title: [Are the responses of clients with psychiatric and addiction disorders using services for the homeless valid?].
abstract: OBJECTIVE
  To verify the validity of self-reported data on service use from clients with mental or substance abuse disorders in Montreal and Quebec services for homeless individuals.
  
  
  METHODS
  To compare the self-reported data from the Enquête chez les personnes itinérantes (Fournier, 2001) on health service use with official data from Quebec health services (MEDECHO and RAMQ).
  
  
  RESULTS
  The analysis shows a moderate-to-high level of concordance between the self-reported and the official data. Almost every item analyzed presents moderate but significant intraclass correlation coefficients for general and psychiatric hospitalization and use of psychiatric medication, but lower and nonsignificant coefficients for medical hospitalization. Participant characteristics such as mental disorders, homeless status, and substance abuse problems do not seem to have an impact on data validity.
  
  
  CONCLUSIONS
  The answers on health service use from individuals with mental health problems, homeless status, or substance abuse problems are generally valid in the results presented. Thus the self-reported data from these individiuals seems to be a generally valid source of data and an affordable one for research on service use or other domains.
authors.affiliation: Universit6 de Montr6al, Faculté des Sciences infirmi6res, Montréal, Québec. jean-pierre.bonin@umontreal.ca
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Bonin
authors.forename: Louise
authors.initials: L
authors.lastname: Fournier
authors.forename: Régis
authors.initials: R
authors.lastname: Blais
authors.forename: Michel
authors.initials: M
authors.lastname: Perreault
authors.forename: Noé Djawn
authors.initials: ND
authors.lastname: White
mesh_terms: D000328:Adult; D002170:Canada / Q000453:epidemiology; D005260:Female; D006703:Ill-Housed Persons; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology* / Q000628:therapy*; D008605:Mental Health Services / Q000706:statistics & numerical data*; D019966:Substance-Related Disorders / Q000453:epidemiology / Q000628:therapy; D011795:Surveys and Questionnaires