Patient Preference and Adherence (Jan 2019)
Comparison of anonymous versus nonanonymous responses to a medication adherence questionnaire in patients with Parkinson’s disease
Abstract
Tino Prell,1,2 Denise Schaller,1 Caroline Perner,1,3 Gabriele Helga Franke,4 Otto W Witte,1,2 Albrecht Kunze,1 Julian Grosskreutz1,2 1Department of Neurology, Jena University Hospital, Jena, Germany; 2Center for Healthy Aging, Jena University Hospital, Jena, Germany; 3Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA; 4University of Applied Sciences, Psychology of Rehabilitation, Stendal, Germany Purpose: Adherence to medication can be assessed by various self-report questionnaires. One could hypothesize that survey respondents tend to answer questions in a manner that will be viewed favorably by others. We aimed to answer if anonymous and nonanonymous responses to a questionnaire on medication adherence differ.Patients and methods: Adherence was assessed with the German Stendal Adherence with Medication Score (SAMS), which includes 18 questions with responses based on a 5-point Likert scale. Anonymous data from 40 subjects were collected during a symposium for patients with Parkinson’s disease (PD), and nonanonymous data were obtained from 40 outpatient-clinic PD patients at the Department of Neurology.Results: The two groups (anonymous self-reported questionnaire and nonanonymous) did not differ in terms of demographical characteristics and the SAMS sum score. However, anonymously collected data showed significant higher scoring for the item 6 (“Do you forget your medications?”) than the data collected nonanonymously (P=0.017). All other items of the SAMS did not significantly differ between both groups.Conclusion: Overall assessment of adherence does not depend on whether the patient remains anonymous or not. There seems to be no relevant social desirability bias in nonanonymous responses. Keywords: self-report, adherence questionnaire, Parkinson’s disease, anonymous, nonadherence