Patient Disability Testing methods:

SF-36

The Short-Form 36 (SF-36) is a relatively brief and comprehensive generic, health status questionnaire developed and refined by the Medical Outcomes Study. The SF-36 has been designed to assess functioning and well-being in any patient group with chronic disease. It was designed for use in clinical practice and research, health policy evaluations, and general population surveys. This questionnaire can be self-administered, or administered during a face-to-face interview or by telephone. Thirty-six items in eight domains are included, which cover functional status, well-being, and overall evaluation of health:

• Physical function
• Social function
• Role limitations due to physical problems
• Role limitations due to emotional problems
• Mental health
• Energy/vitality
• Pain
• General health perception.

The SF-36 is scored from 0 to 100. However, unlike the PDQ-39, a higher score with SF-36 indicates a better perceived health status. The SF-36 has undergone a considerable amount of testing and has been demonstrated to have high levels of reliability and validity.

The SF-36 is able to distinguish between patients with PD (permanent disability) and the general population; patients with PD had significantly lower SF-36 scores than people without the disease. Therefore, the SF-36 can provide information on the impact of the disease in relation to an established ‘norm’. However, the SF-36 does not capture some of the prominent aspects of PD which impact upon the daily lives of patients, such as disturbances in concentration, difficulties in communication, and unusual bodily symptoms or discomfort. It has, therefore, been suggested that the SF-36 should be used with a disease-specific measure such as the PDQ-39.