title: PEDro or Cochrane to Assess the Quality of Clinical Trials? A Meta-Epidemiological Study.
abstract: OBJECTIVE
  There is debate on how the methodological quality of clinical trials should be assessed. We compared trials of physical therapy (PT) judged to be of adequate quality based on summary scores from the Physiotherapy Evidence Database (PEDro) scale with trials judged to be of adequate quality by Cochrane Risk of Bias criteria.
  
  
  METHODS
  Meta-epidemiological study within Cochrane Database of Systematic Reviews.
  
  
  METHODS
  Meta-analyses of PT trials were identified in the Cochrane Database of Systematic Reviews. For each trial PeDro and Cochrane assessments were extracted from the PeDro and Cochrane databases. Adequate quality was defined as adequate generation of random sequence, concealment of allocation, and blinding of outcome assessors (Cochrane criteria) or as trials with a PEDro summary score ≥5 or ≥6 points. We combined trials of adequate quality using random-effects meta-analysis.
  
  
  RESULTS
  Forty-one Cochrane reviews and 353 PT trials were included. All meta-analyses included trials with PEDro scores ≥5, 37 (90.2%) included trials with PEDro scores ≥6 and only 22 (53.7%) meta-analyses included trials of adequate quality according to the Cochrane criteria. Agreement between PeDro and Cochrane was poor for PeDro scores of ≥5 points (kappa = 0.12; 95% CI 0.07 to 0.16) and slight for ≥6 points (kappa 0.24; 95% CI 0.16-0.32). When combining effect sizes of trials deemed to be of adequate quality according to PEDro or Cochrane criteria, we found that a substantial difference in the combined effect size (≥0.15) was evident in 9 (22%) out of the 41 meta-analyses for PEDro cutoff ≥5 and 10 (24%) for cutoff ≥6.
  
  
  CONCLUSIONS
  The PeDro and Cochrane approaches lead to different sets of trials of adequate quality, and different combined treatment estimates from meta-analyses of these trials. A consistent approach to assessing RoB in trials of physical therapy should be adopted.
authors.affiliation: CLEAR (Connecting Leadership, Education, and Research) Outcomes Research Program, University of Alberta, Faculty of Nursing, University of Alberta, Edmonton, Canada; Rehabilitation Research Center, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Canada.
authors.forename: Susan
authors.initials: S
authors.lastname: Armijo-Olivo
authors.affiliation: Universitat Bern, Institute of Primary Health Care, Gesellschaftstrasse 49, Bern, 3013, Switzerland.
authors.forename: Bruno R
authors.initials: BR
authors.lastname: da Costa
authors.affiliation: CLEAR (Connecting Leadership, Education, and Research) Outcomes Research Program, University of Alberta, Faculty of Nursing, University of Alberta, Edmonton, Canada.
authors.forename: Greta G
authors.initials: GG
authors.lastname: Cummings
authors.affiliation: Rehabilitation Research Center, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Canada.
authors.forename: Christine
authors.initials: C
authors.lastname: Ha
authors.affiliation: Rehabilitation Research Center, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Canada; Catholic University of Maule, Department of Physical Therapy, Talca, Chile.
authors.forename: Jorge
authors.initials: J
authors.lastname: Fuentes
authors.affiliation: Orthodontic Graduate Program, School of Dentistry, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Humam
authors.initials: H
authors.lastname: Saltaji
authors.affiliation: Institute of Social & Preventive Medicine (ISPM), University of Bern, Bern, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Egger
mesh_terms: D002986:Clinical Trials as Topic; D016021:Epidemiologic Studies; D006801:Humans; D018401:Sample Size