Phase one: Questionnaire development
A structured questionnaire with predefined domains of interest was constructed based on an extensive review of the items included previously in published adherence questionnaires (21). The most commonly used items published in adherence questionnaires were included in the first draft of the (AAMQ). Other items that seem important to assess adherence were added after being agreed upon by the research team. The finalized items for the first draft (AAMQ-V1) were reviewed by the research team in order to combine concepts and to remove duplicates or irrelevant items (22).