Medical Outcomes Study 20-Item Short-Form Health Survey – MOS SF-20
Measures key dimensions of physical and mental health, functioning, and general health perceptions.
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. (1992). It is designed to measure Health-Related Quality of Life (HRQoL). 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 = Varies by item (see item text for specific response options).
The scale includes 10 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:
- Lower health status / higher limitations: 0 – 50
- Higher health status / lower limitations: 51 – 100
Psychometric Properties
Internal Consistency: The scale has demonstrated good to excellent internal consistency with reported Cronbach’s alpha values of Cronbach's alpha ranges from 0.76 to 0.88 across subscales.
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.