title: Reliability of instruments in a cooperative, multisite study: employment intervention demonstration program.
abstract: Reliability of well-known instruments was examined in 202 people with severe mental illness participating in a multisite vocational study. We examined interrater reliability of the Positive and Negative Syndrome Scale (PANSS) and the internal consistency and test-retest reliability of the PANSS, the Rosenberg Self-Esteem Scale, the Medical Outcomes Study Short Form-36 (SF-36), and the Quality of Life Interview. Most scales had good levels of reliability, with intraclass correlation coefficients (ICCs) and coefficient alphas above .70. However, the SF-36 scales were generally less stable over time, particularly Social Functioning (ICC = .55). Test-retest reliability was lower among less educated respondents and among ethnic minorities. We recommend close monitoring of psychometric issues in future multisite studies.
authors.affiliation: Department of Psychology, Indiana University Purdue University Indianapolis, 46202-3275, USA. mpsalyer@iupui.edu
authors.forename: M P
authors.initials: MP
authors.lastname: Salyers
authors.forename: G J
authors.initials: GJ
authors.lastname: McHugo
authors.forename: J A
authors.initials: JA
authors.lastname: Cook
authors.forename: L A
authors.initials: LA
authors.lastname: Razzano
authors.forename: R E
authors.initials: RE
authors.lastname: Drake
authors.forename: K T
authors.initials: KT
authors.lastname: Mueser
mesh_terms: D000328:Adult; D003299:Cooperative Behavior; D016832:Employment, Supported; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis* / Q000534:rehabilitation*; D011788:Quality of Life; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D016896:Treatment Outcome