The Persian version of the 8-item Morisky Medication Adherence Scale (MMAS-8): can we trust it?

Diabetes mellitus (DM) is a common serious health problem. Medication adherence is a crucial determinant of therapeutic success in patients with diabetes mellitus. This study aims to examine the 8-item Morisky Medication Adherence Scale (MMAS-8) psychometric properties among diabetic patients. This study was carried out at the Internal Medicine clinic of Firooz Abadi Hospital in Tehran, Iran, from 2018 to 2020. The English version of the MMAS-8 was translated into Persian and administered to patients with diabetes mellitus. A total of 150 patients who had diabetes were included. Cronbach's alpha was calculated to assess the reliability. According to the recommended scoring method, the Mean ± SD of MMAS-8 scores was 4.97 ± 1.92. Good internal consistency was found in our study (Cronbach's α = 0.70). Not any significant relationship between MMAS-8 categories and occurrence of complications was found. The findings of this validation study indicate that the Persian version of the MMAS-8 is a reliable measure of medication adherence, but it has not acceptable validity. Further studies are needed to reach a good validity.