Validation of the German version of the Bodily Distress Syndrome 25 checklist in a representative German population sample

Objective: The Bodily Distress Syndrome 25 (BDS 25) checklist is a self-report instrument that can be used for case finding of a BDS in both clinical practice and research. We assessed the reliability and the internal and external validity of the German version of the BDS 25 in a sample of the general German population. Methods: The psychometric properties of the BDS 25 German were examined in a representative cross-sectional German population survey which included 2386 persons aged ≥14 years. Validation instruments included the Somatic Symptom Scale 8, the Giessen Subjective Complaints List 8 and the Patient Health Questionnaire 4. Participants were asked if they had been diagnosed with fibromyalgia or irritable bowel syndrome by a physician in the past. Results: The acceptance was high. Only 81 (2.3%) single items were not answered. Internal consistency was sufficiently high for all four subscales and the total score (α > 0.800). Exploratory and confirmatory factor analysis revealed clear evidence for a four-factorial structure with cardiopulmonary, gastrointestinal, musculoskeletal and general symptoms. Moderate to high correlations with other measures of somatic and psychological symptom burden were found. In latent class analysis, the model featuring three classes with no, moderate and severe BDS symptoms evinced the best model fit. Participants with self-reported fibromyalgia and irritable bowel syndrome were mainly found in the moderate and severe BDS group. Conclusions: The BDS 25 German has excellent psychometric properties to screen for BDS in the general population.