Development of a Taiwan version of the eight-item morisky medication adherence scale and factors influencing patients' comprehension

Objective: In Taiwan, patients' low adherence to medication needs immediate attention and rectification. This study was intended to evaluate patients' capability in comprehending a Mandarin- and Taiwanese-language Taiwan version of the eight-item Morisky Medication Adherence Scale (MMAS-8), and to explore the possible factors influencing patients' ability to understand. Methods: Sixty-five participants, recruited from the neurology clinics of two Taipei Medical University-affiliated hospitals, received semi-structured, one-on-one, in-depth interviews (using the Taiwan version of the MMAS-8 combined with open questions to ask the patients what they had heard and what their opinion was on the Taiwan version of the MMAS-8). A cross-sectional survey method was used to analyze the data. The original Taiwan version of the MMAS-8 was then modified according to the patients' and experts' opinion and was validated by expert review. Results: Lower comprehension of the response choices was related significantly to (1) age over 65 years (p <0.05), (2) education lasting less than 12 years (p <0.05), and (3) complex comorbid conditions (p <0.05). Many patients were confused by the dichotomous response choices in Question 1 to 7 and the wordings of Questions 2 and 8 of the original version of the Taiwan MMAS-8. Therefore, these were modified into more specified sentences according to patients' and experts' suggested opinion. Conclusion: The modified Taiwan version of the eight-item MMAS was validated by experts. Future research is needed to validate its psychometric properties.