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Deslizamientos en el tamaño de la muestra en ensayos aleatorios: exclusiones y los perdidos y descarriados
Kenneth F Schulz1, David A Grimes
1Family Health International, PO Box 13950, Research Triangle Park, NC 27709, USA. KSchulz@fhi.org
Lancet (London, England)
|March 13, 2002
Resumen
Un análisis adecuado del ensayo clínico requiere incluir a todos los participantes aleatorizados. La mala gestión de las exclusiones, incluso con buenas intenciones, puede socavar la validez y la generalización del estudio.
Área de la Ciencia:
- Los ensayos clínicos son ensayos clínicos.
- La bioestadística es la bioestadística.
- Metodología de investigación Metodología de investigación.
Sus antecedentes:
- La aleatorización es crucial para las comparaciones imparciales de tratamientos en ensayos clínicos.
- La adherencia y retención de los participantes son desafíos significativos que afectan la integridad del ensayo.
- Las exclusiones posteriores a la aleatorización pueden comprometer la validez de los resultados.
Objetivo del estudio:
- Para enfatizar la importancia de incluir a todos los participantes aleatorizados en el análisis primario.
- Para resaltar los sesgos potenciales introducidos por la exclusión de los participantes después de la aleatorización.
- Para guiar a los investigadores sobre las mejores prácticas para la retención de participantes y el análisis de datos.
Principales métodos:
- Discute los principios del análisis de intención de tratar (ITT) para los resultados primarios.
- Explica el impacto de los criterios de elegibilidad y las exclusiones posteriores a la aleatorización.
- Recomienda estrategias para maximizar la retención de los participantes y la transparencia de los informes.
Principales resultados:
- Excluir a los participantes después de la aleatorización, independientemente de la razón, puede introducir sesgo.
- El análisis de intención de tratar es el estándar de oro para el análisis primario para mantener los beneficios de la aleatorización.
- Los análisis secundarios (por protocolo, según el tratamiento) deben identificarse claramente como comparaciones no aleatorias.
Conclusiones:
- La estricta adherencia a la inclusión de todos los participantes aleatorizados en el análisis primario es esencial para los resultados válidos de los ensayos clínicos.
- Las medidas proactivas para maximizar la retención de los participantes y los informes transparentes son fundamentales.
- La mala gestión de las exclusiones plantea serios desafíos metodológicos que pueden socavar la validez del ensayo.
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