Effect of a health belief model–based intervention on oral self-care and quality of life in adults with type 2 diabetes: a quasi-experimental study

Oral health status and diabetes type 2 control have a two-way relationship, and both of them effect on quality of life. This study aimed to investigate the effectiveness of oral health educational intervention on self-care behaviors, and quality of life of type 2 diabetic patients using the health belief model (HBM).In this quasi-experimental study, 120-diabetic patients, participated (60 in each intervention and control group) in Shiraz, Iran, between August 2024 and March 2025. Data were collected through HBM based researcher made questionnaire, Geriatric Oral Health Assessment Index, and clinical examination based on DMFT and CPITN indices, before and three months after the intervention. Four 60-minutes educational sessions were conducted for intervention group, using interactive educational methods. Data were analyzed by SPSS 27 at significance level of < 0.05, using independent sample t-test, paired sample t-test, and Cohen's d as effect size coefficient.The mean ages of the control and intervention groups were 53.75 ± 7.55 and 56.07 ± 7.17 years respectively. After the intervention, except for perceived barriers which decreased significantly (P < 0.001), and DMFT and CPITN which did not change, mean scores of all other study variables were increased significantly in intervention group (P < 0.001). The intervention had large effect sizes on perceived susceptibility, benefits and Quality of life, while effect sizes for knowledge, perceived severity and barriers and oral hygiene behaviors were at moderate level.The educational interventions based on the behavioral change models, especially HBM can be effective in improving the self-care behaviors and quality of life of of patients with diabetes.