Using the Theory of Planned Behavior to examine effectiveness of an educational intervention on infant feeding in China

Objective: To determine the effectiveness of an educational intervention on infant feeding behaviors and mothers' psychosocial mediating variables based on the Theory of Planned Behavior (TPB), and to assess the predictive effect of mediating variables on mothers' intention and feeding practices. Methods: We did a cluster-randomized trial in 8 paired townships of Laishui County, China during 2006-2007. 599 mothers with infants aged 2-4-mo were enrolled at the baseline survey, of whom 485 were followed up after 11-mo intervention. Results: The intervention group had significantly higher scores than controls in knowledge, attitudes, self-efficacy, intention, norm beliefs, as well as feeding behaviors (Hotellings T-square = 143.96, P < 0.01). Mothers' intention towards recommended feeding behaviors was positively associated with mothers' attitudes, subjective norms and self-efficacy at baseline, and was associated with their attitudes, self-efficacy, and knowledge at post-intervention evaluation. Intervention, mothers' knowledge, intention and subjective norm of villagers were independent predictors of their feeding behaviors after intervention. Conclusions: Findings from this study suggested that TPB is an appropriate theory for explaining the effect of psychosocial factors such as knowledge, attitudes, self-efficacy, subjective norms, and intentions on infant feeding behaviors, and a useful guideline to design the targets and key approaches for infant feeding interventions.