Deriving SF-12v2 physical and mental health summary scores: a comparison of different scoring algorithms
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.Get Access
Summary scores for the SF-12, version 2 (SF-12v2) health status measure are based on scoring coefficients derived for version 1 of the SF-36, despite changes in item wording and response scales and despite the fact that SF-12 scales only contain a subset of SF-36 items. This study derives new summary scores based directly on SF-12v2 data from a recent U.S. sample and compares the new summary scores to the standard ones. Due to controversy regarding methods for developing scoring coefficients for the summary score, we compare summary scores produced by different methods.
We analyzed nationally representative U.S. data, which provided 53,399 observations for the SF-12v2 in 2003–2005. In addition to the standard SF-12V2 scoring algorithm, summary scores were generated using exploratory factor analysis (EFA), principal components analysis (PCA), and confirmatory factor analysis (CFA), with orthogonal and oblique rotation. We examined correlations among different summary scores, their associations with demographic and clinical variables, and the consistency between changes in scale scores and in summary scores over time.
The 8 scale means in the current data were similar to the 1998 SF-12v2 means, with the exception of the vitality scale. Correlations among the scales based on SF-12v2 data differed slightly from correlations derived from scales based on the SF-36 data. Correlations among summary scores derived using different methods were high (≥0.84). However, changes in summary scores derived using orthogonal rotation of components or factors were not consistent with changes in sub-scales, whereas changes in summary scores derived using oblique rotation were more consistent with patterns of change in sub-scales.
Although the basic structure of the SF-12 is stable, summary scores derived from oblique rotation are preferable and more consistent with changes in individual scales. On empirical and conceptual grounds, we suggest using summary scores based on oblique CFA.
- Ware, J. E., & Sherbourne, C. D. (1992). The MOS 36-item short-form Health Survey (SF-36): I conceptual framework and item selection. Medical Care, 30, 473–483. CrossRef
- Ware, J. E., Kosinski, M., & Keller, S. D. (1996). A 12-item short-form Health Survey: Construction of scales and preliminary tests of reliability and validity. Medical Care, 34, 220–233. CrossRef
- Ware, J. E., Jr., Kosinski, M., & Keller, S. D. (1994). SF-36 Physical and Mental Health Summary Scales: A user’s manual. Boston, MA: The Health Assessment Lab, New England Medical Center.
- Ware, J. E., Jr., Kosinski, M., Turner-Bowker, D. M., & Gandek, B. (2002). How to score version 2 of the SF-12 Health Survey. Lincoln, RI: QualityMetric Incorporated.
- Ware, J. E., Jr., Kosinski, M., Bjorner, J. B., Turner-Bowker, D. M., et al. (2007). Users manual for the SF-36v2 tm Health Survey (2nd ed.). Lincoln, RI: QualityMetric Inc.
- Jayasinghe, U. W., Proudofoot, J., Barton, C. A., Amoroso, C., et al. (2009). Quality of life of Australian chronically-ill adults: Patient and practice characteristics matter. Health and Quality of Life Outcomes, 7, 50. CrossRef
- Amir, M., Lewin-Epstein, N., Becler, G., & Buskila, D. (2002). Psychometric properties of the SF-12 (Hebrew version) in a primary care population in Israel. Medical Care, 40, 918–928. CrossRef
- Kontodimopoulos, N., Pappa, E., Niakis, D., & Tountas, Y. (2007). Validity of SF-12 summary scores in a Greek general population. Health and Quality of Life, 5, 55. CrossRef
- Gandhi, S. K., Salmon, J. W., Zhao, S. Z., Lambert, B. L., et al. (2001). Psychometric evaluation of the 12-item short form Health Survey (SF-12) in osteoarthritis and rheumatoid arthritis clinical trials. Clinical Therapeutics, 23, 1080–1098. CrossRef
- Montazeri, A., Vahdaninia, M., Mousavi, S. J., & Omidvari, O. (2009). The Iranian version of 12-item Short-Form Health Survey (SF-12): Factor structure, internal consistency and construct validity. BMC Public Health, 9, 341. CrossRef
- Maurischat, C., Herschbach, P., Peters, A., & Bullinger, M. (2008). Factorial validity of the short-form 12 (SF-12) in patients with diabetes mellitus. Psychology Science Quarterly, 50, 7–20.
- Preacher, K. J., & MacCallum, R. C. (2003). Repairing Tom Swift’s electric factor analysis machine. Understanding Statistics, 2(1), 13–43. CrossRef
- Velicer, W. F., & Jackson, D. N. (1990). Component analysis versus common factor analysis: Some issues in selecting an appropriate procedure. Multivariate Behavioral Research, 25(1), 1–28. CrossRef
- Widaman, K. F. (1993). Common factor analysis versus principal component analysis: Differential bias in representing model parameters? Multivariate Behavioral Research, 28(3), 263–311. CrossRef
- Simon, G. E., Revicki, D. A., Grothaus, L., & Vonkorff, M. (1998). SF-36 summary scores: Are physical and mental health truly distinct? Medical Care, 36(4), 567–572. CrossRef
- Taft, C., Karlsson, J., & Sullivan, M. (2001). Do SF-36 summary component scores accurately summarize subscale scores? Quality of Life Research, 10(5), 395–404. CrossRef
- Farivar, S., Cunningham, W., & Hays, R. (2007). Correlated physical and mental health summary scores for the SF-36 and SF-12 Health Survey. Health and Quality of Life Outcomes, 5, 54. CrossRef
- Anagnostopoulos, F., Niakas, D., & Tountas, Y. (2009). Comparison between exploratory factor-analytic and SEM-based approaches to constructing SF-36 summary scores. Quality of Life Research, 18, 53–63. CrossRef
- Wilson, D., Parsons, J., & Tucker, G. (2000). The SF-36 summary scales: Problems and solutions. Sozial- und Praeventivmedizin, 45, 239–246. CrossRef
- Hann, M., & Reeves, D. (2008). The SF-36 scales are not accurately summarized by independent physical and mental component scores. Quality of Life Research, 17, 413–423. CrossRef
- AHRQ PUF Data Files. MEPS HC-087: 2004 Medical Conditions. Rockville MD: Agency for Healthcare Research and Quality, November, 2006. Available at http://www.meps.ahrq.gov/mepsweb/data_stats/download_data/pufs/h87/h87doc.pdf. Accessed on May 1, 2009.
- Elixhauser, A., Steiner, C. A., Whittington, C. A., & McCarthy, E. (2000). Clinical classifications for health policy research: Hospital inpatient statistics, 1995. Healthcare Cost and Utilization Project, HCUP-3 Research Note. Rockville, MD: Agency for Healthcare Research and Quality. AHRQ PUB 98-0049.
- Cunningham, W. E., Nakazono, T. T., Tsai, K. L., & Hays, R. D. (2003). Do differences in methods for constructing the SF-36 physical and mental health summary measures change their associations with chronic medical conditions and utilization? Quality of Life Research, 12, 1029–1035. CrossRef
- Hays, R. D., & Morales, L. S. (2001). The RAND-36 measure of health-related quality of life. Annals of Medicine, 33, 350–357. CrossRef
- Ware, J. E., & Kosinski, M. (2001). Interpreting SF-36 summary health measures: A response. Quality of Life Research, 10(5), 405–413. CrossRef
- Schmitz, N., & Kuse, J. (2007). The SF-36 summary scores and their relation to mental disorders: Physical functioning may affect performance of the summary scores. Journal of Clinical Epidemiology, 60, 163–170. CrossRef
- Bentler, P. M., & Kano, Y. (1990). On the equivalence of factors and components. Multivariate Behavioral Research, 25(91), 67–74. CrossRef
- Mols, F., Pelle, A. J., & Kupper, N. (2009). Normative data of the SF-12 Health Survey with validation using postmyocardial infarction patients in the Dutch population. Quality of Life Research, 18, 403–414. CrossRef
- Fabrigar, L. R., Wegener, D. T., Maccallum, R. C., & Strahan, E. J. (1999). Evaluating the use of exploratory factor analysis in psychological research. Psychological Methods, 4(3), 272–299. CrossRef
- Cheak-Zamora, N. C., Wyrwich, K. W., & McBride, T. D. (2009). Reliability and validity of the SF-12v2 in the Medical Expenditure Panel Survey. Quality of Life Research, 18(6), 727–735. CrossRef
- Selim, A. J., Rogers, W., Fleishman, J. A., Qian, S. X., Fincke, B. G., Rothendler, J. A., et al. (2009). Updated U.S. population standard for the veterans RAND 12-item Health Survey (VR-12). Quality of Life Research, 18(1), 43–52. CrossRef
- Ware, J. E., Jr, Snow, K. K., Kosinski, M., & Gandek, B. (1993). SF-36 Health Survey: Manual and interpretation guide. Boston, MA: The Health Institute.
- Deriving SF-12v2 physical and mental health summary scores: a comparison of different scoring algorithms
Quality of Life Research
Volume 19, Issue 2 , pp 231-241
- Cover Date
- Print ISSN
- Online ISSN
- Springer Netherlands
- Additional Links
- Summary scores
- Factor analysis
- Industry Sectors
- Author Affiliations
- 1. Center for Cost and Financing Studies, Agency for Healthcare Research and Quality, Rockville, MD, 20852, USA
- 2. Center for Health Quality, Outcomes, and Economic Research (CHQOER), A Health Services Research and Development Center of Excellence, VA Medical Center, Bedford, MA, USA
- 3. Center for the Assessment of Pharmaceutical Practices (CAPP), Department of Health Policy and Management, Boston University School of Public Health, Boston, MA, USA
- 4. Section of Emergency Services, Boston VA Health Care System, West Roxbury, MA, USA
- 5. Boston University School of Medicine, Boston, MA, USA