Psychometric Properties of the Iranian Version of the Diabetes Numeracy Test-15

BACKGROUND: Low health literacy (HL) of patients has obtained more attention as a risk factor for poor adherence to treatment and adverse outcomes in chronic disease's management particular in diabetes care. Diabetes Numeracy Test-15 (DNT-15) has been developed specifically for this purpose. The objective of the current study is to evaluate psychometric properties of Iranian (Persian) version of the DNT-15. METHODS: The shortened version of the DNT (15-items) was completed by 120 patients with diabetes. The Kuder–Richardson Formula 20 for internal consistency was conducted. Content validity, criterion-related validity, and construct validity were also evaluated. RESULTS: The average score on the DNT was 72% and took an average of 25 minutes to complete. The DNT-15 had a very good internal reliability (KR-20 = 0.90) and also content validity (content validity ratio: 089 and content validity index: 0.86). CONCLUSIONS: The DNT-15 (Persian version) is a reliable and valid measure of diabetes-related numeracy skills for Iranian patients with diabetes; however, additional studies are needed to further explore the association between diabetes-specific numeracy and acculturation and their impact on diabetes-related outcomes in Iranian population.