Conclusions The last 10 years has seen a substantial increase in the number of mapping studies and some evidence of advancement in methods with consideration of models beyond OLS and greater reporting of predictive ability of mapping functions
Background Mapping is an increasingly common method used to predict instrument-specific preference-based health-state utility values ( HSUVs ) from data obtained from another health-related quality of life ( HRQoL ) measure .
There have been several method ological developments in this area since a previous review up to 2007 .
Mapping the 25-item National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) to EQ-5D Utility Scores
Abstract Purpose : To develop a mapping algorithm for the estimation of EQ-5D-based utility scores from observed 25-item National Eye Institute Visual Functioning Question naire ( NEI VFQ-25 ) scores , a disease-specific , patient-reported outcome measure used in several retinal disorders to evaluate vision-specific functioning . Methods : The data set comprised 951 paired EQ-5D/NEI VFQ-25 observations from 344 patients in RESTORE , a 12-month , r and omized , double-blind trial in individuals with visual impairment due to diabetic macular edema .  EQ-5D index scores ( utilities ) were calculated based on the UK tariff . We evaluated 11 models using predictor sets based on the NEI VFQ-25 subscales to estimate utility as a function of NEI VFQ-25 score , based on four modeling techniques . Model performance was assessed by 10-fold cross-validation comparing root mean squared error ( RMSE ) , mean absolute error ( MAE ) and correlation with EQ-5D score ( Pearson and Spearman correlation coefficients ) . Results : Mapping results were similar across all techniques and predictor sets . The reverse two-part generalized estimating equation model used fewest predictors and had the best predictive performance ( RMSE 0.200 , MAE 0.140 ) . Predicted and original EQ-5D values were not strongly correlated ( squared Spearman correlation coefficient , 0.34 ) . Conclusions : Although mapping disease-specific instruments to EQ-5D utilities is a preferred method by some reimbursement bodies , finding an appropriate mapping equation is not straightforward . In this study , mapping NEI VFQ-25 scores to EQ-5D utilities provided low predictive power , independent of the modeling methodology applied , suggesting an inability of the EQ-5D to discriminate vision-related activities , and highlighting that mapping exercises may lead to inaccurate utility values that do not represent patients ’ preferences
Conclusions The last 10 years has seen a substantial increase in the number of mapping studies and some evidence of advancement in methods with consideration of models beyond OLS and greater reporting of predictive ability of mapping functions
Background Mapping is an increasingly common method used to predict instrument-specific preference-based health-state utility values ( HSUVs ) from data obtained from another health-related quality of life ( HRQoL ) measure .
There have been several method ological developments in this area since a previous review up to 2007 .