title: The use of self-report questions to examine the prevalence of musculoskeletal problems: a test-retest study.
abstract: BACKGROUND
  Case definition has long been an issue for comparability of results obtained for musculoskeletal pain prevalence, however the test-retest reliability of questions used to determine joint pain prevalence has not been examined. The objective of this study was to determine question reliability and the impact of question wording, ordering and the time between questions on responses.
  
  
  METHODS
  A Computer Assisted Telephone Interviewing (CATI) survey was used to re-administer questions collected as part of a population-based longitudinal cohort study. On two different occasions questions were asked of the same sample of 203 community dwelling respondents (which were initially randomly selected) aged 18 years and over at two time points 14 to 27 days apart (average 15 days). Reliability of the questions was assessed using Cohen's kappa (κ) and intraclass correlation coefficient (ICC) and whether question wording and period effects existed was assessed using a crossover design.
  
  
  RESULTS
  The self-reported prevalence of doctor diagnosed arthritis demonstrated excellent reliability (κ = 0.84 and κ = 0.79 for questionnaires 1 and 2 respectively). The reliability of questions relating to musculoskeletal pain and/or stiffness ranged from moderate to excellent for both types of questions, that is, those related to ever having joint pain on most days for at least a month (κ = 0.52 to κ = 0.95) and having pain and/or stiffness on most days for the last month (κ = 0.52 to κ = 0.90). However there was an effect of question wording on the results obtained for hand, foot and back pain and/or stiffness indicating that the area of pain may influence prevalence estimates.
  
  
  CONCLUSIONS
  Joint pain and stiffness questions are reliable and can be used to determine prevalence. However, question wording and pain area may impact on estimates with issues such as pain perception and effect on activities playing a possible role in the recall of musculoskeletal pain.
authors.affiliation: NHMRC Early Career Fellow, School of Medicine, Faculty of Health Sciences, The University of Adelaide, Level 7, SAHMRI, North Tce, Adelaide, SA, 5000, Australia. tiffany.gill@adelaide.edu.au.
authors.forename: Tiffany K
authors.initials: TK
authors.lastname: Gill
authors.affiliation: School of Medicine, Faculty of Health Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia. grtucker@adam.com.au.
authors.forename: Graeme R
authors.initials: GR
authors.lastname: Tucker
authors.affiliation: Population Research and Outcome Studies, Discipline of Medicine, Faculty of Health Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia. jodie.avery@adelaide.edu.au.
authors.forename: Jodie C
authors.initials: JC
authors.lastname: Avery
authors.affiliation: Rheumatology Department, Southern Adelaide Health Service, Repatriation General Hospital, Daws Rd, Daw Park, SA, 5042, Australia. michael.shanahan@sa.gov.au.|School of Medicine, Flinders University, Bedford Park, SA, 5041, Australia. michael.shanahan@sa.gov.au.
authors.forename: E Michael
authors.initials: EM
authors.lastname: Shanahan
authors.affiliation: School of Allied Health, College of Science, Health and Engineering, La Trobe University, Bundoora, Vic, 3083, Australia. h.menz@latrobe.edu.au.
authors.forename: Hylton B
authors.initials: HB
authors.lastname: Menz
authors.affiliation: Population Research and Outcome Studies, Discipline of Medicine, Faculty of Health Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia. anne.taylor@adelaide.edu.au.
authors.forename: Anne W
authors.initials: AW
authors.lastname: Taylor
authors.affiliation: School of Medicine, Faculty of Health Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia. robert.adams@adelaide.edu.au.|The Health Observatory, The Queen Elizabeth Hospital, The University of Adelaide, Adelaide, SA, 5005, Australia. robert.adams@adelaide.edu.au.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Adams
authors.affiliation: The Health Observatory, The Queen Elizabeth Hospital, The University of Adelaide, Adelaide, SA, 5005, Australia. catherine.hill@sa.gov.au.|Rheumatology Department, The Queen Elizabeth Hospital, Woodville Rd, Woodville, SA, 5011, Australia. catherine.hill@sa.gov.au.
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Hill
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000175:diagnosis* / Q000453:epidemiology*; D010147:Pain Measurement / Q000592:standards*; D015995:Prevalence; D015203:Reproducibility of Results; D057566:Self Report / Q000592:standards*; D011795:Surveys and Questionnaires / Q000592:standards; D055815:Young Adult