Identifying Dimensions and Items for a Questionnaire to Assess Medication Adherence in Men and Women with Ischemic Heart Disease: Insights from the GENADHECAR Study

The objective of this study was to identify dimensions and items for a future questionnaire aimed at measuring medication nonadherence in people with ischemic heart disease, considering gender differences and incorporating the views of healthcare professionals, researchers, and patients. We conducted a mixed-method cross-sectional study at San Juan de Alicante University Hospital and Miguel Hernández University (Spain). The methods used to identify dimensions included a consensus group of healthcare and scientific professionals, an open-response survey for community pharmacists, a closed-response patient survey, and patient focus groups. When drafting the item list, we followed international recommendations related to the number and wording of items. Our study also included a qualitative review of the item list and response scales by psychologists. The resulting item list includes 41 potential items grouped into 26 dimensions and five domains: "patient", "treatment", "disease", "health professional-patient relationship" and "healthcare system". It covers aspects such as personal beliefs, mood, polypharmacy, disease symptoms, patient-healthcare professional interaction and healthcare system factors. Response options are presented on a 5-point Likert scale, including agreement-level responses and frequency-level responses. With the collaboration of patients, researchers, and healthcare providers, we potentially identified five domains, 26 dimensions, and 41 items with 5-point Likert scale response options. These will be considered in the subsequent development and validation of a questionnaire to measure medication adherence in patients with ischemic heart disease.