[Propensity score methods for creating covariate balance in observational studies]. / Métodos de puntuación de propensión para crear una distribución equilibrada de las covariables en los estudios observacionales.
Rev Esp Cardiol
; 64(10): 897-903, 2011 Oct.
Article
en Es
| MEDLINE
| ID: mdl-21872981
ABSTRACT
Randomization of treatment assignment in experiments generates treatment groups with approximately balanced baseline covariates. However, in observational studies, where treatment assignment is not random, patients in the active treatment and control groups often differ on crucial covariates that are related to outcomes. These covariate imbalances can lead to biased treatment effect estimates. The propensity score is the probability that a patient with particular baseline characteristics is assigned to active treatment rather than control. Though propensity scores are unknown in observational studies, by matching or subclassifying patients on estimated propensity scores, we can design observational studies that parallel randomized experiments, with approximate balance on observed covariates. Observational study designs based on estimated propensity scores can generate approximately unbiased treatment effect estimates. Critically, propensity score designs should be created without access to outcomes, mirroring the separation of study design and outcome analysis in randomized experiments. This paper describes the potential outcomes framework for causal inference and best practices for designing observational studies with propensity scores. We discuss the use of propensity scores in two studies assessing the effectiveness and risks of antifibrinolytic drugs during cardiac surgery.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Ensayos Clínicos Controlados Aleatorios como Asunto
/
Puntaje de Propensión
Tipo de estudio:
Clinical_trials
/
Diagnostic_studies
/
Guideline
/
Observational_studies
Límite:
Humans
Idioma:
Es
Revista:
Rev Esp Cardiol
Año:
2011
Tipo del documento:
Article
País de afiliación:
Estados Unidos