Psychometric Properties of Morisky Medication Adherence Scale (MMAS) in Known Diabetic and Hypertensive Patients in a Rural Population of Kolar District, Karnataka

The World Health Organization (WHO) defines adherence as ‘‘the extent to which a person's medication-taking behaviour, following a diet and/or executing lifestyle changes, corresponds with agreed recommendations from a healthcare provider’. Adherence is a multi-factorial phenomenon and although various methods are available for the assessment of medication adherence, there is still no gold standard for the measurement of medication adherence.

To examine the psychometric properties of eight-item Morisky Medication Adherence Scale (MMAS-8) among diabetics and hypertensives.

The study was conducted at villages in Lakkur PHC, Malur taluk, Kolar district. Patients aging 18 years and above with a confirmed diagnosis of hypertension and diabetes, using antihypertensive and antidiabetic medications for the last six months were enrolled in the study. The translated version of the 8-itemed MMAS was administered by face-to-face interview. Pill count was used as a gold standard for validation and verified using empty blister packs. The data was analyzed using standard statistical software.

The mean ± SD of MMAS scores were 4.23 ± 0.9. The instrument demonstrated good internal consistency (Cronbach's alpha =0.7). MMAS sensitivity and specificity, with positive and negative predictive values, were 80.2%, 88.5%, 83.6% and 85.9%, respectively.

Results from this validation study conclude that the MMAS is a reliable and valid measure of medication adherence.