Characteristics of non-responders to self-reported questionnaires in a large inflammatory bowel disease cohort study. (November 2015)

• Record Type: Journal Article
• Authors: Multone, Eléonore; Vader, John-Paul; Mottet, Christian; Schoepfer, Alain; Fournier, Nicolas; Burnand, Bernard; Michetti, Pierre; Pittet, Valérie
• Is Part Of: Scandinavian journal of gastroenterology. Volume 50:Number 11(2015)
• Page Start: 1348
• Page End: 1356
• Publication Date: 2015-11
• Subjects: Gastroenterology -- Periodicals; Digestive organs -- Diseases -- Periodicals; 616.33
• Languages: English
• ISSNs: 0036-5521

Abstract

<abstract> <title>Abstract</title> <p> <bold> <italic>Background.</italic> </bold> A major threat to the validity of longitudinal cohort studies is non-response to follow-up, which can lead to erroneous conclusions. The objective of this study was to evaluate the profile of non-responders to self-reported questionnaires in the Swiss inflammatory bowel disease (IBD) Cohort. <bold><italic>Methods.</italic></bold> We used data from adult patients enrolled between November 2006 and June 2011. Responders versus non-responders were compared according to socio-demographic, clinical and psychosocial characteristics. Odds ratio for non-response to initial patient questionnaire (IPQ) compared to 1-year follow-up questionnaire (FPQ) were calculated. <bold><italic>Results.</italic></bold> A total of 1943 patients received IPQ, in which 331 (17%) did not respond. Factors inversely associated with non-response to IPQ were age >50 and female gender (OR = 0.37; <italic>p</italic> < 0.001 respectively OR = 0.63; <italic>p</italic> = 0.003) among Crohn's disease (CD) patients, and disease duration >16 years (OR = 0.48; <italic>p</italic> = 0.025) among patients with ulcerative colitis (UC). FPQ was sent to 1586 patients who had completed the IPQ; 263 (17%) did not respond. Risk factors of non-response to FPQ were mild depression (OR = 2.17; <italic>p</italic> = 0.003) for CD, and mild anxiety (OR = 1.83; <italic>p</italic> = 0.024) for UC. Factors inversely associated with non-response to FPQ were: age >30 years, colonic only disease location, higher education and higher IBD-related quality of life for CD, and age >50 years or having a positive social support for UC. <bold><italic>Conclusions.</italic></bold> Characteristics of non-responders differed between UC and CD. The risk of non-response to repetitive solicitations (longitudinal versus transversal study) seemed to decrease with age. Assessing non-respondents' characteristics is important to document potential bias in longitudinal studies.</p> </abstract>