Resumen
Los estudios ecológicos son uno de los diseños más frecuentemente empleados para tratar de establecer la asociación de ciertos factores con el desarrollo de enfermedades. Sin embargo, tienen limitaciones principalmente en la forma de realizar las mediciones de las variables, por lo que sus resultados tienen que ser comprobados con estudios de mayor calidad. Por lo tanto, el estudio recientemente publicado que vincula la posible relación entre una mayor mortalidad por COVID-19 y la no vacunación con el bacilo de Calmette-Guérin (BCG) queda en duda debido a la falta de rigurosidad en la metodología empleada.
Abstract
Ecological studies are one of the most common study designs used to establish the association between certain factors and disease development. However, they have limitations mainly on how to measure the variables, so their results must be verified in studies with greater validity. Therefore, the study that links the possible relationship between higher mortality from COVID-19 and non-vaccination by bacillus Calmette-Guérin (BCG) that was recently published, remains in doubt due to the lack of rigor in the methodology used.
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