title: Nonrandomized studies of rehabilitation for traumatic brain injury: can they determine effectiveness?
abstract: OBJECTIVE
  To examine the feasibility of investigating rehabilitation effectiveness for traumatic brain injury (TBI) with a nonrandomized design.
  
  
  METHODS
  Observational cohort with confounder control by regression methodology.
  
  
  METHODS
  Level I trauma center.
  
  
  METHODS
  Consecutive series of 365 individuals with TBI discharged to inpatient rehabilitation or home (78% follow-up).
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  The Glasgow Outcome Scale (GOS), Sickness Impact Profile (SIP), Burden Inventory, and Perceived Quality of Life (PQOL). The predictors of interest: discharge to comprehensive inpatient rehabilitation or home and inpatient rehabilitation length of stay (LOS).
  
  
  RESULTS
  Discharge to rehabilitation was associated with poorer functioning on the GOS (P=.03) and SIP (P=.57), an increase on the Burden Inventory (P=.14), and improved PQOL (P=.20). Similar results were found for longer lengths of inpatient rehabilitation.
  
  
  CONCLUSIONS
  The results appear to be because of a confounding effect rather than rehabilitation. The study design could not control for confounding that resulted from unmeasured or difficult to measure aspects of the clinical decisions for discharge placement and rehabilitation LOS. Furthermore, typical severity indices were inadequate to control for injury severity and recovery. Matching designs that investigate TBI rehabilitation are also at risk for inadequate confounder control.
authors.affiliation: Department of Rehabilitation Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA. jmpowell@u.washington.edu
authors.forename: Janet M
authors.initials: JM
authors.lastname: Powell
authors.forename: Nancy R
authors.initials: NR
authors.lastname: Temkin
authors.forename: Joan E
authors.initials: JE
authors.lastname: Machamer
authors.forename: Sureyya S
authors.initials: SS
authors.lastname: Dikmen
mesh_terms: D000293:Adolescent; D000328:Adult; D016009:Chi-Square Distribution; D015986:Confounding Factors, Epidemiologic; D006259:Craniocerebral Trauma / Q000534:rehabilitation*; D005240:Feasibility Studies; D005260:Female; D015600:Glasgow Coma Scale; D006699:Home Care Services / Q000706:statistics & numerical data; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010351:Patient Discharge / Q000706:statistics & numerical data; D011788:Quality of Life; D012047:Rehabilitation Centers / Q000706:statistics & numerical data; D012107:Research Design; D012307:Risk Factors; D018434:Sickness Impact Profile; D018709:Statistics, Nonparametric; D014193:Trauma Centers; D016896:Treatment Outcome