20-Item Short Form Survey (SF-20) calculator
About the score:
The SF-20 was originally published in 1988 as part of the Medical Outcomes Study (MOS), a comparative study of different healthcare delivery systems. It was originally published as the MOS short-form General Health Survey in the journal Medical Care.
The survey measures health across 6 domains: physical functioning (6 questions), role functioning (2 questions), social functioning (1 question), mental health (5 questions), health perceptions (5 questions), and pain (1 question).
Scores across each of these domains are reported on a 0% to 100% scale, with 0% representing the worst possible score in that domain and 100% the best possible score. Raw scores are transformed to fit the 0% to 100% interval as described in the original publication (note that for question #1 on general health, an initial transformation is performed as follows: 1 = 5, 2 = 4.36, 3 = 3.43, 4 = 1.99, 5 = 1). Reversal of scoring is completed as necessary such that the highest score always represents the best possible score. The exception to this scoring pattern is the pain score, for which 0% represents the best possible score and 100% the worst possible score.
The validity and reliability of the SF-20 were first established in 1989 in the Journal of the American Medical Association with the reporting of the MOS study results.
Stewart, Anita L., Ron D. Hays, and John E. Ware. “The MOS short-form general health survey: reliability and validity in a patient population.” Medical care 26.7 (1988): 724-735.
Stewart, Anita L., and Sandra D. Berry. “Functional Status and Well-being.” Jama 262 (1989): 907-13.
Carver, Daniel J., et al. “Validity and reliability of the Medical Outcomes Study Short Form-20 questionnaire as a measure of quality of life in elderly people living at home.” Age and ageing 28.2 (1999): 169-174.
About the score developer:
Dr. Anita Stewart, PhD, is Professor Emirta in the School of Nursing at UCSF within the Department of the Institute for Health Aging.
Through her career, she has studied health measurement across a variety of health-related domains, including physical functioning, mental health, general well-being, and social functioning. She also studies how health measurement differs across diverse populations.
To view her publications, please visit PubMed.