The Norse Feedback in a population of patients undergoing bariatric surgery-Psychometric properties of a digital computer-adaptive questionnaire assessing mental health

The Norse Feedback (NF) is a questionnaire developed for patient-reported outcome monitoring with a clinical feedback system (PRO/CFS). As mental health is a concern after bariatric surgery, the use of the NF as part of PRO/CFS may be beneficial. The aim of this study is to test the reliability and validity of the NF in patients who have been accepted for or have undergone bariatric surgery. We performed separate robust confirmatory factor analyses (CFAs) to test the unidimensionality on 19 of the NF scales. We also performed correlation analyses on 19 of the NF scales with the Obesity-related Problems scale (OP). We included 213 patients. In the CFA analyses, three out of 12 scales with four or more items showed satisfactory psychometric properties in all goodness of fit indices (Suicidality, Need for Control and Self-Criticism). Four scales showed satisfactory psychometric properties in all indices but RMSEA (Somatic Anxiety, Substance Use, Social Safety and Cognitive Problems). Several of the scales demonstrated floor effects. In the correlation analyses, 18 of the 19 scales showed small-to-moderate correlation coefficients with the OP. Our demonstration of satisfactory psychometric properties on several important scales of the NF suggests that this tool may prove valuable in the routine follow-up of mental health in this population. However, further work is needed to innovate the NF for patients undergoing bariatric surgery. publishedVersion