PURPOSE: To examine associations between decisional balance, self-efficacy, fruit intake, and stage of change transition from precontemplation and contemplation with cross-sectional and longitudinal methods. DESIGN: A longitudinal cohort study with the use of electronic questionnaires was conducted. Three measurements were analyzed cross-sectionally, and the two intervals between the measurements were analyzed longitudinally. SETTING: A random sample of 1500 individuals from an existing Dutch Internet panel resulted in a cohort of 735 individuals. Of the cohort, 648 (response rate 88%), 592 (response rate 81%), and 570 (response rate 78%) respondents completed questionnaires at the start of the present study (T1), 53 days after T1 (T2), and 106 days after T1 (T3), respectively. SUBJECTS: Mean age was 37.5 years, 51% were women, and 57% ate less than the recommended intake of 250 g of fruit per day. MEASURES: Questionnaires included items measuring stage of change, factors favoring (pros) or working against (cons) behavior change, and self-efficacy. A food frequency questionnaire was used to assess fruit intake. RESULTS: Logistic regression analyses showed that pros, fruit intake, and self-efficacy predicted forward stage transition from precontemplation. Self-efficacy predicted forward stage transition from contemplation. Cons did not predict stage transitions. Results from longitudinal analyses were similar to cross-sectional results, except for self-efficacy: no differences between early stages in self-efficacy were found, whereas self-efficacy predicted these early stage transitions. CONCLUSIONS: Within the limitations posed by the sampling frame, results provided support for the Transtheoretical Model, although determinants might not always be stage specific.
de Vet, E. W. M. L., de Nooijer, J. M., de Vries, N. K., & Brug, J. (2005). Determinants of forward stage transition from precontemplation and contemplation for fruit consumption. American Journal of Health Promotion, 19(4), 278-285. https://doi.org/10.4278/0890-1171-19.4.278