title: Osteoarthritis antirheumatic drug trials. III. Setting the delta for clinical trials--results of a consensus development (Delphi) exercise.
abstract: Defining the minimum clinically important difference or delta to be detected in a clinical trial depends on a number of factors including the research hypothesis, patient characteristics, the nature of the intervention and the trial design. In 2 studies, we have developed standardized procedures for conducting outcome measurement based on current Food and Drug Administration and European League Against Rheumatism guidelines for osteoarthritis clinical trials, and determined the standard deviation for these outcome measures. In the final component of this series of studies, we have used a Delphi technique to establish estimates for delta, and calculated the sample size requirements under 2 different conditions of Type I and Type II error probabilities.
authors.affiliation: Division of Rheumatology, University of Western Ontario, London, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Bellamy
authors.forename: S
authors.initials: S
authors.lastname: Carette
authors.forename: P M
authors.initials: PM
authors.lastname: Ford
authors.forename: W F
authors.initials: WF
authors.lastname: Kean
authors.forename: N G
authors.initials: NG
authors.lastname: le Riche
authors.forename: A
authors.initials: A
authors.lastname: Lussier
authors.forename: G A
authors.initials: GA
authors.lastname: Wells
authors.forename: J
authors.initials: J
authors.lastname: Campbell
mesh_terms: D002986:Clinical Trials as Topic / Q000379:methods*; D003697:Delphi Technique; D006801:Humans; D010003:Osteoarthritis / Q000188:drug therapy*