VALIDATION DATA

Cronbach’s α of the SF-36v2 physical and mental summary components were 0.80 and 0.86 (eight scales range 0.73–0.92)

The test-retest assessment of the SF-36v2 subscales indicated excellent reliability, with an ICC of 0.80–0.95. The highest reliability was found between SF-36v2-PCS and SF-36v2-PF (r = 0.75), the lowest reliability was found between SF-36v2-PCS and SF-36v2-MH (r = 0.05).

Evidence from numerous focus group studies, formal cognitive tests, and from empirical studies in more than a dozen countries support the improvements in item wording and the changes in some terms used to identify health concepts adopted in Version 2.0. These improvements make the English-language SF-36 easier to understand and administer as well as making it more objective. Version 2.0 is also more comparable with translations of the SF-36. Because most of the improvements in item wording were developed during the process of translating and adapting the SF-36 for use in other countries during the International Quality of Life Assessment (IQOLA) Project, Version 2.0 is sometimes referred to as the “international version”.

The dimensional structure of the SF-36 (8 first-order and 2 higher-order factors) has been questioned in several studies. For example, higher-order factor analysis of the scale scores have confirmed separation of the scale scores into mental and physical health summary scores in some rheumatic studies, but not others. First-order factor analysis has also failed to confirm the 8-dimensional structure of the SF-36 in either exploratory or confirmatory factor analysis.