). A slightly different set of items was asked of parents of 3- to
5-year-old children than of parents of children ages 6–11, but internal reliability was high for
both age groups (a = .87 for the 21 items for the 3–5 year olds and a = .92 for 27 items for
the 6–11 year olds). An average score was computed across the items (which were coded on
a 3-point scale ranging from ‘‘never/not true’’ to ‘‘often/very true’’). Items included both
internalizing and externalizing aspects of children’s behavior. Sample items included, ‘‘My
child is too fearful or anxious,’’ ‘‘My child cries a lot,’’ ‘‘My child steals at home,’’ and ‘‘My
child gets into many fights.’’
2.3.3.2. Positive social behavior. Parents reported on children’s positive social behavior for
children up to age 11 using a 5-item scale developed for the NLSCY that are similar to items
in the Positive Behavior Scale used in other welfare demonstration studies (Polit, 1996). As
with the behavior problems scale, a slightly different set of items was asked of the parents for
their 3–5 year old children than for their 6–11 year old children, but internal reliability was
good for scales for both age groups (a = .75 for the 3–5 year olds and a = .80 for the 6–11
year olds). Sample items include: ‘‘My child tries to help someone who is hurt’’ and ‘‘My
child comforts a crying child.’’ Scores on the total positive social behavior scale ranged from
1 (never) to 3 (often). The average score across the five items tapping children’s social
interactions with peers was computed.
2.3.3.3. School behavior problems. Parents of children in school (ages 6–18) were asked how
often in the past school year they were contacted by the school about their children’s behavior
problems in school. This item has been used in a number of recent welfare and work
demonstration studies (e.g., Gennetian & Miller, 2002). Scores ranged from 1 (none or one
time) to 3 (four or more times).
2.3.3.4. Frequency of delinquent activity. Children 10–18 years old were asked about the
frequency of a number of delinquent acts, using a subset of items from LeBlanc and
Tremblay (1988) used in the NLSCY. Example items included ‘‘Did you skip a day of
school without permission?’’ ‘‘Did you get drunk?’’ ‘‘Did you run away from home?’’
Items referred to the last 6 months, except for one item that asked about skipping school
in the last month. Children ages 10–14 were asked seven items (a = 0.78), while children
ages 15–18 were asked about a wider range of delinquent activity across 14 times,
including theft, starting fires, and using weapons (a = .72). Each was scored on a scale
of 1 (never) to 4 (5 or more times). The average frequency across seven items for the
10- to 14-year-olds and 14 items for the 15- to 18-years-old was computed for each
child.
2.3.3.5. Substance use. Children ages 12–18 were asked whether they currently smoked,
drank alcohol weekly, and had used drugs in the last 6 months (not including inhalants). Each
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239216
measure was binary (yes or no), and children who had engaged in the activity were scored as
100, while children who had not were scored as 0.
2.3.3.6. At risk for depression. Children ages 15–18 were asked the number of days in the
past week they had experienced each of 11 depressive symptoms taken from the Center for
Epidemiological Studies Depression (CES-D) scale (a = .80; Radloff, 1977). Given the high
internal reliability of the original scale, this shortened version was believed to provide a close
approximation of scores on the total scale. The items were scored on a scale ranging from 0
(rarely/never) to 3 (5–7 days) and were summed to obtain a total score, as in the original
development of the scale (Radloff, 1977). However, one item was deleted because it was
negatively correlated with the other items on the scale, leaving a total scale of 10 items.6
Because this scale has been validated as a dichotomous and not a continuous measure
(Radloff, 1977), a clinical cutoff was used. Previous research has identified a threshold (a
score of 16 out of 60 using the original 20 items) at or above which scores may be indicative
of clinical depression. A corresponding threshold (a score of 8 out of 30) was used for this
smaller subset of items. This scale demonstrated good internal validity, with a = .80.
2.3.4. Children’s health
2.3.4.1. General health. Four items from the NLSCY addressed parental reports of children’s
health for all children in the sample (ages 3–18). Sample items included: ‘‘He doesn’t get sick
often’’ and ‘‘She seems less healthy than other children you know.’’ Items were asked on a 5-
point scale ranging from 1 (false) to 5 (true), with 3 being ‘‘sometimes false/sometimes true.’’
Items were rescored such that high scores indicated better health. An average score across the
four items was constructed to measure children’s general health. This scale had a moderate
internal reliability, with a = .62.
2.3.4.2. Long-term health problems. Parents were asked to report whether their children had
any long-term health problems that had lasted or would last 6 months or more, that had been
diagnosed by a health professional, and that limited the child’s participation in activities.
These problems included allergies, asthma, bronchitis, kidney problems, heart diseases,
epilepsy, cerebral palsy, mental handicap, and learning and emotional problems.
2.3.5. Parental emotional well-being
2.3.5.1. At risk for depression. As with the adolescent children, parents were asked about the
number of days in the last week they had experienced each of 11 depressive symptoms from
6 While children were asked about 11 depressive symptoms, one item detracted from the internal consistency
of the scale. The item ‘‘Everything I did was an effort’’ was negatively correlated with the total score and the other
items. It was suspected that some children interpreted this item to mean, ‘‘I put effort into everything I do’’ and
thus scored it differently than would be expected. Therefore, only 10 items were included in the score of
depression.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 217
the widely CES-D scale (Radloff, 1977). Again, the high internal reliability of the original
scale made this reduced number of items appear sufficient to assess depressive symptoms.
The items were scored on a scale ranging from 0 (rarely/never) to 3 (5–7 days) and summed
to obtain a total score (a = .83), as in the original scoring (Radloff, 1977). As discussed
earlier, previous research has identified a threshold (a score of 16 out of 60 on the 20-item
scale) at or above which scores may be indicative of clinical depression. A corresponding
threshold of 9 (out of 33) was computed to measure parental risk for depression for this
smaller set of 11 items.
2.3.5.2. Parenting behavior. Parenting behavior was assessed via both parental and child
reports using scales developed for use in the NLSCY. Parents were asked one set of questions
about each of their 3- to 14-year-old children, and a different set of questions about each of
their 15- to 18-year-old children, to address the differing parenting challenges of younger and
older children. Children who were 12–18 years old were asked to assess their parents’
behavior using the set of questions asked of parents of 15–18 year old children. All items
were answered on a 5-point scale ranging from ‘‘never’’ to ‘‘many times each day.’’
For questions asked of parents of children ages 3–14, a principal components factor
analysis with varimax rotation suggested that the items tapped three distinct factors: (1) warm
parenting (a = .77), (2) negative parenting (a = .80), and (3) consistent discipline (a = .65;
see Table 2). For the items reported by parents of 15- to 18-year-olds and for the 12- to 18-
year-old child report items, two distinct factors: (1) authoritative parenting (a combination of
warmth, democratic, and limit-setting parenting; Baumrind, 1971; Maccoby & Martin, 1983;
a = .86 for the parent report measure and a = .88 for the child report measure) and (2)
negative parenting (a = .77 for the parent report measure and a = .68 for the child report
measure; see Table 3). Items assessing parental monitoring were also administered but the
internal consistency of the scale was so low (a = .36 for the parent report monitoring scale
and .47 for the child report monitoring scale) that it was not used in later analyses. In a small
number of cases, items double-loaded on the factors. In general, items were considered as part
of the factor on which the item more highly loaded. In a few rare cases, items that loaded on a
particular factor were not included as part of the scale for theoretical reasons. For each of the
scales, total scores were computed by averaging the items on the scale.
2.3.6. Child care and children’s activities
2.3.6.1. Child care use. Parents were asked in the 36-month survey about the regular child
care arrangements they had used for the youngest child in the household over the past 18
months. Child care arrangements include before- and after-school programs, day care centers,
care by a relative in or out of the child’s home, and care by a nonrelative in or out of the
child’s home. Parents could indicate that their children had multiple care arrangements.
Separate variables were constructed for children’s participation in (1) formal care (that
included center care and before and after-school programs) and (2) informal care arrange-
ments (that included child care by a relative or nonrelative in or out of the child’s home).
Also, parents were asked the number of times the primary child care arrangement had
Table 2
Factor analysis results of parenting by parents of children aged 3–14 years
Item Warm
parenting
Negative
parenting
Consistent
discipline
Praise child .72
Talk/play together .76
Laugh together .73
Do something special together .67
Play sports together .66
Proportion of time praise child .49
Get annoyed when child disobeys .69
Tell child he is not as good as others .42
Proportion of time express disapproval .56
Get angry when punish child .60
Punishments depend on mood .43
Have trouble managing child .74
Punish for the same things .72
How well gotten along in past 12 monthsa .68
Child ignores punishments .57 � .44
Child gets out of punishments .35 � .65
Child gets away with things .33 � .67
Make sure child obeys .64
Punish when child does not stop behavior .77
Alpha for scale .77 .80 .65
Source: Calculations from the 36-month follow-up parent survey.
Only factor items with loadings greater than or equal to |.30| are shown. Bolded factor loadings indicate items that
were used to create the respective scales. Except as otherwise noted, items were included on the factors on which
they most highly loaded. Responses for items ranged from 1 (never) to 5 (all the time). Exceptions are otherwise
noted.a Responses for this item ranged from 1 (very well, no problems) to 5 (not well at all, constant problems).
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239218
changed in the last 6 months (excluding periods of care by themselves), which provided a
measure of frequent child care changes for children who changed child care arrangements two
or more times in the last 6 months.
2.3.6.2. Children’s after-school activities. Parents of children ages 6–14 were asked about
their children’s participation in activities in the past year. Children ages 12–18 were also
asked about their own participation in activities. Four different activities were addressed: (1)
sports involving teaching or instruction (apart from physical education in school); (2) sports
without a coach or instructor; (3) lessons in music, art, or other nonsport activities (outside of
school); and (4) clubs, groups, or community programs with adult leadership. Responses were
scored on a 1–4 scale ranging from ‘‘about every day’’ to ‘‘rarely.’’
2.3.6.3. Frequency of doing household chores.Children ages 12–18 were asked the frequency
with which they did regular family chores or carried out responsibilities, such as doing
housework and caring for younger siblings. Responses ranged from 1 (never) to 5 (about every
day).
Table 3
Parenting factor analysis results of parenting for children aged 12–18 years
Parent behavior Parents of children 15–18 years old Children 12–18 years old
Authoritative Negative Monitoringa Authoritative Negative Monitoringa
Smile at child .73 .74
Praise child .76 .70
Listen to child .65 .76
Solve problems with child .56 .70
Show appreciate child .77 .77
Speak well of what
child does
.79 .78
Proud of what child does .76 .77
Forget rules .50 .51
Nag about small things .65 .67
Keep rules when
suits myself
.41 .47
Get angry and yell .66 .63
Threaten punishment .71 .62
Punish depending
on mood
.61 .66
Hit or threaten to hit .52 .45
Know what child
is doing
.39 .44 .44 � .35
Tell child when to
be home
.69 .34 � .59
Find out misbehaviorb .40 .26 .33 � .45
Let child go out � .62 .77
Repeated punishmentc .58 .38 N/A N/A N/A
Get along with childc,d .47 N/A N/A N/A
Alpha for scale .86 .77 .36 .88 .68 .47
Source: Calculations from the 36-month follow-up parent survey and the 36-month follow-up child survey.
Only factor items with loadings greater than or equal to |.30| are shown. Bolded factor loadings indicate items used
to create the respective scales. Items were included on the factors on which they most highly loaded. Responses
for items ranged from 1 (never) to 5 (very often) unless noted otherwise.a Monitoring scale was not internally consistent and was dropped from analyses.b Item not included on the negative parenting scale to be consistent with a priori theory.c Items used only in the 36-month follow-up parent survey; not included in the child surveys.d Responses ranged from 1 (very well, no problems) to 5 (not well at all, constant problems).
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 219
2.3.6.4. Employment.Children ages 15–18were askedwhether they were working for pay and,
if so, the number of hours per week. These items were used to determine the proportion of
children who are working, and the proportion of children workingmore than 20 hours per week.
2.4. Analysis strategy
Impacts of the program were estimated as the difference in average outcomes for the
program and control groups. Because families were randomly assigned to program and control
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239220
groups, any difference between the two groups can be reliably attributed to assignment to the
program. Sample attrition did not make the program and control groups dissimilar on baseline
characteristics (see Table 1).7 The standard errors on the measures analyzed at the level of the
child (rather than the family) were adjusted for the shared variance between siblings in the
same family, using the standard errors developed by White (1980). This adjustment allows for
nonindependence among sample members that may arise for any reason, including that which
arises because children come from the same family, neighborhood, or province. Two-tailed
tests with an alpha of .10 were used to test for the significance of program impacts. This alpha
is equivalent to a one-tailed test at p< .05, which is appropriate for assessing program effects.
This is the procedure used in previous studies of the effects of welfare and employment
programs on children (Gennetian & Miller, 2002; Huston et al., 2001).
Tables of the effects of the program contain the unadjusted means in the program and
control groups, the difference between the mean levels in the two groups, and the effect size of
the difference. Effect sizes were computed by dividing the difference between the program and
control groups by the standard deviation in the control group under consideration. As indicated
earlier, because the experimental design of the study is only maintained by examining each
outcome in a separate analysis of treatment effects, mediating analyses are not conducted here.
3. Results
3.1. Receipt of the supplement and impacts on employment, Income Assistance (IA) receipt,
and income8
As shown in Table 4, just over one-third of the program group members found full-time
employment during the year after random assignment and received at least one supplement
payment. By 12 months after random assignment, the SSP had doubled full-time employ-
ment, from about 14% of the control group to about 28% of the program group (for a
difference of 14 percentage points between program and control groups; p< .01). In the
second half of the follow-up period, the difference between the program and control group
levels on full-time employment diminished somewhat to about 10 percentage points, but was
still significant (p< .01). This reduction in program impact was largely due to increases in
employment by the control group, rather than declines in the employment rates of the
program group. Over the 36-month follow-up period, 51.6% of parents in the program group
7 Analyses were conducted controlling for a small set of baseline characteristics in estimating the effects of the
program. The impact estimates and standard error of the estimates did not change appreciably; therefore, the
unadjusted impact estimates are presented here.8 For a greater discussion of the effects of the SSP on adults’ economic outcomes, see Michalopoulos et al.
(2000). Results presented in Table 4 differ from those presented by Michalopoulos et al., because some sample
members did not complete any of the child components and therefore were not included in the tabulations shown in
Table 4.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 221
worked full-time at some point, compared to 38.8% of parents in the control group, a
significant effect (p < .01).
Combined earnings and supplement payments produced much higher income on average
for families in the program group than families in the control group. As is shown in Table 4,
parents in the program group earned about Can$90 more per month than parents in the
control group (p< .01). Although they received about Can$80 per month less in income
from IA (p< .01), they received Can$150 per month in SSP supplement payments (p< .01).
The program impacts on the percentage of parents employed full time and income persisted
into the 6-month period prior to the interview (see Table 4 for impacts on employment and
income 6 months prior to interview for total sample; differences between program groups,
ps < .01).
In terms of program impacts on hardship, the SSP significantly decreased the proportion
of families using food banks or reporting that they could not afford food at the time of the
36-month interview (p < .05). However, there were no significant differences in the
proportion of families reporting household or structural problems or problems with health
care.
Only minor differences in impacts on adult economic outcomes were found for parents of
the three age groups of children. For parents of children in all three groups, about one-third of
families in the SSP group took up the supplement. And for all three groups, the SSP
significantly increased employment, earnings, and income (p < .01).
3.2. Impacts on children9
3.2.1. Impacts for preschool children
Impacts on younger children’s developmental outcomes are presented in Table 5. Children
in the control group had an average score of 91 on the PPVT-R test, which corresponds to a
percentile score of 27. There were no significant program impacts on PPVT-R scores for these
children.
Parents were asked about their children’s social behavior, emotional well-being, and health.
As can be seen in Table 5, there were no significant impacts in any of these areas. Analyses
were conducted to examine the impact of the SSP separately on internalizing and externalizing
dimensions of behavior. No significant effects of the program were found for either of these
two subscales of children’s behavior.
9 Given previous research on the differing effects of welfare and employment programs on boys and girls
(Huston et al., 2001), analyses were conducted to examine whether there were any significant differences in
impacts on child outcomes for boys and girls. While in some cases effects on girls were more pronounced than for
boys, differences in impacts were generally not statistically significant. Therefore, differences by gender were not
discussed in this paper. Differences in impacts for each of the three age groups was also examined for the two
provinces examined in this study: New Brunswick and British Columbia. Differences in impacts for the two
provinces were extremely rare, suggesting that the program had a similar effect on children’s outcomes in the two
different contexts.
Table 4
SSP summary of impacts on economic outcomes for families over the 36-month follow-up period
All families Families with preschool children
Program
group
Control
group
Difference
(impact)
Effect
size
Program
group
Control
group
Difference
(impact)
Effect
size
Received SSP
supplement (%)
35.91 36.11
Full-time employed,
Month 6
17.78 11.03 6.75** 0.22
Full-time employed,
Month 12
27.80 13.5 14.2** 0.42
Full-time employed,
Month 34a28.48 18.44 10.04** 0.26
Employment, earnings, and income, Months 1 to 34a
Ever full-time
employedb (%)
51.57 38.75 12.82** 0.26 53.14 36.49 16.66** 0.35
Monthly earnings
(Can$)
310.44 219.38 91.06** 0.23 298.78 181.78 117.01** 0.33
Monthly IA
income (Can$)
645.43 726.14 � 80.70** � 0.24 666.99 741.17 � 74.18** � 0.22
Monthly SSP
income (Can$)
152.14 0.00 152.14** 0.00 146.00 0.00 146.00** 0.00
Total income (Can$) 1113.22 957.33 155.89** 0.43 1119.82 928.84 190.98** 0.55
Employment and income 6 months prior to interview
Full-time employed (%) 33.98 23.86 10.12** 0.24
Monthly pre-tax
income (Can$)
1619.53 1443.03 176.50** 0.21
Expenditures and hardship, at 36 months
Food bank/not
afford (%)
35.27 40.76 � 5.49** � 0.11
Household
problems (%)
20.87 22.90 � 2.02 � 0.05
Health care
problems (%)
31.82 33.06 � 1.24 � 0.03
Sample size 1654 1605 3259 493 518 1011
Families with middle childhood children Families with adolescent children
Program
group
Control
group
Difference
(impact)
Effect
size
Program
group
Control
group
Difference
(impact)
Effect
size
Received SSP
supplement (%)
36.85 34.47
Employment, earnings, and income, Months 1 to 34a
Ever full-time
employedb (%)
52.93 39.35 13.58** 0.28 48.07 35.87 12.20** 0.25
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239222
Families with middle childhood children Families with adolescent children
Program
group
Control
group
Difference
(impact)
Effect
size
Program
group
Control
group
Difference
(impact)
Effect
size
Employment, earnings, and income, Months 1 to 34a
Monthly earnings
(Can$)
320.15 219.38 100.77** 0.24 296.78 218.94 77.84** 0.19
Monthly IA
income (Can$)
650.80 745.41 � 94.61** � 0.27 1103.48 741.53 � 82.71** � 0.23
Monthly SSP
income (Can$)
158.37 0.00 158.37** 0.00 144.12 0.00 144.12** 0.00
Total income (Can$) 1133.97 974.85 159.12** 0.41 1103.48 979.44 124.04** 0.35
Sample size 939 897 1836 647 605 1252
Source: Calculations from the baseline survey, IA administrative records, the 18-month follow-up core survey, and
the 36-month follow-up core survey.
Rounding might cause slight discrepancies in sums and differences. Sample sizes may vary for individual items
because of missing values.a Although information on employment comes from the 36-month follow-up core survey, some sample
members were interviewed as early as month 35, so that the valid information on employment and earnings is
available through month 34 only. Therefore, results related to employment and earnings are shown only through
34 months.b Full-time employment is defined as working 30 hours or more per week in at least one week during the
month.
**p < .01 for program versus control group.
Table 4 (continued)
Table 5
SSP impacts on child outcomes for the preschoolers at the 36-month follow-up
Outcome Program group Control group Difference (impact)a Effect size
Cognitive functioning
PPVT-R score 92.18 91.32 0.86 0.05
Sample size 403 425
Behavior and emotional well-being
Behavior problems 1.48 1.48 0.00 0.01
Positive social behavior 2.51 2.53 � 0.03 � 0.06
Sample size 497 535
Health
Average health 4.01 4.05 � 0.04 � 0.05
Any long-term problems (%) 25.60 27.43 � 1.83 � 0.04
Sample size 503 540
Source: Calculations from the baseline survey, the 36-month follow-up parent survey, and the PPVT-R.
Rounding may cause slight discrepancies in sums and differences. Preschool children were ages 3–5 at the 36-
month follow-up. Standard errors were adjusted to account for shared variance between siblings.a Differences were tested but all were nonsignificant.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 223
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239224
3.2.2. Impacts for middle childhood children
For the middle childhood children, effects on cognitive outcomes were consistent across
parents’ reports and tests, but small (see Table 6). Children in the program group scored
significantly higher on a math test than their peers in the control group (with an effect
size = 0.14), and mothers in the program group rated their children higher on average
academic performance in school than did mothers in the control group (effect size = 0.11).
There were no significant program impacts on any of the measures of children’s behavior
(see Table 6). Analyses were conducted to examine the impact of the SSP separately on
internalizing and externalizing dimensions of behavior. No significant effects of the program
were found for either of these two subscales of children’s behavior. However, according to
parents’ reports, children in the program group were in better health (effect size = 0.11) and
were slightly less likely to have long-term health problems than children in the control group
(effect size =� 0.09). For example, 37% of children in the control group were reported to
have long-term health problems compared to 32.4% of children in the program group.
3.2.3. Impacts for adolescents
Table 7 presents the impacts on outcomes for the adolescents. Small significant unfavor-
able effects for the older children were found in two of the four measures of children’s school
functioning. Mothers in the program group reported significantly lower average school
Table 6
SSP impacts on child outcomes for the middle childhood children at the 36-month follow-up
Outcome Program group Control group Difference (impact) Effect size
Cognitive functioning
PPVT-R score (ages 6–7) 93.21 90.78 2.43 0.13
Sample size 293 292
Math score (ages 7–11) 0.56 0.52 0.04* 0.14
Sample size 699 622
Average achievement 3.71 3.61 0.10* 0.11
Below-average, any subject (%) 22.84 25.65 � 2.81 � 0.06
Sample size 1015 982
Behavior and emotional well-being
Behavior problems 1.42 1.43 � 0.01 � 0.03
Positive social behavior 2.58 2.59 � 0.01 � 0.02
Sample size 1111 1047
Health
Average health 4.11 4.02 0.09* 0.11
Any long-term problems (%) 32.43 36.98 � 4.55* � 0.09
Sample size 1109 1041
Source: Calculations from the baseline survey, the 36-month follow-up parent survey, the PPVT-R, the math skills
test.
Middle childhood children were ages 6–11 at the 36-month follow-up. Standard errors were adjusted to account
for shared variance between siblings.
*p < .05, two tailed test for differences between the outcomes for the program and control groups.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 225
achievement for their children than did mothers in the control group, although there were no
significant program–control differences in the proportion of parents reporting that their
children were performing below average in school (see upper portion of Table 7). Nearly 19%
of children in the program group said they were below average in at least one subject in
school, compared to about 14% of the control group (p< .05). On the other hand, there were
no significant differences between the two groups on self-reported average achievement or on
the math skills test, the one objective measure of their academic performance.
Results on older children’s problem behaviors were more consistent with expectations.
While there were no differences in adolescents’ risk of depression, the SSP significantly
Table 7
SSP impacts on child outcomes for adolescents at the 36-month follow-up
Outcome Program group Control group Difference (impact) Effect size
Cognitive/academic functioning
Math score (ages 12–14) 0.45 0.46 � 0.01 � 0.03
Sample size 280 281
Average achievement 3.43 3.54 � 0.11y � 0.11
Below-average, any subject (%) 32.61 32.39 0.22 0.00
Sample size 726 673
Average achievement 3.50 3.57 � 0.07 � 0.09
Below-average, any subject (%) 18.91 14.26 4.65* 0.13
Sample size 512 470
Behavior and emotional well-being
Parental report
School behavior problems 1.40 1.34 0.06y 0.09
Sample size 740 677
Adolescent report
Delinquent activity, 12–14 years 1.35 1.38 � 0.03 � 0.06
Delinquent activity, 15–18 years 1.40 1.34 0.07* 0.21
Smoking (%) 26.52 22.13 4.39y 0.11
Drinks weekly or more (%) 8.91 4.65 4.27** 0.20
Drug use (%) 18.63 14.34 4.29y 0.12
Risk for depression, 15–18 years (%) 45.74 47.14 � 1.39 � 0.03
Sample size 568 509
Health
Average health 4.10 4.13 � 0.04 � 0.05
Any long-term problems (%) 38.99 38.11 0.88 0.02
Sample size 576 530
Source: Calculations from the baseline survey, the 36-month follow-up parent survey, the math skills test, and the
36-month follow-up child survey.
Adolescents were ages 12–18 at the 36-month follow-up. Rounding may cause slight discrepancies in sums and
differences. Standard errors were adjusted to account for shared variance between siblings.y p < .10, two-tailed tests for differences between the outcomes for the program and control groups.
* p < .05, two-tailed tests for differences between the outcomes for the program and control groups.
* * p < .01, two-tailed tests for differences between the outcomes for the program and control groups.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239226
increased the use of tobacco, alcohol, and drugs by about 4 percentage points (for smoking,
p < .10; for weekly alcohol use, p< .01; for drug use, p< .10, all based on two-tailed tests).
The SSP also increased the frequency of delinquent activity for older children (ages 15–18;
p < .05) but not for their younger peers (ages 12–14). Post hoc analyses conducted at the item
level suggested that the SSP significantly increased involvement in minor delinquent activity,
such as staying out late or all night, but not major delinquent activity, such as stealing,
carrying weapons, and involvement with police. There were no significant differences
between program and control groups on measures of older children’s health.
3.3. Impacts on child care and children’s activities
Findings on child care and after-school activities are presented in Table 8. Recall that the
36-month follow-up interview collected information on child care arrangements for only the
youngest child in the family for the period between the 18-month and 36-month interviews.
Therefore, results reflect impacts of the program for children in the three age groups who
were also the youngest children in the family. Information on children’s activities, on the
other hand, was gathered for all children in the household who were age 6 and older, so all
children were included in the analyses on these measures.
As indicated in Table 8, mothers of the preschool and middle childhood children in the
program group reported greater use of child care than mothers in the control group. For the
preschoolers, the SSP significantly, albeit modestly, increased both formal care (p< .01)
and informal (home-based) child care arrangements (p< .05). However, the SSP also
slightly increased the instability of child care (p< .10). For children in middle childhood,
mothers in the program group reported slightly more use of informal child care (p < .10)
and after-school activities (p < .10) than did mothers in the control group. However, there
were no program–control differences in the proportion of children having used formal care
arrangements.
For the adolescents, there were no significant differences between the program and control
groups in children’s after-school activities, as reported by both parents and adolescents, or in
Notes to Table 8:
Source: Calculations from the 18-month follow-up core survey, the 36-month follow-up core survey, and the 36-
month follow-up parent and child surveys.
Rounding may cause slight discrepancies in sums and differences. Sample sizes may vary for individual items
because of missing values.a The child care participation data are for children at the 36-month follow-up who were also the youngest
children in the family. All child care participation data are for the 18 months prior to the 36-month follow-up
interview.b These measures were assessed separately for each child in the family. Standard errors were adjusted to
account for shared variance between siblings.y p < .10, two-tailed tests applied to differences between the outcomes for the program and control groups.
* p < .05, two-tailed tests applied to differences between the outcomes for the program and control groups.
** p < .01, two-tailed tests applied to differences between the outcomes for the program and control groups.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 227
child care arrangements. However, the SSP increased children’s involvement in household
chores (p< .10). While there was no significant program impact on the proportion of
adolescents working for pay at the time of the 36 month follow-up interview, the SSP
Table 8
SSP impacts on child care and children’s activities
Preschoolers Middle childhood children
Program
group
Control
group
Difference
(impact)
Effect
size
Program
group
Control
group
Difference
(impact)
Effect
size
Child care for youngest childa
Any child care (%) 62.70 50.94 11.76** 0.23 45.43 39.97 5.46y 0.11
Any center care (%) 29.46 21.56 7.90* 0.19 8.52 7.03 1.49 0.06
Any informal child
care (%)
43.51 36.12 7.40* 0.15 36.91 31.73 5.18y 0.11
Changed care 2+
times (%)
5.95 3.24 2.71y 0.15 3.31 2.06 1.25 0.09
Sample size 370 371 634 583
Children’s activities (parental report)b
Any activity at least
once per week (%)
96.95 95.42 1.53y 0.07
Sample size 1115 1048
Adolescents
Program
group
Control
group
Difference
(impact)
Effect
size
Child care for youngest childa
Any informal child
care (%)
3.69 5.51 � 1.81 � 0.08
Sample size 379 345
Children’s activities (parental report) (ages 12–14)b
Any activity at least
once per week
91.53 92.35 � 0.82 � 0.03
Sample size 365 353
Children’s activities (adolescent report)b
Any activity at least
once per week
86.29 85.69 0.61 0.02
Frequency household
chores
4.03 3.92 0.11y 0.10
Sample size 568 510
Employment (adolescent report) (ages 15–18)b
Working (%) 35.49 35.17 0.33 0.01
Work 20 or more
hours per week (%)
15.04 8.13 6.90* 0.25
Sample size 292 236
Table 9
SSP impacts on impacts on family functioning
Preschoolers Middle childhood children
Program
group
Control
group
Difference
(impact)
Effect
size
Program
group
Control
group
Difference
(impact)
Effect
size
Parental functioning
At risk for depression (%) 33.18 36.76 � 3.58 � 0.07 42.08 36.82 5.26* 0.11
Sample size 435 461 819 795
Parenting behavior (parental report)a
Warm parentingb 3.94 4.00 � 0.06y � 0.12 3.63 3.64 � 0.01 � 0.02
Negative parentingb 2.14 2.15 � 0.01 � 0.02 2.10 2.09 0.01 0.01
Consistent disciplineb 3.88 3.85 0.03 0.04 3.81 3.83 � 0.02 � 0.03
Sample size 497 527 1119 1049
Adolescents
Program
group
Control
group
Difference
(impact)
Effect
size
Parental functioning
At risk for depression (%) 44.62 43.86 0.77 0.02
Sample size 573 539
Parenting behavior (parental report)a
Warm parenting,
12–14 yearsb3.42 3.39 0.03 0.04
Negative parenting,
12–14 yearsb2.08 2.07 0.01 0.02
Consistent parenting,
12–14 yearsb3.67 3.67 0.00 0.00
Authoritative parenting,
15–18 yearsb4.05 4.09 � 0.04 � 0.06
Negative parenting,
15–18 yearsb2.24 2.16 0.08y 0.14
Sample size 382 360
Parenting behavior (adolescent report)a
Authoritative parentingb 3.74 3.73 0.01 0.01
Negative/inconsistentb 2.34 2.39 � 0.05 � 0.07
Sample size 550 494
Source: Calculations from the 36-month follow-up parent survey and the 36-month follow-up child survey.
Rounding may cause slight discrepancies in sums and differences. Sample sizes may vary for individual items
because of missing values.a These measures were assessed separately for each child in the family. Standard errors were adjusted to
account for shared variance between siblings.b These items are rated on a scale of 1 (never) to 5 (many times each day).y p < .10, based on two-tailed tests applied to differences between the outcomes for the program and control
groups.
* p < .05, based on two-tailed tests applied to differences between the outcomes for the program and control
groups.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239228
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 229
increased the proportion of children working over 20 hours per week by 7 percentage points
(p< .05).
3.4. Impacts on parental emotional well-being and parenting behavior
Impacts on parental depression and parenting behavior for the three age groups of children
are presented in Table 9. For the preschoolers, approximately one-third of parents in both
program and control groups reported depressive symptoms that put them at risk for clinical
depression. Impacts on reported parenting behaviors were not common for parents of children
in this age group. Program group parents reported slightly less warm parenting than control
group parents (p < .10), but there were no significant differences on measures of negative
parenting and consistent discipline.
For middle childhood participants, the SSP increased the proportion of parents at risk for
depression by 5 percentage points (p < .05). Despite the small increase in parental depression
due to the SSP, the program did not significantly affect parental behavior as reported by
parents.
For parents of adolescents, program and control groups did not differ in their risk of
depression. In terms of reports of parenting behavior, program impacts were extremely rare.
The only difference that was statistically significant indicated more negative parenting among
program group than control group parents, as reported by parents of 15- to 18-year-old
children (p < .10). According to all the other parental and child report measures, however, the
SSP did not significantly influence parenting behavior among parents of adolescents.
4. Discussion
Although the SSP increased full-time employment and income for parents by a similar
amount for all three age groups of children, the pattern of significant effects of the SSP
on children varied considerably with the children’s age group.10 These findings suggest
that theoretical models of the effects of increases in maternal employment and family
income on children should include the moderating role of the developmental period of the
child. Moreover, the findings suggest that positive effects of increases in income and
employment appear to affect children through changes in the resources parents can
purchase for their children in terms of out-of-home environments rather than through
10 Post hoc analyses were conducted to address the extent to which differences in the effects of the programs
were due to differences in the background characteristics of families rather than the developmental challenges of
their children, as families with younger children have different background characteristics than families with older
children. While these analyses were hampered by the fact that different measures were collected for each of the
three age groups of children, they are suggestive. Using standardized child outcome measures created for each
domain of child functioning (cognitive/academic; behavior; health), multivariate analyses suggested that
developmental differences and not differences in family background characteristics accounted for the differences
in impacts between the age groups. Further information on this analysis is available from the authors.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239230
changes in parenting and psychological distress. These findings are discussed in greater
detail below.
4.1. Youngest children
The lack of program impacts on the cognitive, behavioral, or health outcomes of very
young children suggests a model of the offsetting effects of employment and income on this
age group. Given the strength of prior work on the positive effects of income for very young
children (Duncan & Brooks-Gunn, 1997), it seems most likely that the effects of employment
may indeed have been negative and offset by the benefits of income—resulting in neutral
effects overall for the youngest children. Some research has suggested negative effects of
maternal employment occur with increases in employment during the child’s first year of life
(Baydar & Brooks-Gunn, 1991; Belsky & Rovine, 1988; Bronfenbrenner & Crouter, 1982;
Brooks-Gunn et al., 2002), but other research has pointed to the positive effects of
employment for low-income children in particular (as compared to their middle income
peers; Desai et al., 1989). However, none of this research has examined the combined effects
of increases in income and full-time employment on young children’s development. Our
analyses of potential mediators of the effects of employment and income suggest that the
increased instability of care and reduced parental warmth may have resulted in mitigating any
positive effects of income on children. Alternatively, of course, neither the increase in income
nor employment may have affected these young children given the effects of poverty on
young children’s well-being (Duncan & Brooks-Gunn, 1997). However, this hypothesis has
less support from prior research.
Considering how young they were at the start of the program, and the fact that young
children’s attachment relationships may be forming during this period (Ainsworth, Blehar,
Waters, & Wall, 1978), it is noteworthy that the increases in full-time maternal
employment did not result in negative impacts on the youngest group of children when
accompanied by large increases in income, at least given the measures utilized in this
study. Of course, the fact that only a small proportion of the program group took up the
supplement (about one-third) means that any effects observed for this group of families
would have needed to be very large to offset the likely null findings for the remainder of
the program group and result in any average effects to be observed when the full program
group is examined.
4.2. Middle childhood children
For middle childhood children, the SSP had small positive impacts on cognitive and health
outcomes but not on behavioral outcomes. The benefits to health outcomes are more
surprising than those to cognitive outcomes given the availability of health insurance in
Canada. Since these findings could not be verified with assessments by a health professional,
we view them somewhat cautiously.
The positive effects on cognitive outcomes are consistent with research that suggests a
stronger association between poverty and children’s outcomes for cognitive outcomes than
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 231
for behavioral outcomes (Duncan & Brooks-Gunn, 1997). Since these children ranged from
preschool to early school age (3–8 years) at the beginning of the study (although they were
in middle childhood by the end of the study), these findings are also consistent with
research suggesting that income may play a stronger role for preschool than for older
school-age children (Duncan & Brooks-Gunn, 1997). In fact, post hoc analyses support this
conclusion in that significant increases in academic achievement for the younger children
rather than for the older children in this group were observed. Because the SSP increased
voluntary and not mandatory maternal employment, and such employment has been found
to benefit children (Alvarez, 1985; Farel, 1980), maternal employment may not have
resulted in negative effects for these children. For these children, who may be less sensitive
to maternal separations than their younger peers, the negative effects of maternal
employment may not have offset the positive effects of the increased income, and this
combination may have resulted in the observed benefits to children’s cognitive devel-
opment.
The findings shed some light on the pathways that may have led to the favorable impacts
for middle childhood children and suggest a stronger role for child care, as opposed to the
parenting practices, in impacts. Parents in the program group relied on after-school activities
to a greater extent than parents in the control group because they engaged in longer hours of
employment. The greater participation in such activities may explain, at least in part, the
benefits to academic and cognitive performance found for children in the program group
(Posner & Vandell, 1994, 1999). In contrast, the SSP program did not affect parental
functioning, suggesting that parenting was not the cause of the favorable impacts for middle
children, despite theoretical and empirical work to suggest that increases in income and
employment should benefit parenting behavior (McLoyd, 1990, 1994). Because the measures
were reported by parents rather than outside observers, however, it is unclear whether no
change in parenting behavior occurred or whether the measures were not sensitive enough to
capture such changes. Future research is needed to examine whether observational measures
of parenting yield the same result.
The SSP’s effects for middle childhood children are consistent with the random assignment
evaluations of New Hope (Bos et al., 1999; Huston et al., 2001) and MFIP (Gennetian &
Miller, 2002). Both of these programs increased maternal employment and family income,
and both improved academic functioning for children in the middle childhood group
(although New Hope’s effects were concentrated only among boys and not girls). These
programs did not find effects for self-reported parenting behavior for parents of middle
childhood children either. In the New Hope evaluation, the researchers suggested that the
increased after-school activities might explain some of the benefits to boys that were found
(Huston et al., 2001).11 In contrast, programs studied in the random assignment NEWWS that
11 In New Hope, sex differences emerged for control group outcomes as well as experimental program
impacts—with boys at higher risk of negative outcomes and for whom positive impacts of the program were
found. No such gender differences in control group outcomes were found in this study. Notably, no sex differences
in effects emerged in the evaluation of the MFIP either (Gennetian & Miller, 2000).
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239232
required parents to look for work or enroll in education programs in order to receive welfare
increased parents’ employment but did not increase their income. The programs generally
produced neither systematically positive nor systematically negative changes for elementary
school-age children (McGroder et al., 2000). The concordance of findings in the SSP program
and in the U.S. New Hope and MFIP studies yields greater confidence that programs that
increase voluntary employment and income benefit children in the middle childhood age
range. They further suggest that the programs benefit children by increasing children’s care
experiences rather than through changes in parenting practices.
4.3. Adolescent children
Prior research has focused primarily on the negative effects of maternal separations for
young children, but the findings reported here suggest that welfare and employment programs
might have their most negative effects on older children’s functioning. The findings are
consistent with those found across welfare and employment programs, on a limited set of
measures of school progress (Gennetian et al., 2002).
The results may suggest the importance of monitoring adolescents as parents move from
welfare into work. First, the SSP significantly increased parents’ full-time employment, but
did not increase children’s time in after-school arrangements. Moreover, the SSP increased
the type of delinquent behaviors (for example, staying out late rather than conduct problems)
that are more closely associated with lack of parental supervision (Pettit et al., 1999) than
with negative parent–child interactions (Dodge, Pettit, Bates, & Valente, 1995; Patterson,
1995; Patterson, DeBaryshe, & Ramsey, 1989). An ethnographic study conducted with
parents in the SSP found that many chose not to take up the supplement because of concern
with their adolescent children (Bancroft & Vernon, 1995). These parents may have foreseen
what others in the program group did not. Results in the SSP are also consistent with research
suggesting that a high level of employment in adolescence is associated with greater alcohol
use and delinquency (Mortimer et al., 1996; Steinberg & Dornbusch, 1991). In the SSP, more
older children in the program group than in the control group reported taking on greater
family responsibilities by doing chores, and they also engaged in higher levels of employ-
ment. Researchers have suggested that associating with young adults and taking on adult
responsibilities may encourage early adultification of adolescents, and, in some cases,
encourage them to engage in adult risk-taking behavior earlier (Burton et al., 2002; Mortimer
et al., 1996; Steinberg & Dornbusch, 1991).
These results suggest a very different model for the effects of the SSP on adolescent
children than for their younger peers. First, given nonexperimental research that finds no
effects of income in adolescence on children (Duncan & Brooks-Gunn, 1997), we suspect
that increases in family income might not benefit older children as much as younger
children, although it is unlikely that increases in income would play out negatively for
adolescents. Second, we suggest that maternal employment may have negative effects on
children in this age group, with three possible pathways suggested by the data: (1) maternal
employment may reduce parental supervision and, in turn, increase adolescent delinquency
among low-income families; (2) maternal employment may lead to greater household roles
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 233
and responsibilities when single parents go to work, and these responsibilities may
overburden adolescents in low-income families; and (3) maternal employment may encour-
age links with the work force that may introduce these children to adult modes of behaving.
Exploratory correlational analyses reveal that maternal employment is indeed positively
related to adolescent delinquency (controlling for income), while the frequency of conduct-
ing chores is negatively associated with delinquency. Also, adolescent employment is not
significantly associated with adolescent delinquency. These findings provide initial support
for the first explanation. However, much more work is needed before definitive causal
conclusions can be drawn.
4.4. Limitations
Several limitations of the current study bear mention. First, while the random assignment
design allows us to confidently attribute any significant effects to the SSP program, analysis
of the processes by which such effects are occurring is strictly nonexperimental. While
analyses of the effects of the SSP on potential mediators of the relation between the SSP and
measures of children’s well-being are suggestive, they cannot directly assess the extent to
which changes in these potential mediators caused the changes outcomes for children
observed. It is not clear, for example, whether income and employment had offsetting effects
for the youngest children or both had neutral effects; whether the benefits for the middle
childhood children are due to benefits of increases in employment or income or both; and
whether the negative effects for the oldest children were a result of increased employment and
reduced supervision or increased employment and increased household and employment
responsibilities of their own. This study is powerful in attributing any effects on children to
the SSP program and to the combined changes in employment, income, and other mediators
that resulted from the program, but any conclusions that try to tease out the precise nature of
those pathways are much more tenuous.
Second, while it was necessary to vary measures by age group to address differing
developmental constructs at varying ages, it limits our ability to directly compare effects from
one age group to another. Without a set of measures that address identical constructs across
age groups, it is impossible to know whether differing results are due to differences in the age
of the children examined or the differences in the measures collected.
Third, it is important to recall that the response rates were lowest, at 64%, for the oldest
group of children. While no evidence of response bias was found (see Morris & Michalo-
poulos, 2000 for more detail on these results), such low response rates do lend more caution
to the interpretation of the findings. It is not clear whether the same effects would have been
found if more children had participated in the study.
Finally, for all three age groups of children, any effects of the SSP on developmental
outcomes are small, and only on selected measures of children’s functioning. Assuming
children scored around the 25th percentile on average on a standardized test in the control
group (that is close to the level observed, for example, for the PPVT scores in this study), this
effect size change would move children to the 30th percentile, which is an increase of only 5
percentile points. While the employment and income impacts of the SSP are relatively large,
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239234
these did not translate into big changes in children’s home and child care environments, or in
children’s developmental outcomes. While it is important to find that welfare and employ-
ment programs can have an effect on children, it is also noteworthy that these programs are
not a panacea. From a policy perspective, we still have a long way to go to help low-income
children. From a research perspective, the small and limited impacts make further studies
critical in enabling researchers to draw more definitive conclusions about the effects of such
programs on children.
5. Conclusion
The well-being of children in low-income families has been relatively understudied in the
move to increase the self-sufficiency of low-income, single parents. The SSP is one of a small
set of random assignment studies recently conducted on the effects of welfare and
employment programs on children. Together with these other studies, the SSP can dramat-
ically increase our understanding about how programs that increase employment and income
among single mothers may affect children, pointing to the importance of recognizing the
moderating role of children’s developmental stage. Moreover, the findings underline the
importance of examining differences in impacts on children across differing developmental
periods, and including adolescents in studies of the effects of increases in employment and
income on children.
Acknowledgements
This paper summarizes an evaluation managed by the Social Research and Demonstration
Corporation (SRDC) and evaluated by SRDC in collaboration with the Manpower
Demonstration Research Corporation (MDRC). The study was funded and conceived by
Human Resources Development Canada (HRDC).
Special thanks to Jean-Pierre Voyer and Allen Zeesman of HRDC’s Applied Research
Branch and to John Greenwood and Saul Schwartz at SRDC. The authors also thank Richard
Veevers, Ann Brown, June Lavergne, Scott Meyer, Charlene Walker, and Joan Conway at
Statistics Canada; Mary Pichette at HRDC; Sharon Manson Singer at British Columbia’s
Ministry of Social Development and Economic Security; Karen Mann and Gary Baird at
Human Resources Development, New Brunswick; Melony McGuire and Trudy Megeny at
EDS Systemhouse, in Nova Scotia; Betty Tully and Elizabeth Dunn at Bernard C. Vinge and
Associates in British Columbia; Shelly Price and Linda Nelson at Family Services Saint John,
in New Brunswick; Martey Dodoo, Tracey Hoy, and Wanda Vargas at MDRC for their
assistance in data collection, management, and analysis. Thanks also to Gordon Berlin,
Robert Granger, Lisa Gennetian, and Judith Gueron at MDRC; Dan Offord, Michael Boyle,
and Ellen Lipman at McMaster University; Ariel Kalil at the University of Chicago; members
of MDRC’s Income Support Studies Committee and the comments of two anonymous
reviewers for their thoughtful comments.
P. Morris, C. Michalopoulos / Applied Developmental Psychology 24 (2003) 201–239 235
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