title: Survey Definitions of Gout for Epidemiologic Studies: Comparison With Crystal Identification as the Gold Standard.
abstract: To identify the best-performing survey definition of gout from items commonly available in epidemiologic studies.
  
  
  
  Survey definitions of gout were identified from 34 epidemiologic studies contributing to the Global Urate Genetics Consortium (GUGC) genome-wide association study. Data from the Study for Updated Gout Classification Criteria (SUGAR) were randomly divided into development and test data sets. A data-driven case definition was formed using logistic regression in the development data set. This definition, along with definitions used in GUGC studies and the 2015 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) gout classification criteria were applied to the test data set, using monosodium urate crystal identification as the gold standard.
  
  
  
  For all tested GUGC definitions, the simple definition of "self-report of gout or urate-lowering therapy use" had the best test performance characteristics (sensitivity 82%, specificity 72%). The simple definition had similar performance to a SUGAR data-driven case definition with 5 weighted items: self-report, self-report of doctor diagnosis, colchicine use, urate-lowering therapy use, and hyperuricemia (sensitivity 87%, specificity 70%). Both of these definitions performed better than the 1977 American Rheumatism Association survey criteria (sensitivity 82%, specificity 67%). Of all tested definitions, the 2015 ACR/EULAR criteria had the best performance (sensitivity 92%, specificity 89%).
  
  
  
  A simple definition of "self-report of gout or urate-lowering therapy use" has the best test performance characteristics of existing definitions that use routinely available data. A more complex combination of features is more sensitive, but still lacks good specificity. If a more accurate case definition is required for a particular study, the 2015 ACR/EULAR gout classification criteria should be considered.
authors.affiliation: University of Auckland, Auckland, New Zealand.
authors.forename: Nicola
authors.initials: N
authors.lastname: Dalbeth
authors.affiliation: University of Pennsylvania, Philadelphia.
authors.forename: H Ralph
authors.initials: HR
authors.lastname: Schumacher
authors.affiliation: Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Jaap
authors.initials: J
authors.lastname: Fransen
authors.affiliation: Boston University School of Medicine, Boston, Massachusetts.
authors.forename: Tuhina
authors.initials: T
authors.lastname: Neogi
authors.affiliation: Viecuri Medical Center, Venlo, The Netherlands.
authors.forename: Tim L
authors.initials: TL
authors.lastname: Jansen
authors.affiliation: University of Otago, Wellington, New Zealand.
authors.forename: Melanie
authors.initials: M
authors.lastname: Brown
authors.affiliation: Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Worawit
authors.initials: W
authors.lastname: Louthrenoo
authors.affiliation: Hospital General de Mexico, Mexico City, Mexico.
authors.forename: Janitzia
authors.initials: J
authors.lastname: Vazquez-Mellado
authors.affiliation: Nasonova Research Institute of Rheumatology of Russia, Moscow, Russia.
authors.forename: Maxim
authors.initials: M
authors.lastname: Eliseev
authors.affiliation: Geraldine McCarthy, MD, FRCPI, University College Dublin School of Medicine and Medical Science, Dublin, Ireland.
authors.forename: Geraldine
authors.initials: G
authors.lastname: McCarthy
authors.affiliation: University of Otago, Christchurch, New Zealand.
authors.forename: Lisa K
authors.initials: LK
authors.lastname: Stamp
authors.affiliation: Hospital Universitario Cruces & BioCruces Health Research Institute, Vizcaya, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Perez-Ruiz
authors.affiliation: Hospital General Universitario de Elda, Alicante, Spain.
authors.forename: Francisca
authors.initials: F
authors.lastname: Sivera
authors.affiliation: Université Paris Diderot, Sorbonne Paris Cité, UFR de Médecine, INSERM, UMR 1132, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris, and Hôpital Lariboisière, Paris, France.
authors.forename: Hang-Korng
authors.initials: HK
authors.lastname: Ea
authors.affiliation: Westfries Gasthuis, Hoorn, The Netherlands.
authors.forename: Martijn
authors.initials: M
authors.lastname: Gerritsen
authors.affiliation: Carlo A. Scire, MD, PhD, Italian Society for Rheumatology, Milan, Italy.
authors.forename: Carlo A
authors.identifier: 0000-0001-7451-0271
authors.initials: CA
authors.lastname: Scire
authors.affiliation: University and IRCCS Policlinico S. Matteo Foundation, Pavia, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Cavagna
authors.affiliation: Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: Chingtsai
authors.initials: C
authors.lastname: Lin
authors.affiliation: Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: Yin-Yi
authors.initials: YY
authors.lastname: Chou
authors.affiliation: University Hospital Carl Gustav Carus, Dresden, Germany.
authors.forename: Anne-Kathrin
authors.initials: AK
authors.lastname: Tausche
authors.affiliation: Universidade de Estado do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Geraldo
authors.initials: G
authors.lastname: da Rocha Castelar-Pinheiro
authors.affiliation: Rijnstate Hospital, Arnhem, The Netherlands.
authors.forename: Matthijs
authors.initials: M
authors.lastname: Janssen
authors.affiliation: China Medical University School of Medicine, Taichung, Taiwan.
authors.forename: Jiunn-Horng
authors.identifier: 0000-0001-9292-5964
authors.initials: JH
authors.lastname: Chen
authors.affiliation: University of Genoa, Genoa, Italy.
authors.forename: Marco A
authors.initials: MA
authors.lastname: Cimmino
authors.affiliation: Diakonhjemmet Hospital, Oslo, Norway.
authors.forename: Till
authors.initials: T
authors.lastname: Uhlig
authors.affiliation: University of Otago, Wellington, New Zealand.
authors.forename: William J
authors.identifier: 0000-0001-6075-8479
authors.initials: WJ
authors.lastname: Taylor
mesh_terms: D003078:Colchicine / Q000627:therapeutic use; D059026:Diagnostic Self Evaluation; D016021:Epidemiologic Studies; D005260:Female; D006073:Gout / Q000145:classification* / Q000652:urine; D006074:Gout Suppressants / Q000627:therapeutic use; D006801:Humans; D033461:Hyperuricemia / Q000145:classification / Q000652:urine; D016015:Logistic Models; D008297:Male; D012680:Sensitivity and Specificity; D063189:Symptom Assessment / Q000379:methods*; D014527:Uric Acid / Q000652:urine
chemical_list: D006074:Gout Suppressants; D014527:Uric Acid; D003078:Colchicine