Abstract
Background: The SF‐12 is a widely used generic measure of subjective health. As the scoring algorithms of the SF‐12 do not include preference values, different approaches to assign a preference‐based index are available that should be tested regarding their feasibility and validity.
Objectives: To develop a concept for a preference‐based index for the SF‐12 on the basis of multi‐attribute decision analysis and to perform initial tests of its feasibility and validity in an empirical study.
Methods: A multi‐attribute preference function for the SF‐12 was developed, estimated and tested for validity. Two mail surveys (n = 100, 200) and an interview (n = 72) were conducted with women who had an operation for breast cancer. Visual analogue scale (VAS) and standard gamble (SG) measures elicited preference‐based valuations.
Results: Eight attributes were identified in the SF‐12. Validity tests showed an average difference of 8 VAS score points between directly measured and predicted values for given health states.
Conclusion: The initial results show that this approach might allow the direct assignment of a preference‐based valuation to the SF‐12. The quality of the psychometric features of the multi‐attribute value function is encouraging. Future studies should test this concept more extensively, especially by determining parameters for a representative sample of the general population and by comparing performance with other approaches to value the SF‐12. Copyright © 2005 John Wiley & Sons, Ltd.