Background & aim: Diabetes is one of the most common health problems in the world that can be controlled through educational programs. Therefore, this study was carried out to evaluate the effect of educational intervention based on extended theory of reasoned action on self-care behaviors in patients with type 2 diabetes.

Methods: In this quasi-experimental study, 90 patients with type 2 diabetes were assigned into experimental (45 people) and control (45 people) groups using stratified randomization method. Data collection tool was a questionnaire based on the extended theory of reasoned action and self-care behaviors. Data were collected before and 3 months after the intervention. Data analyses were performed by parametric statistical tests using SPSS-20.

Results: The results showed that mean scores of all structures of extended theory of reasoned action has increased significantly in the intervention group after educational intervention (p<0.05). However, changes were not significant in control group (p>0.05). Educational intervention had also significant effect on promotion of self-care behaviors in patients of the intervention group.

Conclusion: The findings of the current study showed that designing interventions based on extended theory of reasoned action can be an appropriate framework to improve self-care behaviors in patients with type 2 diabetes.