The effect of educational intervention based on the theory of planned behavior on promoting dairy consumption among high school students in Rudbar-e-Jonoob, Iran

Consumption of dairy products is not sufficient in adolescents which may lead to some chronic diseases in adulthood. The present study aimed to determine the effects of an educational intervention on dairy consumption by adolscents based on the theory of planned behavior (TPB).

This quasi-experimental study was performed on 179 female students of high schools in 2022. Participants were randomly assigned into two groups of intervention and control. Data were collected using a self-administered questionnaire consisted of 4 parts and 52 questions. These parts including demographic characteristics, knowledge, questions related to the TPB, and dairy consumption. Intervention was applied to the intervention group based on the TPB for one month. Seventeen types of interventions (10 educational and 7 health-promotion oriented).

Two months after the termination of the intervention, data were recollected from the groups and analyzed using descriptive statistics, paired and independent t-tests, Wilcoxon, Mann-Whitney U, Chi-square, Pearson correlation coefficient, and Linear regression by SPSS version 21.

The mean age of the intervention and control groups were 13.56 ± 0.97 and 14.31 ± 1.31 years, respectively. Twenty-four percent of the variance in predicting dairy consumption was attributed to knowledge and Constructs of the TPB. Perceived behavioral control (PBC) and behavioral intention were significant predictors of dairy consumption (p<0.0001).

After intervention, all TPB constructs differed significantly between the intervention and control groups (p<0.05); however, within-group analysis indicated that only Attitude (p=0.003) and dairy consumption (p=0.04) improved significantly in the intervention group after intervention.

Theory-based educational interventions improved attitudes and increased dairy consumption in the intervention group. Therefore, it is suggested that health educators use interventions based on this theory to increase dairy consumption.