Abstract
Background: Canadian normative data for the Medical Outcomes Study 36-item short form (SF-36) have recently been published. However, there is evidence from other countries to suggest that regional variation in health-related quality of life (HRQOL) may exist. We therefore examined the SF-36 data from nine Canadian centres for evidence of systematic differences.
Methods: Bayesian hierarchical modelling was used to compare the differences in the eight SF-36 domains and the two summary component scores within each of the age and gender strata across the nine sites.
Results: Five domains and the two summary component scores showed little clinically important variation. Other than a small number of exceptions, there was little overall evidence of HRQOL differences across most domains and across most sites.
Interpretation: Our finding of only a few small differences suggests that there is no need to develop region-specific Canadian normative data for the SF-36 health survey.
Résumé
Contexte: Les données normatives canadiennes s’appliquant à la version abrégée du questionnaire sur l’évolution médicale comportant 36 questions (SF-36) ont été publiées récemment. Toutefois, les données recueillies dans d’autres pays suggèrent qu’il peut exister des variations régionales au niveau de la qualité de vie reliée à l’état de santé (HRQOL). Nous avons donc étudié les données du SF-36 provenant de neuf centres canadiens pour démontrer les différences systématiques.
Méthodes: Un modèle hiérarchique bayésien a été utilisé pour comparer les différences entre les résultats des huit domaines du SF-36 et des deux composantes sommaires pour chaque strate d’âge et de sexe, et ce, pour les neuf centres.
Résultats: Les résultats de cinq domaines et des deux composantes sommaires démontraient des différences peu significatives cliniquement. Outre de rares exceptions, il y avait peu d’évidence de variations du HRQOL entre la plupart des domaines et des centres.
Interprétation: Les résultats obtenus, ne démontrant que de légères différences, suggèrent qu’il n’est pas nécessaire d’établir des données normatives spécifiques aux régions du Canada pour le questionnaire de santé SF-36.
Footnotes
Funding: The Canadian Multicentre Osteoporosis Study was funded by the Senior’s Independence Research Program, through the National Health Research and Development Program of Health Canada (Project No. 6605-4003-OS), The Medical Research Council of Canada, MRC-PMAC Health Program, Merck Frosst Canada Inc., Eli Lilly Canada Inc., Procter and Gamble Pharmaceuticals Canada Inc., Dairy Farmers of Canada
References
- 1.Ware JE. SF-36 Health Survey Manual and Interpretation Guide. Boston, Massachusetts: The Health Institute, New England Medical Centre; 1993. [Google Scholar]
- 2.Ware JE, Kosinski M K SD. SF-36 Physical and Mental Health Summary Scales: A User’s Manual. Boston, Massachusetts: The Health Institute, New England Medical Centre; 1994. [Google Scholar]
- 3.Ware JE. The SF-36 Health Survey. In: Spilker B, editor. Quality of Life and Pharmaco-economics in Clinical Trials. Philadelphia: Lippincott-Raven Publishers; 1996. pp. 337–45. [Google Scholar]
- 4.Berzon RA. Understanding and using health-related quality of life instruments within clinical research studies. In: Staquet MJ, Hays RD, Fayers FM, editors. Quality of Life Assessment in Clinical Trials: Methods and Practice. Oxford: Oxford University Press; 1998. pp. 3–15. [Google Scholar]
- 5.Hopman WM, Towheed T, Anastassiades T, Tenenhouse A, Poliquin S, Berger C, et al. Canadian normative data for the SF-36 Health Survey. CMAJ. 2000;163:265–71. [PMC free article] [PubMed] [Google Scholar]
- 6.Lyons RA, Fielder H, Littlepage NC. Measuring health status with the SF-36: The need for regional norms. J Public Health Med. 1995;17:46–50. [PubMed] [Google Scholar]
- 7.Wood-Dauphinee SW, Gauthier L, Gandek B, Magnan L, Pierre U. Readying a US measure of health status, the SF-36, for use in Canada. Clinical and Investigative Medicine. 1997;20:224–38. [PubMed] [Google Scholar]
- 8.Wood-Dauphinee SW. The Canadian SF-36 health survey: Normative data add to its value. CMAJ. 2000;163:283–84. doi: 10.1016/S1381-1169(00)00392-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Kreiger N, Tenenhouse A, Joseph L, MacKenzie T, Poliquin S, Brown JP, et al. The Canadian Multicentre Osteoporosis Study (CaMos): Background, rationale, methods. Can J Aging. 1999;18:376–87. doi: 10.1017/S0714980800009934. [DOI] [Google Scholar]
- 10.Statistics Canada provincial census data, 1991. Age, Sex and Marital Status: The Nation. Ottawa: Statistics Canada; 1993. [Google Scholar]
- 11.Statistics Canada provincial census data, 1991. Profile of Census Metropolitan Areas and Census Agglomeration, Part A. Ottawa: Statistics: Canada; 1993. [Google Scholar]
- 12.Raftery A, Lewis S. How many iterations in the Gibbs sampler? In: Bernardo JM, Berger JO, Dawid JO, Smith AFM, editors. Bayesian Statistics 4. Oxford: University Press; 1992. pp. 763–73. [Google Scholar]
- 13.Spiegelhalter DJ, Thomas A, Best NG, Gilks WR. BUGS: Bayesian Inference Using Gibbs Sampling. 1996. [Google Scholar]