title: Psychometric properties of questionnaires evaluating health-related quality of life and functional status in polytrauma patients with lower extremity injury.
abstract: BACKGROUND
  Long term disability is common among polytrauma patients. However, as yet little information exists on how to adequately measure functional status and health-related quality of life following polytrauma.
  
  
  OBJECTIVE
  To establish the unidimensionality, internal consistency and validity of two health-related quality of life measures and one functional status questionnaire among polytrauma patients.
  
  
  METHODS
  186 Patients with severe polytrauma including lower extremity injury completed the Sickness Impact Profile-136 (SIP-136), the Medical Outcomes Study 36-Item Short Health Survey (SF-36) and the Groningen Activity Restriction Scale (GARS) 15 months after injury. Unidimensionality and internal consistency was assessed by principal components analysis and Cronbach's alpha (alpha). To test the construct validity of the questionnaires, predetermined hypotheses were tested.
  
  
  RESULTS
  The unidimensionality and internal consistency of the GARS and the SF-36, but not the SIP-136 were supported. The construct validity of the SF-36, GARS and to a lesser extent the SIP-136 was confirmed.
  
  
  CONCLUSIONS
  The SF-36 and the GARS appear to be preferable for use in polytrauma patients over the SIP-136.
authors.affiliation: Department of Rehabilitation Medicine and EMGO Institute, VU University Medical Centre, Amsterdam, The Netherlands. martijn.steultjens@gcal.ac.uk.
authors.forename: Lian
authors.initials: L
authors.lastname: Jansen
authors.forename: Martijn Pm
authors.initials: MP
authors.lastname: Steultjens
authors.forename: Herman R
authors.initials: HR
authors.lastname: Holtslag
authors.forename: Gert
authors.initials: G
authors.lastname: Kwakkel
authors.forename: Joost
authors.initials: J
authors.lastname: Dekker