title: Range of motion measurements in hand surgery: should they be used for assessing outcomes?
abstract: OBJECTIVE
  The purpose of the study was to assess how context influences range of motion measurements in hand surgery.
  
  
  METHODS
  One hundred seventy-five consecutive patients presenting to a hand surgery clinic were evaluated over 7 sessions. Passive and active motion were measured with a goniometer and by visual estimation. The affected joint was measured by 3 different examiners-one hand surgeon and 2 research assistants (RAs). Measurements by the RAs were performed under the pretense of imaginary project titles and purposes.
  
  
  RESULTS
  Range of motion measurements were easily influenced. As the invented project's purpose became more specific and dependent on physician intervention, the bias became more pronounced. Measurements performed under construed project titles that promoted surgical intervention garnered outcomes that supported surgery (P < 0.01). Conversely, when the manufactured study's intent was to find support in conservative treatment, this outcome could also be generated (P < 0.01).
  
  
  CONCLUSIONS
  Range of motion measurements can easily be influenced by the context of the study, even in seemingly blinded examiners. Reliable range of motion measurements can only be made when the examiner has no knowledge of the study's intent.
authors: From the *Department of Orthopedic Surgery, David Geffen School of Medicine at UCLA; †Department of Orthopedic Surgery, University of California, Los Angeles; and ‡Department of Orthopedic Surgery, University of Southern California, Los Angeles, CA.
authors: Tristan Layton
authors: TL
authors: Hartzell
authors: Amit
authors: A
authors: Pandey
authors: Jonathan H
authors: JH
authors: Shahbazian
authors: Lily A
authors: LA
authors: Girson
authors: Nicholas M
authors: NM
authors: Bernthal
authors: Prosper
authors: P
authors: Benhaim
authors: Kodi K
authors: KK
authors: Azari
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D053587:Arthrometry, Articular / Q000379:methods / Q000523:psychology*; D015982:Bias; D005260:Female; D006225:Hand / Q000502:physiology / Q000601:surgery*; D050823:Hand Joints / Q000502:physiology* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D017063:Outcome Assessment, Health Care / Q000379:methods*; D011446:Prospective Studies; D016059:Range of Motion, Articular; D016037:Single-Blind Method