title: Clinical trial variability: quality control in a randomized clinical trial.
abstract: BACKGROUND
  A major issue in clinical trials in manual medicine is treatment variability. The challenge is to insure that the bounded treatment options are both representative of field practitioner behavior and consistent among research clinicians. This investigation assesses the treatment comparability of field practitioners and research clinicians, for a flexion-distraction treatment procedure, as quality control for a randomized clinical trial.
  
  
  METHODS
  Using a series of vignettes, we studied the level of agreement of treatment protocols between field clinicians, research clinicians and a reference clinician regarding treatment location, range of motion during treatment, and number of repetitions used within the flexion-distraction protocol.
  
  
  RESULTS
  Results indicated that reliability around decision making for anticipated location of spinal treatment was highest regardless of clinician group. For the research clinicians this level of agreement was ICC=0.88. Decision-making for treatment direction was second highest, at kappa=0.64 for the research clinicians. Reliability around the number of repetitions is poor ranging from ICC=0.18 to 0.34 depending on clinician type.
  
  
  CONCLUSIONS
  Understanding the disparity in treatment protocols is of value in the construction and maintenance of quality control in an actual randomized clinical trial setting. More work was recommended in the preparation of clinical trials and the understanding of clinical decision-making because these disparate factors may dramatically impact the generalizability of clinical trial results.
authors.affiliation: Canadian Memorial Chiropractic College, Toronto, Ontario, Canada. mmcgregor@cmcc.ca
authors.forename: Marion
authors.initials: M
authors.lastname: McGregor
authors.forename: Jerrilyn A
authors.initials: JA
authors.lastname: Cambron
authors.forename: James
authors.initials: J
authors.lastname: Jedlicka
authors.forename: M Ram
authors.initials: MR
authors.lastname: Gudavalli
mesh_terms: D002985:Clinical Protocols / Q000592:standards*; D003657:Decision Making; D006801:Humans; D020393:Manipulation, Spinal; D011786:Quality Control; D016032:Randomized Controlled Trials as Topic / Q000592:standards*