Metodologí­a de Investigación
9 agosto 2023

El Cálculo del Tamaño Muestral en Ciencias de la Salud: Recomendaciones y Guía Práctica

Ruben Fernandez-Matias
a:1:{s:5:"es_ES";s:86:"Unidad de Investigación, Hospital Universitario Fundación Alcorcón, Madrid, España";}
Tamaño de la MuestraEstadísticaMetodologíaSample SizeStatisticsMethodology
Vol. 5 Núm. 1 (2023): Junio




El cálculo de tamaño muestral es uno de los aspectos más importantes en la planificación de la mayoría de las investigaciones, pudiendo derivar una muestra insuficiente a una inutilidad de la investigación en sí misma. Tradicionalmente se han utilizado los cálculos de tamaño muestral basados en potencia, pero actualmente se han empezado implementar los cálculos basados en precisión. En el presente escrito se presentan una serie de recomendaciones para cálculos para ensayos clínicos aleatorizados, modelos de regresión lineal y logística múltiples, análisis de reproducibilidad y de modelos predictivos multivariables, junto con algunos ejemplos prácticos de su implementación, así como algunas consideraciones con respecto a realización y utilización de datos de estudios piloto a la hora de planificar un cálculo de tamaño muestral.


Sample size calculation is one of the most important aspects in the planning of most research, and an insufficient sample can lead to the uselessness of the research itself. Traditionally, power-based sample size calculations have been used, but now precision-based calculations have begun to be implemented. This paper presents recommendations for calculations for randomised clinical trials, multiple linear and logistic regression models, reproducibility analysis, and multivariable predictive models, along with some practical examples of their implementation, as well as some considerations regarding the development and use of pilot study data when planning a sample size calculation.


  Cómo citar

Fernandez-Matias R. El Cálculo del Tamaño Muestral en Ciencias de la Salud: Recomendaciones y Guía Práctica. MOVE [Internet]. 9 de agosto de 2023 [citado 19 de mayo de 2024];5(1):481-503. Disponible en:


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