Investigating Theory of Planned Behavior Constructs in Predicting Intention and Behavior to lose Weight in Adolescents with Overweight and Obesity

Introduction: Globally, the prevalence of overweight and obesity is really increasing alarmingly in all communities and age populations. The aim of the current study was to investigate theory of planned behavior (TPB) constructs in predicting intention and behavior to lose weight in adolescents with overweight and obesity. Methods: A total of 125 adolescents aged 13-18 years with overweight and obesity who referred to Pediatric Clinic of Isfahan Cardiovascular Research Institute were enrolled in this descriptive-analytical, cross-sectional study in 2016-2017. Data were collected by a questionnaire, developed by the researchers based on the TPB constructs, whose validity and reliability were confirmed. Data analysis was conducted by Pearson correlation coefficient and linear regression in SPSS. Result: The mean age of the participants was 15.20±1.53 years. There were positive and significant correlations between all TPB constructs and intention and behavior to lose weight in the adolescents. The TPB constructs predicted 38% of intention and 44% of behavior. Perceived behavioral control was the most important predictor variable followed by subjective norms and attitude. Conclusion: Promoting perceived behavioral control should be considered a priority of health promotion programs for adolescents' weight loss. Also, the TPB can be used as an appropriate framework to plan for educative interventions for such adolescents to lose weigh