title: Examining factorial structure and measurement invariance of the Brief Symptom Inventory (BSI)-18 among drug users.
abstract: The purpose of this study is to examine the factorial structure of the Brief Symptom Inventory 18 (BSI-18) and test its measurement invariance among different drug using populations. A total sample of 710 drug users was recruited using respondent-drive sampling (RDS) from three states: Ohio (n=248), Arkansas (n=237), and Kentucky (n=225). The results of confirmatory factor analysis (CFA) show: 1) the BSI-18 has a three-factor structure (somatization, depression, and anxiety) with an underlying second-order factor (global severity index of distress); and 2) its factorial structure and metric (factor loadings) are invariant across populations under study. However, the scalars (intercepts) of the BSI-18 items are not invariant, and the means of the latent factors also varied across populations. Our findings provide evidence of a valid factorial structure of the BSI-18 that can be readily applied to studying drug using populations.
authors.affiliation: Children Research Institute, Center for Clinic and Community Research, Children's National Medical Center, The George Washington University School of Medicine, Washington, DC 20010, USA. jiwang@gwu.edu
authors.forename: Jichuan
authors.initials: J
authors.lastname: Wang
authors.forename: Brian C
authors.initials: BC
authors.lastname: Kelly
authors.forename: Brenda M
authors.initials: BM
authors.lastname: Booth
authors.forename: Russel S
authors.initials: RS
authors.lastname: Falck
authors.forename: Carl
authors.initials: C
authors.lastname: Leukefeld
authors.forename: Robert G
authors.initials: RG
authors.lastname: Carlson
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001007:Anxiety / Q000453:epidemiology; D001131:Arkansas / Q000453:epidemiology; D003866:Depressive Disorder / Q000453:epidemiology; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D007629:Kentucky / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009820:Ohio / Q000453:epidemiology; D012720:Severity of Illness Index; D013001:Somatoform Disorders / Q000453:epidemiology; D019966:Substance-Related Disorders / Q000523:psychology*; D011795:Surveys and Questionnaires; D055815:Young Adult