Development of a medication adherence scale for familial Mediterranean fever (MASIF) in a cohort of Turkish children

Objective. To develop and assess the validity and reliability of an adherence scale concerning medical treatment in paediatric FMF patients. Methods. The Medication Adherence Scale in FMF Patients (MASIF) is a 18-item questionnaire that evaluates adherence to medication in four domains. Validation of the instrument was accomplished in paediatric FMF patients (aged 2-18 years) under medication at least for 6 months. The first step was to build up the scale through qualitative approach (with interviews using semi-structured questions). Validation analyses included assessment of feasibility, face and content validity; construct validity, internal consistency and test-retest reliability. Results. One hundred and fifty patients with FMF were enrolled in the study. The mean age of the patients was 11.11±4.02 years and 48.7% of them were male. The MASIF was found to be feasible and valid for both face and content. It correlated with the Morisky Medication Adherence Scale as a gold standard thereby demonstrating good construct validity (r=0.515, p < 0.001). Assessment of content validity identified four subscales. The internal consistency, Cronbach's alpha was 0.728. There was a positive and significant correlation between test and retest scores (r=0.843; p < 0.001). Also, a significant correlation between parents' and children's reports (r=0.781, p < 0.001). Conclusion. Based on these results, the use of this scale to assess and follow up the adherence to treatment in paediatric FMF patients under medical treatment is recommended.