Validation and psychometric properties of the 8-item Morisky Medication Adherence Scale (MMAS-8) in Type 2 diabetes patients in sub-Saharan Africa

• Morisky Scale is proposed to be used to assess adherence in sub-Saharan Africa.
• Morisky scale has been used to assess adherence in other regions of the world especially where other resources are unavailable.
• Psychometric properties were assessed of this scale.
• Scale is an efficient way to measure medication adherence in Type 2 diabetic population in Togo.

ObjectivesResearch in the field of adherence to medications has not been explored in sub-Saharan Africa. The goal of this manuscript is to (1) validate the use of an adherence tool: a translated 8-item Morisky Medication Adherence Scale (MMAS-8) for Type 2 diabetes and (2) assess association between levels of adherence and psychometric properties.Methods154 Type 2 diabetic patients being chronically treated were surveyed from Togolese Diabetes Association using a demographic survey, 4-item Morisky Medication Adherence Scale (MMAS-4) and MMAS-8 from January to March 2012.ResultsInternal reliability for the 8-item scale showed the Cronbach alpha being 0.47. The MMAS-8 and MMAS-4 showed a Pearson's correlation of 0.6851. For known groups validity, the chi-square (χ2) tests of proportions showed a significant relationship between blood glucose control and MMAS-8 (χ2 = 12.17; p = 0.002). The sensitivity, specificity, positive predictive value and negative predictive value were 75%, 48.39%, 56.76%, and 68.18% respectively.ConclusionsPsychometric analyses showed that the MMAS-8 was a suitable way of measuring medication adherence in the study population given its low cost, ease of use, and the low income status of the country.