An application of mixture distributions in modelization of length of hospital stay

Length of hospital stay (LOS) is an important indicator of the hospital activity and management of health care. The skewness exhibited by this variable poses problems in statistical modeling. The aim of this work is to model the variable LOS within diagnosis-related groups (DRG) through finite mixtu...

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Detalles Bibliográficos
Autores: Atienza Martínez, María Nieves, García Heras, Joaquín, Muñoz Pichardo, Juan Manuel, Villa Caro, Rafael
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2008
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/114724
Acceso en línea:https://hdl.handle.net/11441/114724
https://doi.org/10.1002/sim.3029
Access Level:acceso abierto
Palabra clave:Length of stay
Diagnosis-related groups
Finite mixture model
Gamma distributions
Weibull distributions
Lognormal distribution
Descripción
Sumario:Length of hospital stay (LOS) is an important indicator of the hospital activity and management of health care. The skewness exhibited by this variable poses problems in statistical modeling. The aim of this work is to model the variable LOS within diagnosis-related groups (DRG) through finite mixtures of distributions. A mixture of the union of Gamma, Weibull and Lognormal families is used in the model, instead of a mixture of a unique distribution family. Some theoretical questions regarding the model, such as the identifiability and study of asymptotic properties of ML estimators, are analyzed. The EM algorithm is proposed for performing these estimators. Finally, this new proposed model is illustrated by using data from different DRGs.