Medical Outcomes Study 20-Item Short-Form Health Survey (MOS SF-20)
Measures multi-dimensional health-related quality of life across physical, mental, and social functioning domains.
Scale Development & Technical Details
Scale Overview
The Medical Outcomes Study 20-Item Short-Form Health Survey (MOS SF-20) was developed by Stewart, A. L., Hays, R. D., & Ware, J. E., Jr. (1988). It is designed to measure Health-Related Quality of Life. The scale is intended for use with Adults.
Scale Structure
This instrument consists of 20 items organized into 6 factors/subscales: Physical Functioning, Role Functioning, Social Functioning, Mental Health, Health Perceptions, Pain.
| Factor / Subscale | Items | N |
|---|---|---|
| Physical Functioning | 2,3,4,5,6,7 | 6 |
| Role Functioning | 9,10 | 2 |
| Social Functioning | 11 | 1 |
| Mental Health | 12,13,14,15,16 | 5 |
| Health Perceptions | 1,17,18,19,20 | 5 |
| Pain | 8 | 1 |
Response Format
Respondents rate each item using a custom response format.
Response anchors: 1 = All of the time / Excellent / Limited > 3 months / Definitely true, 2 = Most of the time / Very good / Limited <= 3 months / Mostly true, 3 = A good bit of the time / Good / Not limited at all / Not sure, 4 = Some of the time / Fair / Mostly false, 5 = A little of the time / Poor / Definitely false, 6 = None of the time.
The scale includes 4 reverse-scored items to reduce acquiescence bias.
Scoring
Items are scored by subscale, with each subscale sum representing a distinct dimension.
Total scores range from 0 to 100. Interpretation guidelines:
- Subscale scores are transformed to a 0-100 scale, where higher scores indicate better health, functioning, or well-being.: 0 – 100
Psychometric Properties
Internal Consistency: The scale has demonstrated good to excellent internal consistency with reported Cronbach’s alpha values of 0.81 – 0.88.
Administration
The scale is self-administered and typically takes approximately 5 minutes to complete. It can be administered individually or in group settings. No special training is required for administration.