Effect of a theory-based educational intervention for enhancing nutrition and physical activity among Iranian women: a randomised control trial.

Objective: The relative contribution of health promotion models (HPM) to improve health-related behaviours in intervention programmes is still limited. Here, we tested whether Pender's HPM operationalised in the educational intervention was effective to modify nutrition and physical activity (PA) behaviours among Iranian women.

Design: A randomised controlled field trial evaluating the efficacy of an educational intervention based on Pender's HPM to improve PA and nutrition behaviours from August 2016 to October 2016. R version 3.0.2 and SPSS version 16 were used to conduct multiple statistical analyses.

Setting: Ten public healthcare centres in Bojnourd, Iran were randomly divided into intervention and control groups. The experimental group received the full intervention programme, which included nine 4-h training sessions and consulting support via phone contact and social media group. The control group did not receive any intervention.

Participants: Women aged 4-6 years (n 202) were randomised to intervention (n 102) and control conditions (n 100) and completed baseline and 3-month follow-up.

Results: In the experimental group, the intervention programme had a significant effect (P < 0·05) on all construct of Pender's HPM and behaviour outcome, and the estimates for prior behaviours, self-efficacy, interpersonal influences, feeling, perceived benefits and barriers, commitment and behaviour outcomes in the intervention group were 0·72 (95 % CI 0·31, 0·98), 0·54 (95 % CI 0·27, 0·71), 0·74 (95 % CI 0·27, 0·91), 0·52 (95 % CI 0·19, 0·75), 0·62 (95 % CI 0·22, 0·91), 0·63 (95 % CI 0·30, 0·86) and 0·56 (95 % CI 0·37, 0·85), respectively.

Conclusions: Educational intervention based on Pender's HPM was feasible and highly acceptable to modify PA and nutrition behaviours in the women population.