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 .
Integrating preferences into health status assessment for amyotrophic lateral sclerosis: The ALS Utility Index
We developed a preference‐based measure , the Amyotrophic Lateral Sclerosis Utility Index ( ALSUI ) , allowing computation of US population ‐based utility weights for the wide range of health states observed among ALS patients . A multi‐attribute utility approach was used . An ALS Health State Classification System was developed comprising the following attributes with different severity levels : Speech and Swallowing ( A1 ) ; Eating , Dressing , and Bathing ( A2 ) ; Leg Function ( A3 ) ; and Respiratory Function ( A4 ) . An internet‐based survey was administered to a r and om sample of the US population to assess preferences for ALS health states based on this system using  visual analog scale ( VAS ) and st and ard gamble ( SG ) questions . Using the VAS and SG data from 1374 individuals in the general population , utility functions were computed that corresponded to each severity level within A1 , A2 , A3 , and A4 . ALSUI scores for a given patient are computed by inputting his corresponding utility functions into the following multiplicative formula : ALSUI score = 1.06 × (A1 × A2 × A3 × A4)−0.06 on a scale where 0.0 reflects death and 1.0 reflects healthy . This study provides a useful tool for classifying ALS patients and determining a general public‐based utility score for ALS health states
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 .