The Short Form 36 (SF-36)
The Short Form-36 Health Survey (SF-36) is a 36-question patient-reported outcome survey of patient health. It’s a measure of overall health, as opposed to one that targets a specific disease or area of the body. This tool was developed by RAND in 1992 and derived from the Medical Outcomes Study (MOS), a multi-year study to explain variations in patient outcomes. A second version was developed in 1996 (SF-36v2) to correct deficiencies identified in the original version. Six-level response scales were reduced to five-level response scales in order to improve the two-role functioning scales.
The survey relies upon patient self-reporting and has eight (8) scaled sections: physical functioning, role limitations due to physical health, role limitations due to emotional problems, energy/fatigue, emotional well-being, social functioning, pain and general health. Each scale is transformed into a 0-100 scale on the assumption that each question carries equal weight. The lower the score, the more disability (i.e. a score of 0 equates to maximum disability).
The SF-36 is a widely used and accepted global health assessment measure. It has been proven useful in differentiating the health benefits produced by a wide range of different treatments. Oftentimes the SF-36 is paired with a more disease specific PRO. Many improvements were made to the SF-36v2 to shorten and simplify the wording and make it more familiar. It allowed for cultural adaptations widely used in the U.S.
Additionally, shorter versions of this tool are available: the SF-12 and SF-8. The SF-12 is likely to be a satisfactory alternative to the SF-36 when samples are large and the objective is to monitor overall physical and mental health outcomes. The SF-12 is also a widely used and accepted global health assessment measure.
When it comes to generating actual results, the scoring method is rather complicated to calculate. The SF-36 does not provide a single overall score, but rather eight (8) subscale scores and two (2) summary scores.
Since the SF-36 is a global health assessment, it frequently needs to be paired with a more specific PRO measure which can make the overall assessment process long. It has a low response rate in the >65 population. Additionally, as noted above, the scoring method is complicated.
Licensing and Cost
The SF-36 measure does not require a license, is available to the public, and is free to use, as long as you agree to the terms and conditions outlined by RAND. The survey questions and scoring instructions are available via the RAND website.
To learn more about the SF-36, please visit their website: www.rand.org.