title: Development of multinational definitions of minimal clinically important improvement and patient acceptable symptomatic state in osteoarthritis.
abstract: OBJECTIVE
  The ability to interpret scores from patient-reported outcome measures at the individual patient level depends on the availability of valid, clinically meaningful benchmarks of response and state attainment. The goal was to develop multinational estimates for minimal clinically important improvement (MCII) and patient acceptable symptomatic state (PASS).
  
  
  METHODS
  A multinational sample of patients with osteoarthritis (OA) was evaluated before and 4 weeks after treatment with nonsteroidal antiinflammatory drugs. Patients completed either the Western Ontario and McMaster Osteoarthritis Index (WOMAC) numerical rating scale 3.1 (hip and knee OA) or the Australian/Canadian Index (AUSCAN) numerical rating scale 3.1 (hand OA) before and after treatment. Patients rated the clinical importance of their response to treatment and their satisfaction with the health state achieved, from which multinational MCII and PASS estimates were calculated for both the WOMAC and AUSCAN indices.
  
  
  RESULTS
  A total of 609 patients from 7 countries participated in the study. MCII and PASS estimates varied slightly by instrument and subscale. Absolute (percentage) change for MCII ranged 6-9 (10% to 17%) for WOMAC and 4-9 (8% to 15%) for AUSCAN. PASS estimates ranged 39-48 for WOMAC and 38-45 for AUSCAN. Some between-country variation was observed in MCII and PASS.
  
  
  CONCLUSIONS
  Preliminary multinational estimates for MCII and PASS have been developed for several countries. Further research is required to evaluate the robustness, temporal consistency, and age- and sex-dependency of the preliminary estimates as well as their generalizability to other countries, languages, cultures, regions, and other condition-specific outcome measures.
authors.affiliation: University of Queensland School of Medicine, Brisbane, Queensland, Australia, and Royal Brisbane and Women's Hospital, Herston, Queensland, Australia.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Bellamy
authors.affiliation: University of Maryland School of Medicine, Baltimore.
authors.forename: Marc
authors.initials: M
authors.lastname: Hochberg
authors.affiliation: Université Paris Diderot, Sorbonne Paris Cité, INSERM, UMR-S 1123, INSERM, CIC 1425-EC, UMR-S 1123, and AP-HP Hôpital Bichat, Paris, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Tubach
authors.affiliation: Hospital Universitario La Paz and Universidad Autónoma Madrid, Madrid, Spain.
authors.forename: Emilio
authors.initials: E
authors.lastname: Martin-Mola
authors.affiliation: Saint Joseph University Hôtel-Dieu de France, Beirut, Lebanon.
authors.forename: Hassane
authors.initials: H
authors.lastname: Awada
authors.affiliation: University of Toronto, Toronto General Research Institute, Institute for Work and Health, and Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Claire
authors.initials: C
authors.lastname: Bombardier
authors.affiliation: Mohammed Vth Souissi University, CNRST, and Laboratory of Information and Research on Bone Diseases (LIRPOS-URAC 30), Rabat, Morocco, and El Ayachi Hospital and University Hospital, Salé, Morocco.
authors.forename: Najia
authors.initials: N
authors.lastname: Hajjaj-Hassouni
authors.affiliation: Pfizer, Paris, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Logeart
authors.affiliation: Denothe Centre, University of Florence, Florence, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Matucci-Cerinic
authors.affiliation: Arthritis Center Twente, Medisch Spectrum Twente, and University Twente, Enschede, The Netherlands.
authors.forename: Mart
authors.initials: M
authors.lastname: van de Laar
authors.affiliation: Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Désirée
authors.initials: D
authors.lastname: van der Heijde
authors.affiliation: Paris Descartes University, Cochin Hospital, AP-HP, INSERM (U1153), PRES Sorbonne Paris-Cité, Paris, France.
authors.forename: Maxime
authors.initials: M
authors.lastname: Dougados
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D001315:Australia / Q000453:epidemiology; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D038622:Internationality; D007861:Lebanon / Q000453:epidemiology; D008137:Longitudinal Studies; D008297:Male; D009018:Morocco / Q000453:epidemiology; D010003:Osteoarthritis / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*; D010147:Pain Measurement / Q000379:methods / Q000592:standards*; D017060:Patient Satisfaction; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal