Cross-Cultural Validation of the Four-Dimensional Symptom Questionnaire (4DSQ) in Multimorbid Elderly People

Anna Exner, University of Siegen
Maria Kleinstäuber, Philipps-University of Marburg,
Wolfgang Maier, University Hospital Bonn
Angela Fuchs, Heinrich Heine-University Düsseldorf
Juliana J. Petersen, Goethe-University Frankfurt am Main
Ingmar Schäfer, University Medical Center Hamburg-Eppendorf
Jochen Gensichen, University Hospital of Ludwig-Maximilians-University Munich
Steffi G. Riedel-Heller, University of Leipzig
Siegfried Weyerer, Heidelberg University
Horst Bickel, Technical University of Munich
Hans-Helmut König, University Medical Center Hamburg-Eppendorf
Birgitt Wiese, Hannover Medical School
Gerhard Schön, University Medical Center Hamburg-Eppendorf
Martin Scherer, University Medical Center Hamburg-Eppendorf
Hendrik van den Bussche, University Medical Center Hamburg-Eppendorf
Berend Terluin, VU University Medical Center


Purpose: Psychosomatic symptoms and mental health problems are highly prevalent in multimorbid elderly people challenging general practitioners to differentiate between normal stress and psychopathological conditions. The 4DSQ is a Dutch questionnaire developed to detect anxiety, depression, somatization, and distress in primary care. This study aims to analyze measurement equivalence between a German version and the original Dutch instrument. Methods: A Dutch and a German sample of multimorbid elderly people, matched by gender and age, were analyzed. Equivalence of scale structures was assessed by confirmatory factor analysis (CFA). To evaluate measurement equivalence across languages, differential item functioning (DIF) was analyzed using Mantel–Haenszel method and hybrid ordinal logistic regression analysis. Differential test functioning (DTF) was assessed using Rasch analysis. Results: A total of 185 German and 185 Dutch participants completed the questionnaire. The CFA confirmed one-factor models for all scales of both 4DSQ versions. Nine items in three scales were flagged with DIF. The anxiety scale showed to be free of DIF. DTF analysis revealed negligible scale impact of DIF. Conclusions: The German 4DSQ demonstrated measurement equivalence to the original Dutch instrument. Hence, it can be considered a valid questionnaire for the screening for mental health problems in primary care.