Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2017 Apr-Jun;64(2):220-227.
doi: 10.29262/ram.v64i2.267.

[The research protocol V: The calculation of sample size]

[Article in Spanish]
Mario Enrique Rendón-Macías  1 , Miguel Ángel Villasís-Keever
Affiliations
Review

[The research protocol V: The calculation of sample size]

[Article in Spanish]
Mario Enrique Rendón-Macías et al. Rev Alerg Mex. 2017 Apr-Jun.

Abstract
in English, Spanish

Sample size refers to the number of participants to be included in a research study. If the calculation is carried out properly, not only conclusions will be established with statistical support and the potential risks to the subjects included in the investigation will be limited, but also the study can be properly planned to optimize economic and time costs. Calculation of sample size requires information that must be supported by the research protocol. This information includes that the objectives (descriptive study or a study to establish differences between groups) and hypotheses are well elaborated (with magnitude and direction), the scale of measurement of the outcome variable(s) must be defined, and type I error and type II error appropriately identified. This review describes how to specify the requirements needed for sample size calculation, including examples in clinical research designs.

El tamaño de la muestra se refiere al número de participantes que se incluirá en un estudio de investigación. Si se realiza adecuadamente el cálculo, no solamente se establecerán conclusiones con sustento estadístico y se limitarán los riesgos potenciales a los sujetos incluidos en la investigación, sino que además el estudio podrá planearse adecuadamente para optimizar costos económicos y tiempo. Para el cálculo del tamaño de la muestra se requiere información que debe estar sustentada en el protocolo de investigación; dicha información incluye que los objetivos (estudio descriptivo o para establecer diferencias), hipótesis (con magnitud y dirección) y escala de medición de la o las variables de desenlace estén bien planteadas, así como tener considerados los errores tipos I y II. En esta revisión se describe los requerimientos necesarios para el cálculo del tamaño de la muestra, incluyendo ejemplos en diseños de investigación clínica.

Keywords: Measurements, methods and theories; Research; Sample size.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

MeSH terms

LinkOut - more resources