Development and validation of the Adherence to Asthma Medication Questionnaire (AAMQ)

BACKGROUND: Adherence to medication is the cornerstone to achieve the best treatment outcome. Pharmacists are healthcare professionals found in a pivotal position to assess asthmatic patients’ adherence to medication. A brief, reliable, and valid measure of patients adherence to mediations is useful to enable the pharmacists to deliver that vital service. OBJECTIVE: To develop a reliable and valid adherence assessment tool for asthmatic patients. METHODS: The Adherence to Asthma Medication Questionnaire (AAMQ-13) was developed based on an extensive literature review, followed by applying the Delphi technique, and then it was pilot-tested by 55 patients. The final AAMQ-13 was completed by 213 patients. Psychometric evaluation was assessed including reliability, criterion validity, and construct validity. RESULTS: The AAMQ-13 is a feasible 13-item questionnaire, as it can be completed within an average of two minutes. It has high reliability (Cronbach’s alpha= 0.87). Criterion-concurrent validity was established by comparing the AAMQ-13 to the Test of the Adherence to Inhaler (TAI) and the pharmacy refill records. Criterion-convergent validity was established by comparing the AAMQ-13 to the Asthma Control Test (ACT) questionnaire and the Positive Health Behaviors Scale (PHBS). Construct validity was established through AAMQ-13 factor analysis which revealed two factors explaining 51.76% of the total variance. CONCLUSION: The AAMQ-13 is a reliable and valid questionnaire with several desirable characteristics as it has high reliability, good criterion validity, and strong construct validity. The AAMQ-13 is a suitable questionnaire that can identify non-adherent patients and reveal the reasons behind their non-adherence : Asthma; Adherence to medication; Compliance; Questionnaire; Self-report; Scale; Survey