title: Application of the OMERACT filter to measures of core outcome domains in recent clinical studies of acute gout.
abstract: OBJECTIVE
  To determine the extent to which instruments that measure core outcome domains in acute gout fulfill the Outcome Measures in Rheumatology (OMERACT) filter requirements of truth, discrimination, and feasibility.
  
  
  METHODS
  Patient-level data from 4 randomized controlled trials of agents designed to treat acute gout and 1 observational study of acute gout were analyzed. For each available measure, construct validity, test-retest reliability, within-group change using effect size, between-group change using the Kruskall-Wallis statistic, and repeated measures generalized estimating equations were assessed. Floor and ceiling effects were also assessed and minimal clinically important difference was estimated. These analyses were presented to participants at OMERACT 11 to help inform voting for possible endorsement.
  
  
  RESULTS
  There was evidence for construct validity and discriminative ability for 3 measures of pain [0 to 4 Likert, 0 to 10 numeric rating scale (NRS), 0 to 100 mm visual analog scale (VAS)]. Likewise, there appears to be sufficient evidence for a 4-point Likert scale to possess construct validity and discriminative ability for physician assessment of joint swelling and joint tenderness. There was some evidence for construct validity and within-group discriminative ability for the Health Assessment Questionnaire as a measure of activity limitations, but not for discrimination between groups allocated to different treatment.
  
  
  CONCLUSIONS
  There is sufficient evidence to support measures of pain (using Likert, NRS, or VAS), joint tenderness, and swelling (using Likert scale) as fulfilling the requirements of the OMERACT filter. Further research on a measure of activity limitations in acute gout clinical trials is required.
authors.affiliation: From the Department of Medicine, University of Otago, Wellington, New Zealand; Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama, USA; Department of Medicine, University of Auckland, Auckland, New Zealand; University of Pennsylvania and Veterans Affairs (VA) Medical Center, Philadelphia, Pennsylvania, USA; Department of Medicine, University of Florida, Gainesville, Florida, USA; SDG LLC, Cambridge, Massachusetts, USA; and Integrated Hospital Care Franchise, Immunology, Novartis Pharma AG, Basel, Switzerland; Pfizer Inc., New York, New York, USA; Epidemiology, Merck Sharp & Dohme Corp., Whitehouse Station, New Jersey, USA; Clinical Sciences, Regeneron Pharmaceuticals, Tarrytown, New Jersey, USA; Health & Rehabilitation Research Institute and School of Podiatry, Auckland University of Technology, Auckland, New Zealand; and Birmingham VA Medical Center and University of Alabama at Birmingham, Birmingham, Alabama, USA.
authors.forename: William J
authors.initials: WJ
authors.lastname: Taylor
authors.forename: David
authors.initials: D
authors.lastname: Redden
authors.forename: Nicola
authors.initials: N
authors.lastname: Dalbeth
authors.forename: H Ralph
authors.initials: HR
authors.lastname: Schumacher
authors.forename: N Lawrence
authors.initials: NL
authors.lastname: Edwards
authors.forename: Lee S
authors.initials: LS
authors.lastname: Simon
authors.forename: Markus R
authors.initials: MR
authors.lastname: John
authors.forename: Margaret N
authors.initials: MN
authors.lastname: Essex
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Watson
authors.forename: Robert
authors.initials: R
authors.lastname: Evans
authors.forename: Keith
authors.initials: K
authors.lastname: Rome
authors.forename: Jasvinder A
authors.initials: JA
authors.lastname: Singh
mesh_terms: D006073:Gout / Q000188:drug therapy* / Q000503:physiopathology; D006074:Gout Suppressants / Q000627:therapeutic use*; D006801:Humans; D017063:Outcome Assessment, Health Care; D010147:Pain Measurement; D011594:Psychometrics; D016032:Randomized Controlled Trials as Topic; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
chemical_list: D006074:Gout Suppressants
keywords: GOUT; OUTCOME MEASURES; PSYCHOMETRICS