title: Reliability and validity of a modified Colorado Symptom Index in a national homeless sample.
abstract: This study examined the reliability and construct validity of a modified version of the Colorado Symptom Index (MCSI), a brief, self-report measure of psychological symptomatology, in a study of interventions to prevent homelessness. Eight projects in a national, cooperative study collected new data at baseline, 6, and 12 months using a set of common measures as well as site-specific instruments. The pooled sample consisted of 1,381 persons in treatment for mental illness or substance abuse (or both), of which 84% had a history of homelessness. The analyses employed classical and Rasch methods to examine the MCSI's content validity, internal consistency and item quality, test/retest reliability, dimensionality, appropriateness for the sample, construct validity, and responsiveness to change. This 14-item scale was found to be a reliable and valid measure of psychological symptoms in this sample. Its content was consistent with other symptom measures, its high internal consistency and test-retest coefficients supported its reliability, its relationships to other measures indicated that it had good construct validity, and it was responsive to change. We conclude that the MC
authors.affiliation: Department of Veterans Affairs, Hines VA Hospital, IL, USA. kjconrad@uic.edu
authors.forename: K J
authors.initials: KJ
authors.lastname: Conrad
authors.forename: J R
authors.initials: JR
authors.lastname: Yagelka
authors.forename: M D
authors.initials: MD
authors.lastname: Matters
authors.forename: A R
authors.initials: AR
authors.lastname: Rich
authors.forename: V
authors.initials: V
authors.lastname: Williams
authors.forename: M
authors.initials: M
authors.lastname: Buchanan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006703:Ill-Housed Persons / Q000523:psychology* / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D008875:Middle Aged; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires