Conclusion Various methods have been used at all stages of CSPBM development .
The choice between developing a classification system de novo or from an existing instrument may depend on the availability of a suitable existing measure , while the choice between a decomposed or composite approach appears to be determined primarily by the purpose for which the instrument is design ed .
Background Health state utility values ( HSUVs ) are required to calculate quality -adjusted life-years ( QALYs ) .
They are frequently derived from generic preference-based measures of health .
However , such generic measures may not capture health attributes of relevance to specific conditions .
In such cases , a condition-specific preference-based measure ( CSPBM ) may be more appropriate .
Objective This systematic review aim ed to identify all published accounts of developing CSPBMs to describe and appraise the methods used .
Estimating a Preference-Based Index for an Eight-Dimensional Health State Classification System for Multiple Sclerosis.
BACKGROUND Condition-specific measures are frequently used to assess the health-related quality of life of people with multiple sclerosis ( MS ) . Such measures are unsuitable for use in economic evaluations that require estimates of cost per quality -adjusted life-year because they are not based on preferences . OBJECTIVES To report the estimation of a preference-based single index for an eight-dimensional instrument for MS , the Multiple Sclerosis Impact Scale - Eight Dimensions ( MSIS-8D ) , derived from an MS-specific measure of health-related quality of life , the 29-item Multiple Sclerosis Impact Scale ( MSIS-29 ) . METHODS We elicited preferences for a sample of MSIS-8D states ( n = 169 ) from a sample ( n = 1702 ) of the UK general population . Preferences were elicited using the time trade-off technique via an Internet-based survey . We fitted regression models to these data to estimate values for all health states described by the MSIS-8D . Estimated values were assessed against MSIS-29 scores and values derived from generic preference-based measures in a large , representative sample of people with MS . RESULTS Participants reported that the time trade-off questions were easy to underst and . Observed health state values ranged from 0.08 to 0.89 . The best-performing model was a main effects , r and om effects model ( mean absolute error = 0.04 ) . Validation analyses support the performance of the MSIS-8D index : it correlated more strongly than did generic measures with MSIS-29 scores , and it discriminated effectively between subgroups of people with MS . CONCLUSIONS The MSIS-8D enables health state values to be estimated from the MSIS-29 , adding to the methods available to assess health outcomes and to estimate quality -adjusted life-years for MS for use in health technology assessment and decision-making context
Conclusion Various methods have been used at all stages of CSPBM development .
The choice between developing a classification system de novo or from an existing instrument may depend on the availability of a suitable existing measure , while the choice between a decomposed or composite approach appears to be determined primarily by the purpose for which the instrument is design ed .
Background Health state utility values ( HSUVs ) are required to calculate quality -adjusted life-years ( QALYs ) .
They are frequently derived from generic preference-based measures of health .
However , such generic measures may not capture health attributes of relevance to specific conditions .
In such cases , a condition-specific preference-based measure ( CSPBM ) may be more appropriate .
Objective This systematic review aim ed to identify all published accounts of developing CSPBMs to describe and appraise the methods used .