Amaia Bilbao1, Jesús Martín-Fernández2, Lidia García-Pérez3, Juan Carlos Arenaza4, Gloria Ariza-Cardiel5, Yolanda Ramallo-Fariña3, Laura Ansola6. 1. Osakidetza Basque Health Service, Basurto University Hospital, Research Unit, Bilbao, Spain; Health Service Research Network on Chronic Diseases, Bilbao, Spain; Kronikgune Institute for Health Services Research, Barakaldo, Spain. Electronic address: amaia.bilbaogonzalez@osakidetza.eus. 2. Health Service Research Network on Chronic Diseases, Bilbao, Spain; Oeste Multiprofessional Teaching Unit of Primary and Community Care, Primary Healthcare Management, Madrid Health Service, Madrid, Spain; Health Sciences Faculty, Rey Juan Carlos University, Madrid, Spain. 3. Health Service Research Network on Chronic Diseases, Bilbao, Spain; Fundación Canaria de Investigación Sanitaria, Santa Cruz de Tenerife, Tenerife, Spain. 4. Health Service Research Network on Chronic Diseases, Bilbao, Spain; Osakidetza Basque Health Service, Basurto University Hospital, Traumatology and Orthopedic Surgery Service, Bilbao, Spain. 5. Health Service Research Network on Chronic Diseases, Bilbao, Spain; Oeste Multiprofessional Teaching Unit of Primary and Community Care, Primary Healthcare Management, Madrid Health Service, Madrid, Spain. 6. Osakidetza Basque Health Service, Basurto University Hospital, Research Unit, Bilbao, Spain.
Abstract
OBJECTIVES: To map the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) onto the EQ-5D-5L in patients with hip or knee osteoarthritis (OA). METHODS: A prospective observational study was conducted on 758 patients with hip or knee OA who completed the EQ-5D-5L and WOMAC questionnaires, of whom 644 completed them both again 6 months later. Baseline data were used to derive mapping functions. Generalized additive models were used to identify to which powers the WOMAC subscales should be raised to achieve a linear relationship with the response. For the modeling, general linear models (GLM), Tobit models, and beta regression models were used. Age, sex, and affected joints were also considered. Preferred models were selected based on Akaike and Bayesian information criteria, adjusted R2, mean absolute error (MAE), and root mean squared error (RMSE). The functions were validated with the follow-up data using MAE, RMSE, and the intraclass correlation coefficient. RESULTS: The preferred models were a GLM with Pain2+Pain3+Function+Pain·Function as covariates and a beta model with Pain3+Function+Function2+Function3 as covariates. The adjusted R2 were similar (0.6190 and 0.6136, respectively). The predictive performance of these models in the validation sample was similar and both models showed an overprediction for health states worse than death. CONCLUSION: To our knowledge, these are the first functions mapping the WOMAC onto the EQ-5D-5L in patients with hip or knee OA. They showed an acceptable fit and precision and could be very useful for clinicians and researchers when cost-effectiveness studies are needed and generic preference-based health-related quality of life instruments to derive utilities are not available.
OBJECTIVES: To map the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) onto the EQ-5D-5L in patients with hip or knee osteoarthritis (OA). METHODS: A prospective observational study was conducted on 758 patients with hip or knee OA who completed the EQ-5D-5L and WOMAC questionnaires, of whom 644 completed them both again 6 months later. Baseline data were used to derive mapping functions. Generalized additive models were used to identify to which powers the WOMAC subscales should be raised to achieve a linear relationship with the response. For the modeling, general linear models (GLM), Tobit models, and beta regression models were used. Age, sex, and affected joints were also considered. Preferred models were selected based on Akaike and Bayesian information criteria, adjusted R2, mean absolute error (MAE), and root mean squared error (RMSE). The functions were validated with the follow-up data using MAE, RMSE, and the intraclass correlation coefficient. RESULTS: The preferred models were a GLM with Pain2+Pain3+Function+Pain·Function as covariates and a beta model with Pain3+Function+Function2+Function3 as covariates. The adjusted R2 were similar (0.6190 and 0.6136, respectively). The predictive performance of these models in the validation sample was similar and both models showed an overprediction for health states worse than death. CONCLUSION: To our knowledge, these are the first functions mapping the WOMAC onto the EQ-5D-5L in patients with hip or knee OA. They showed an acceptable fit and precision and could be very useful for clinicians and researchers when cost-effectiveness studies are needed and generic preference-based health-related quality of life instruments to derive utilities are not available.
Authors: Mojahed Shalhoub; Mohammad Anaya; Soud Deek; Anwar H Zaben; Mazen A Abdalla; Mohammad M Jaber; Amer A Koni; Sa'ed H Zyoud Journal: BMC Musculoskelet Disord Date: 2022-03-14 Impact factor: 2.362
Authors: Jesús Martín-Fernández; Mariel Morey-Montalvo; Nuria Tomás-García; Elena Martín-Ramos; Juan Carlos Muñoz-García; Elena Polentinos-Castro; Gemma Rodríguez-Martínez; Juan Carlos Arenaza; Lidia García-Pérez; Laura Magdalena-Armas; Amaia Bilbao Journal: Health Qual Life Outcomes Date: 2020-06-15 Impact factor: 3.186