The SF-36 is a multi-purpose, short-form health survey with only 36 questions. It yields an 8-scale profile of functional health and well-being scores, as well as psychometrically-based physical and mental health summary measures and a preference-based health utility index. It is a generic measure of perceived health status, as opposed to one that targets a specific age, disease, or treatment group. It is used to measure observable and tangible limitations due to poor health and/or bodily pain in physical, social, and role activities. Accordingly, the SF-36 has proven useful in surveys of general and specific populations, comparing the relative burden of diseases, and in differentiating the health benefits produced by a wide range of different treatments. Administration time is about 10-12 minutes. The SF-12 is an even shorter -- 1 page, 2 minute -- survey form that has been shown to yield summary physical and mental health outcome scores that are interchangeable with those from the SF-36.