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Para los autores del artículo, del Dana-Farber Cancer Institute de Boston (Estados Unidos), no existe suficiente evidencia que apoye esa creencia, basándose en el análisis de 24 investigaciones publicadas al respecto. En conjunto, analizaron 26 comparaciones entre pacientes con cáncer incluidos y no incluidos en ensayos clínicos.
De esas comparaciones, en 14 se obtuvo alguna evidencia de que la participación en el estudio se relacionó a mejores resultados para el paciente, pero tales comparaciones a menudo contienen defectos de metodología, a juicio de los autores. De hecho, comentan que sólo 8 de las comparaciones analizados utilizaron pacientes no participantes en ensayos clínicos comparables a pacientes sí incluidos en alguna de estas investigaciones. De ellas, sólo en tres se puso de manifiesto un beneficio para los participantes respecto a los no participantes.
Webs Relacionadas
The Lancet
http://www.thelancet.com/
Dana-Farber Cancer Institute
http://www.dfci.harvard.edu/