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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.