Investigating Fruit and Vegetable Consumption Using the Transtheoretical Model

• Published in: American journal of health promotion 2010-05, Vol.24 (5), p.324-333
• Main Authors: Horwath, Caroline C., Nigg, Claudio R., Motl, Rob W., Wong, Kristen T., Dishman, Rod K.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Choice Behavior; Cross-Sectional Studies; Feeding Behavior; Female; Food Preferences; Fruit; Hawaii; Hawaiian people; Health Behavior; Health technology assessment; Healthy food; Humans; Longitudinal Studies; Male; Measurement; Middle Aged; Models, Theoretical; Pacific Islander people; Randomized Controlled Trials as Topic; Self Efficacy; Selfefficacy; Transtheoretical model; Vegetables
• ISSN: 0890-1171; 2168-6602
• DOI: 10.4278/ajhp.071218138

Purpose. Test the applicability of the transtheoretical model (TTM) to adult fruit/vegetable consumption. Design. Cross-sectional random-digit dial survey. Setting. Hawaii. Subjects. 700 (62.6% female; age [mean ± SD], 47 ± 17.1 years; education [mean ± SD], 14.6 ± 2.8 years; 35.0% white, 31.1% Asian, 22.1% native Hawaiian/Pacific Islander, 11.8% other). Measures. Stages, processes, self-efficacy, decisional balance, and self-reported fruit/vegetable consumption. Analysis. Confirmatory factor analysis tested the factor structure. Analyses of variance were used to explore stage differences in constructs. Results. Stage distribution was precontemplation (33%), contemplation (4%), preparation (37%), action (3%), and maintenance (23%). A 10-factor process model with two higher-order correlated factors (experiential and behavioral) provided the best data fit (X2 = 1446.12; df = 366; p < .0001; comparative fit index [CFI] = .89; standardized root mean square residual [SRMR] = .05). The self-efficacy structure fit the data well (X2 = 81.86; df = 9; p < .0001; CFI = .94; SRMR = .04), as did the decisional balance structure (X2 = 37.42; df = 19;p = .007; CFI = .99; SRMR = .02). Processes, self-efficacy, decisional balance, and fruit/vegetable consumption behavior differed significantly by stage, with medium effect sizes for most variables. Conclusion. The variables revealed adequate fit to the theorized measurement models. TTM predictions regarding stage differences in self-efficacy, pros and cons, and fruit/vegetable consumption were confirmed; however, most experiential and behavioral processes increased in the early stages and then leveled off.