Mapping the EQ-5D index by UPDRS and PDQ-8 in patients with Parkinson's disease.
Health Qual Life Outcomes
; 11: 35, 2013 Mar 08.
Article
in En
| MEDLINE
| ID: mdl-23497005
ABSTRACT
BACKGROUND:
Clinical studies employ the Unified Parkinson's Disease Rating Scale (UPDRS) to measure the severity of Parkinson's disease. Evaluations often fail to consider the health-related quality of life (HrQoL) or apply disease-specific instruments. Health-economic studies normally use estimates of utilities to calculate quality-adjusted life years. We aimed to develop an estimation algorithm for EuroQol- 5 dimensions (EQ-5D)-based utilities from the clinical UPDRS or disease-specific HrQoL data in the absence of original utilities estimates.METHODS:
Linear and fractional polynomial regression analyses were performed with data from a study of Parkinson's disease patients (n=138) to predict the EQ-5D index values from UPDRS and Parkinson's disease questionnaire eight dimensions (PDQ-8) data. German and European weights were used to calculate the EQ-5D index. The models were compared by R(2), the root mean square error (RMS), the Bayesian information criterion, and Pregibon's link test. Three independent data sets validated the models.RESULTS:
The regression analyses resulted in a single best prediction model (R(2) 0.713 and 0.684, RMS 0.139 and 13.78 for indices with German and European weights, respectively) consisting of UPDRS subscores II, III, IVa-c as predictors. When the PDQ-8 items were utilised as independent variables, the model resulted in an R2 of 0.60 and 0.67. The independent data confirmed the prediction models.CONCLUSION:
The best results were obtained from a model consisting of UPDRS subscores II, III, IVa-c. Although a good model fit was observed, primary EQ-5D data are always preferable. Further validation of the prediction algorithm within large, independent studies is necessary prior to its generalised use.
Full text:
1
Database:
MEDLINE
Main subject:
Parkinson Disease
/
Quality of Life
/
Surveys and Questionnaires
Type of study:
Prognostic_studies
Limits:
Female
/
Humans
/
Male
Language:
En
Journal:
Health Qual Life Outcomes
Journal subject:
SAUDE PUBLICA
Year:
2013
Type:
Article
Affiliation country:
Germany