title: An evaluation of the Brief Symptom Inventory-18 using item response theory: which items are most strongly related to psychological distress?
abstract: The psychometric structure of the Brief Symptom Inventory-18 (BSI-18; Derogatis, 2001) was investigated using Mokken scaling and parametric item response theory. Data of 487 outpatients, 266 students, and 207 prisoners were analyzed. Results of the Mokken analysis indicated that the BSI-18 formed a strong Mokken scale for outpatients and prisoners, indicating strong unidimensionality. For students, only the depression and anxiety items formed a medium Mokken scale. Parametric item response theory analyses showed that the best discriminating items came from the depression and anxiety subscales.
authors.affiliation: Department of Psychometrics and Statistics, University of Groningen, Groningen, the Netherlands. r.r.meijer@rug.nl
authors.forename: Rob R
authors.initials: RR
authors.lastname: Meijer
authors.forename: Rivka M
authors.initials: RM
authors.lastname: de Vries
authors.forename: Vincent
authors.initials: V
authors.lastname: van Bruggen
mesh_terms: D000328:Adult; D001008:Anxiety Disorders / Q000175:diagnosis / Q000523:psychology; D003866:Depressive Disorder / Q000175:diagnosis / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008960:Models, Psychological; D010045:Outpatients / Q000523:psychology; D011329:Prisoners / Q000523:psychology; D011569:Psychiatric Status Rating Scales / Q000592:standards*; D011594:Psychometrics; D013315:Stress, Psychological / Q000175:diagnosis / Q000523:psychology*; D013334:Students / Q000523:psychology; D011795:Surveys and Questionnaires; D055815:Young Adult