Chapter 11

Research Methods in Behavior Modification

Accuracy of Data: Sources of Inaccuracies

• some indirect assessments measure outcomes of behavior, not the target behavior itself

• rating scale questions and labels may not be clearly defined

• self-report data is flawed when memory is inaccurate

Accuracy of Data: Sources of Inaccuracies (continued)

• reactivity effects can modify normal responding• definition of the target behavior may be unclear• observers may not be trained or motivated to

record accurately• the detectability of the behavior may be impaired

Accuracy of Data: Increasing Reliability

• use more than one independent observer• check the interobserver reliability of observers• train and monitor observers

Accuracy of Data: Interobserver Reliability

• several methods are used to assess interobserver reliability– the session totals method compares the total

number of observations made by two observers– the interval-recording method compares the

number of intervals in which observers agree that behavior occurred

• reliability should be above 80%

Accuracy of Data: Training and Monitoring Observers

other procedures can enhance accuracy• let observers know their accuracy will be checked• use interobserver reliability procedures in training• use the procedures to evaluate the accuracy of

self-monitoring

Accuracy of Data: Training and Monitoring Observers (continued)

• use interobserver reliability procedures with indirect assessment

• interobserver reliability can be tested on samples of the observation period

Intrasubject Research

• the purpose of research will determine the appropriate research design

• intrasubject or single-subject designs are commonly used to evaluate treatment effects for an individual

• combinations of consecutive letters of the alphabet are used to label different designs

• each letter refers to a phase of treatment with A typically referring to baseline

AB Designs

• in AB designs, baseline (A) is followed by an intervention (B)

• comparisons (typically on a graph) can be made to see if changes occur from baseline to treatment conditions

• not an ideal method to isolate the cause of change

Reversal, ABA or ABAB Designs

• in reversal designs, baseline (A) is followed by treatment (B) and a return to the baseline (A) condition

• reinstatement of the baseline condition allows for a replication of the treatment effect

• replication makes it clearer that the treatment caused the change in behavior

Reversal, ABA or ABAB Designs (continued)

• reversal may not always be an appropriate design because:– withdrawal of treatment may not lead to a

return to baseline levels of behavior– withdrawal may be undesirable or unethical

Reversal Designs

Multiple-Baseline Designs

• multiple-baseline designs conduct more than one AB design concurrently with treatments beginning at different times

• multiple-baseline designs are useful when reversals cannot or should not be introduced

• multiple baselines can be across behaviors, baselining several similar behaviors within an individual

Multiple-Baseline Designs (continued)

• multiple baselines can be across subjects, applying the same treatment to the same behavior problems of two or more individuals

• multiple baselines can be across situations, baselining one type of behavior for a single individual in more than one setting

Multiple Baselines Across Behaviors

Changing-Criterion Designs

• changing-criterion designs change over time the criterion for success and look for a relationship between criteria changes and behavior change

• one might increase or decrease:– frequency requirements– rate requirements– duration requirements– other requirements

Alternating-Treatment Designs

• alternating-treatment designs compare the effects of two or more treatments applied at alternating times within the same time period

• does not require a reversal• several treatments can be evaluated at the same

time• a disadvantage is that the treatment effects can

interact

Alternating-Treatment Design

Group-Based Research

• group research designs compare average responses of large numbers of individuals subjected to different conditions

• offer more generalizable results• may not accurately reflect behavior of individuals

Group Designs: Within-Subjects Designs

• within-subject designs evaluate the influence of different conditions on the behavior of a single group of subjects

• methods follow the structure of intrasubject designs

• group average data are substituted for response measures of individuals

Group Designs: Between-Subjects Designs

• between-subject designs evaluate the influence of different conditions (independent variable) on the behavior (dependent variable) of different groups of subjects

• the simplest of designs compares behavior of a control group with that of an experimental group

Group Designs: Between-Subjects Designs (continued)

• the environment of the experimental group is manipulated and the environment of the control group is not

• the control serves as a reference for evaluating the influence of the manipulation

• experimental designs can include more than two groups

Group Designs: Between-Subjects Designs (continued)

• subjects are randomly assigned to groups• when therapies are evaluated, we sometimes use

waiting-list control groups

Group Designs: Quasi-Experimental Designs

• quasi-experimental designs are similar to experimental designs except subjects are not randomly assigned

• often used in applied settings where it may not be possible or ethical to randomly assign groups

Dimensions of Evaluation

effectiveness of treatments must be evaluated from several different perspectives:

• did behavior change generalize to the individual's natural environment?

• was the behavior change significant to the individual's functioning and change it enough to have a practical impact?

• do long-term savings and advantages warrant costs of the treatment?

Importance of the Change• was change clinically significant and socially valid?• did change have a meaningful impact on the

individual's life?• did treatment move the behavior within the normal

range?• is individual and those significant in his or her life

satisfied with the change?• are treatment techniques and procedures satisfactory

to all involved?

Measuring Clinical Significance and Social Validity

• impact can be evaluated by: – the individual– those involved with the individual – independent judges

• significance of change sometimes can be evaluated by measuring outcomes like arrests or other external interventions

Composing a Report

after intervention is complete, a report should describe:

• target behaviors• intervention techniques• treatment outcomes• follow-up results

Tips on Doing Behavior Modification Research

• demonstrate accuracy of observations by using more than one observer

• inform observers that you are using more than one observer

• train observers• behavior should be stable before changing

conditions• use a design other than a reversal design if you

cannot expect to recover baseline