ABSTRACT
The objective of our study was to alert researchers to potential pitfalls involved
in analysis of a potential association between risk factors and development of disease.
We applied three different analytic methods-retrospective cohort study analyzed using
logistic regression, case-control analysis, and survival analysis with time-dependent
exposure-to retrospective data showing a correlation between histamine 2 (H2) blocker exposure and the occurrence of necrotizing enterocolitis in extremely low
birthweight neonates. Using case-control and survival analysis methods, there was
an apparent increase in necrotizing enterocolitis following exposure to H2 blocker treatment. The retrospective cohort method led to the opposite conclusion
because it failed to account appropriately for exposure. We concluded that the choice
of the analytic methodology used in a retrospective study is critical and should take
into account the timing and characteristics of the risk factors and condition under
investigation. Erroneous conclusions may be reached if inappropriate statistical methods
are used.
KEYWORDS
Statistical analysis - epidemiology - necrotizing enterocolitis
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Ronnie GuilletM.D. Ph.D.
Department of Pediatrics, Box 651, Golisano Children's Hospital at Strong
601 Elmwood Avenue, Rochester, NY 14642