title: Single-subject research in rehabilitation: a review of studies using AB, withdrawal, multiple baseline, and alternating treatments designs.
abstract: OBJECTIVE
  To review the "methodologic rules" for using single-subject research designs (SSRDs) and to review the use of SSRDs in rehabilitation research of the past decade.
  
  
  METHODS
  CINAHL and MEDLINE searches using "single subject" and "single system" as key words for the period 1985-1995 yielded 61 articles related to rehabilitation.
  
  
  METHODS
  Studies were selected for review if they described one of four commonly used SSRDs, specifically AB, withdrawal, multiple baseline, or alternating treatments.
  
  
  METHODS
  Studies cited were identified by consensus and either exemplify adherence to the experimental rules of SSRDs or illustrate errors that result in threats to the validity of stated findings.
  
  
  RESULTS
  All four types of SSRDs have been reported in rehabilitation studies, sometimes incorrectly.
  
  
  CONCLUSIONS
  SSRDs, with their client-centered focus, are ideally suited for researching human behavior in the rehabilitation practice environment. Although numerous sources clearly identify the methodologic requirements for single-subject experiments, several studies violate the basic rules, threatening the validity of the results of these studies. Other properly applied SSRDs illustrate the strengths of this approach, which can produce empirical support for rehabilitation interventions.
authors.affiliation: School of Rehabilitation Sciences, University of British Columbia, Vancouver, Canada.
authors.forename: C L
authors.initials: CL
authors.lastname: Backman
authors.forename: S R
authors.initials: SR
authors.lastname: Harris
authors.forename: J A
authors.initials: JA
authors.lastname: Chisholm
authors.forename: A D
authors.initials: AD
authors.lastname: Monette
mesh_terms: D006801:Humans; D012046:Rehabilitation; D012107:Research Design