We have learned from the past that interventions targeting health behavior change involve assisting participants to identify and make changes in the habitual systems in their daily routines. Although the skills to change these habitual systems involve systems thinking (the ability to recognize patterns, interactions and interdependencies in a set of activities), no current measure exists to assess the extent to which systems thinking influences health behavior change. Our team is currently investigating the mediating role of systems thinking in enhancing healthy eating and exercise in overweight and obese adolescents. The purpose of this study was to develop and conduct psychometric testing of the Systems Thinking Scale for Adolescent Behavior Change (STS-AB).
In a first phase of this study, a panel of experts in systems thinking was used to develop an initial item set that was tested for understandability, content validity and stability in a small sample (N= 24) of adolescents enrolled in a weight management program. In a second phase, using a larger study of 359 urban adolescents enrolled in a weight management trail aged 10-13 (58% girls; 80% African American), factor analysis, reliability, and validity of the 16-item STS-AB were assessed.
Results of an exploratory factor analysis of the STS-AB indicated a 1-factor solution with good factor loadings, ranging from .40 to .67. The internal consistency reliability coefficient was .87. Test-retest reliability of the STS-AB was .48, p<.05. Systems thinking scores were higher in children who received systems thinking training compared to children not receiving training. Evidence of construct validity was supported by significant correlations with established measures of other variables commonly associated with health behavior change (motivation and self-efficacy for diet and physical activity). These findings indicate that the STS-AB is a valid and reliable measure of systems thinking for health behavior change in adolescents that can assist investigators to examine the extent to which systems thinking is a mechanism in health behavior change.