TOWARD A MORE VALID AND RELIABLE HEALTH LOCUS OF CONTROL SCALE

DOUGLAS COOPER A N D MARYANN FRABONI North Bay Psychiatric Hospital

North Bay, Ontario, Canada

The Multidimensional Health Locus of Control Scale was administered in conjunction with a back care program offered to staff at a psychiatric hospital (N 82). Validity and reliability of the alternate forms were examined, as was the addition of Forms A and B. The factor structure failed to replicate the original multidimensional construct; hence, suggestions are made to return to the earlier internal/external model and to add the alternate forms to increase reliability.

Of the many instruments inspired by Rotter’s (1966) I-E Scale, the Health Locus of Control Scale (HLC; Wallston, Wallston, Kaplan, & Maides, 1976) measures peo- ple’s belief in the external and internal controlling agents of their physical health. From this unidimensional scale, the Multidimensional Health Locus of Control (MHLC) evolved (Wallston, Wallston, & De Vellis, 1978). The multidimensional approach derived from Levenson’s (1978) study of a non-health-specific measure of locus of control. The 18-item parallel A and B forms of the MHLC use dpoint Likert items and yield three scores: Internal (I), powerful others (P), and chance (C), which Wallston et al. (1978) deem to be more valid and powerful measures of their multifaceted construct. These scale scores indicate the degree to which the individual believes that his or her health is controlled by self, “powerful others” (such as a doctor), or by fate and luck.

The MHLC originally was validated on a sample obtained in a metropolitan air- port (Wallston et al., 1978). Since then, contradictory evidence has accumulated on the validity and internal consistency of the subscales. In research that employed samples of medical and dental students (Winefield, 1982), college students (O’Looney & Bar- rett, 1983), cigarette smokers (Coelho, 1985), alcoholics (Russell & Ludenia, 1983), and rehabilitation patients (Umlauf & Frank, 1986), subscale intercorrelations and factor analyses did not support a clear distinction between Scales P and C. Internal consisten- cy reliability, measured by Cronbach’s alpha coefficient, has been reported to be as low as .49 for Scale C and .58 for P (Winefield, 1982). Scale I consistently has been demonstrated to be stable and homogeneous. In this evaluation, measures of reliability and validity were applied to both Forms A and B, as well as to the addition of scores on A and B (T-MHLC). The possibility of nonorthogonal relationship between items, as questioned by Umlauf and Frank (1986), also was examined.

METHOD Subjects and Procedure

Both MHLC forms were included in a booklet of measures given to staff of a psychiatric hospital at the commencement of a 7-hour back care education program. The workshop was offered once a month to small groups (8-20), irrespective of the presence or absence of back injury. Of the 82 persons in the sample (29 male, 53 female),

We gratefully acknowledge the assistance of Dr. Matti I. Saari of Nipissing University College for com-

Requests for reprints should be addressed to Maryann Fraboni, Psychology Department, North Bay ments on the final draft of this article and of Lynn Moore, who typed the manuscript.

Psychiatric Hospital, Box 3010, North Bay, Ontario, PlB, 8L1, Canada.

536

Multidimensional Health Locus of Control Scale 537

31 reported having had no back injury, 19 reported one, and 32 reported two or more. Ages were in a 19- to 62-year range, mean = 35.6.

The sample comprised four socioeconomic levels: Unskilled clerical, sales, service, manual labor (N = 10); skilled clerical, sales, service, crafts, trades (N = 12); semi- professionals (N = 46); professionals and high-level management (N = 14). (SES was coded using Pineo-Porter classification system [Pineo, Porter, & McRoberts, 19771).

RESULTS Table 1 presents a summary of the MHLC scores obtained on Forms A and B.

Maximum scale scores are 36; higher scores indicate higher agreement with belief in that particular locus of control. Statistics for T-MHLC were computed on the mean of Forms A and B scores. The descriptive analyses reveal an overall trend in the sample toward an internal locus of control, with higher means and range values consistently across forms.

Table 1 Summary of Descriptive Statistics and Alpha Coefficients for MHLC Scale

Internal Chance Powerful Others

Form A Range 12-35 6-28 6-25

M 26.51 15.60 16.31

SD 4.97 5.20 4.84

Alpha . a7 .76 .68

Form B Range 13-34 6-28 6-30

M 26.31 16.50 16.94

SD 4.79 5.31 5.14

Alpha .86 .15 .77

T-MHLC Range M SD

Alpha

15.5-34 6-27 6.5-26.5

26.48 15.99 16.59

4.55 4.84 4.44

.88 .78 .77

No significant differences were found on the MHLC subscales for groups based on sex, age, socioeconomic status, and number of back injuries. Neither were these variables useful predictors of the scales. When used in a stepwise multiple regression analysis, the Rs were small (.17 at the highest for SES) and represented, at the most, 3% of the variance for socioeconomic status when Scale I was the dependent variable. Age showed the least relationship with all the scales.

Various factor analyses were computed with MHLC item scores to evaluate the construct validity of the subscales. Factor loadings (> .3) were compared to scale items designated by Wallston et al. Initial difficulty in finding the anticipated item loadings

538 Journal of Clinical Psychology, July 1988, Vol. 44, No. 4

when a Varimax rotation was applied led to the exploration of item relationships through equamax, quartimax, and oblique rotations. Results when the criteria for factor extrac- tion were set to three, four, and five also were examined with each rotation in hope of a closer representation of the scales. The various extraction and rotation methods, including oblique, failed to replicate results used to support the constucts of the three subscales. For the separate analyses of A and B, loadings from principal components analysis, and Kaiser’s Varimax rotation are the best approximation of the Wallston et al. constructs that can be gleaned from this sample of subjects. In both Forms A and B, the items designated for Scale I load on Factor 1. Factor 2 consists mainly of Scale P items. Scale C items, however, do not vary together well and are distributed across the remaining factors or interspersed with loadings on Factor 1. The difference in the number of factors extracted (A, 5 ; B, 3) makes questionable the consistency of the con- struct validity across forms.

The results of both Varimax and oblique rotations applied to T-MHLC reaffirmed the results found in the analyses of separate forms. Though the obliquely rotated loadings were no more representative of the constructs than the orthogonally rotated ones, the coefficients were at least higher.

Table 2 Factor Loadings of T-MHLC- Oblique Rotationa

Item Factor 1 Factor 2 Factor 3 Factor 4

TI (1) - .272 .781 .085 - .297

T2 (C) .450 - .159 - .512 - .042

T3 (PI - .184 .161 - .881 - .005

T5 (PI - .023 .038 - .826 -.1m

T6 (1) - .036 .844 - .092 .lo4 l-7 (P) .717 - .026 - .028 - .028

T4 (C) .374 .210 - .I84 - .348

T8 (1) .467 .563 .281 .154 T9 (C) 556 - .037 - .011 - .363 TI0 (P) - .I55 .007 - .329 - .603

T12 (I) - .055 .899 - . I 6 0 - .006

TI3 (I) .140 .832 .048 .029 T14 (P! .217 - .003 .7% .046 TI5 (C) .439 - .278 - .256 - .354

T16 (C) .I89 - .059 .lo3 - .706

T17 (1) .026 .838 - . I35 .093

TI1 (C) .016 - .019 .074 - .850

T18 (P) .020 .003 - .654 - .217

*Eigenvalue = 1 .

Regardless of the Forms (A, B, T-MHLC), rotation used, or the manipulation of extracting factors, most items loaded heavily on the one or two factors, with sporadic loadings across the rest.

The subscales of Form A, B and T-MHLC were examined for internal consistency by use of Cronbach’s Alpha coefficient (Table 1). Scale I is the most homogeneous scale.

Multidimensional Health Locus of Control Scale 539

Scale C and P are also fairly stable although the internal consistency of P differs by .09 between forms, whereas the other scales are remarkably consistent across forms. This difference may be due to the inadequacy of one of the parallel items. Adding forms A and B (T) greatly improves the alpha of Scale P.

Computation of the Alpha if each item were deleted singularly showed that items on Scales I and C had alphas in a close range about the total scale's alpha. Scale P's coefficients are lower; they dip to .56 for item 14 and jumped to a range of .70-.78, while the other two scales were nearly identical across forms. Use of T-MHLC, as with the total scale alpha, strengthened the stability of P without changing the order of the contribution of items.

Pearson intercorrelations between alternate forms were fairly high (Table 3); however, Scales C and P seemed less distinctive than Scale I. Scale BC has very diffuse effects over all I Scales, while Scales AP and BP are the most unique. The correlation between AP and BP is only .63, although corresponding items were designed to be similar.

Table 3 Intercorrelations of A, B and T-MHLC Subscales

A1 BI TI AC BC TC AP BP TP

A1 1 .OO .80 .95

- .33 - .56 - .48 -.19 - .27

- .25

B1 TI AC BC TC AP BP TP

1 .00 .94 1.00

- .38 -.37 1.00 - .54 - .58 .I1 1.00 - .50 -.52 .92 .92 1.00 - .24 -.22 .40 .33 .40 1.00 - .25 -.27 .30 .40 .38 .63 1.00 - .27 - .21 .38 .41 .43 .!XI .91 1.00

DISCUSSION AND CONCLUSION The factor analyses failed to confirm the construct validity of the MHLC Scales.

Item loadings do not replicate sharp enough differences between the constellation of items that Wallston et al. have used for the subscales, even when Forms A and B are added and rotated nonorthogonally. The lack of distinctiveness of P and C Scales, evidenced by the factor analytic and subscale intercorrelation results, questions the multidimensionality of the construct. Combining P and C to return to an external/in- ternal scale would strengthen the validity of this health-specific measure, and adding Forms A and B to increase the internal consistency could solve the reliability deficits of the earlier Health Locus of Control Scale.

In summary, the psychometric properties reported here, coupled with the findings of other authors, indicate the need for caution in the use and interpretation of the MHLC.

Choosing the multidimensional concept over a simpler dichotomous one does not seem justifiable, particularly when applied to more homogeneous populations.

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cigarette smokers. Journal of Clinical Psychology, 41, 372-316.

540 Journal of Clinical Psychology, July 1988, Vol. 44, No. 4

LEVENSON, H. (1973). Multidimensional locus of control in psychiatric patients. Journal of Consulting and Clinical Psychology, 41, 397-404.

O'LOONEY, B., L BARREIT, P. (1983). A psychometric investigation of the Multidimensional Health Locus of Control questionnaire. Journal of Clinical Psychology, 22, 217-218.

PINEO, P., PORTER, D., L MCROBERTS, H. (1977). The 1971 Census and the socioeconomic classification of occupations. Canadian Journal of Sociology and Anthropology, 14, 19-102.

ROTTER, J. (1966). Generalized expectancies for internal versus external control of reinforcement. Psychology Monograph, 80, 609.

RUSSELL, S. , & LUDENIA, K. (1983). The psychometric properties of the Multidimensional Health Locus of Control Scale in an alcoholic population. Journal of Clinical Psychology, 39, 453-459.

UMLAUP, R., & FRANK, R. (1986). Multidimensional health and locus of control in a rehabilitation setting. Journal of Clinical Psychology, 42, 126-128.

WALLSTON, B., WALLSTON, K., & DEVELLIS, R. (1978). Development of the Multidimensional Health Locus of Control (MHLC) Scale. Health Education Monograph, 6 , 161-170.

WALLSTON, B., WALLSTON, K., KAPLAN, G., & MAIDES, S. (1976). Development and validation of the Health Locus of Control (HLC) Scale. Journal of Consulting and Clinical Psychology, 44, 580-585.

WINEFIELD, H. (1982). Reliability and validity of the Health Locus of Control Scale. Journalof Personulity Assessment, 46, 614-619.

COGNITIVE DYSFUNCTION AND CHANGE IN MULTIPLE SCLEROSIS

FREDRICA R. HALLIGAN Fordham University

HERMAN P. FRIEDMAN Systems Research Institute

International Business Machines

MARVIN REZNIKOFF Fordham University

NICHOLAS 0. LA ROCCA Albert Einstein College of

Medicine of Yeshiva University

A cross-sectional study of 60 multiple sclerosis outpatients assessed neuro- psychological variables in relation to age, duration of disease, and degree of disability. The test battery included subtests of the WAIS (Vocabulary, Similarities, and Digit Span); the Raven matrices; and memory tests (Wechsler Paired Associates, Benton Visual Retention). Results showed that cognitive functioning of MS patients varies considerably. There is a general mild decline that affects abstract reasoning and memory as the disease pro- gresses. These deficits are usually not sufficient to impair occupational or social functioning. In addition, there is spotty deterioration in certain cognitive functions for some patients (17%). Only a small subsample (6.7Vo), however, showed global deterioration significant enough to be highlighted by an Index of Dementia that was developed for this investigation.

Multiple sclerosis (MS) is a demyelinating disease in which the protective coating of the neurons in the central nervous system is destroyed selectively. The lesions, known as sclerotic plaques, may occur in the brain, optic nerves, or spinal chord; the most

The present research was supported in part by a grant to Fredrica R. Halligan from the Schering-Plough Fellowship Fund and in part by the National Institute on Disability and Rehabilitation Research Grants GOO 800 6808 and GOO 8300040 to the Medical Rehabilitation Research and Training Center for Multiple Sclerosis, Albert Einstein College of Medicine.

Correspondence and requests for reprints should be addressed to Fredrica R. Halligan, Ph.D., Counsel- ing Center, Fordham University, Bronx, New York 10458-5157.