The Attitude towards Polypills Questionnaire (APPQ): a phase I-III development and validation study in patients with cerebrovascular disease.

BACKGROUND AND PURPOSE The polypill approach has been proposed to reduce patients' pill burden, increase medication adherence and lower stroke incidence. However, little is known about patients' attitudes towards polypills for cerebrovascular medication. METHODS Based on the European Organization for Research and Treatment of Cancer Quality of Life Group questionnaire development guidelines, a questionnaire to measure patients' attitudes towards polypills for the secondary prevention of stroke (phase I-III) was developed. In phase I, issues were generated via literature review and interviews with patients and healthcare professionals. The issues were operationalized into items in phase II. In phase III the questionnaire was validated in a large single-centre sample, and test-retest and internal validity were evaluated. RESULTS In phase I, 34 relevant issues were identified through literature search and interviews. Pre-testing the questionnaire indicated high applicability and comprehensibility. The final Attitudes towards Polypills Questionnaire was tested in N = 260 patients and showed a two-factor structure. The factors were labelled 'concerns' and 'benefits'. The scales showed acceptable and good internal validity (concerns, Cronbach's α = 0.85; benefits, α = 0.93), but the scales' test-retest validity was ambiguous. On a 0 to 3 rating scale, concerns were rated lower than benefits (mean 1.07, SD 0.69 vs. mean 1.87, SD 0.89). CONCLUSIONS The Attitudes towards Polypills Questionnaire showed high comprehensibility and content validity to assess German language patients' attitudes towards a polypill medication. Our data and questionnaire may aid the implementation of polypill treatments in clinical practice and can be used in the design of future clinical trials on polypill therapy. Further validation of the questionnaire is advised.