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Methodological concerns in the exclusive human milk study

Journal of Perinatology volume 41, pages 910–911 (2021)Cite this article

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This letter highlights a few concerns from a recent observational study, where authors found that extremely low birth weight infants receiving exclusive human milk (EHM) had a significantly lower intraventricular hemorrhage (IVH) or peri-ventricular leucomalacia (PVL) [1].

The authors incorrectly infer the association between EHM and IVH or PVL in the adjusted analysis. They report that “the incidence of severe IVH or PVL is significantly lower in the EHM group than the non-EHM group (odds ratio 2.7; 95% confidence interval 1.2, 6.0; P = 0.012).” The odds ratio is 2.7, indicating a higher risk for severe IVH or PVL in the EHM group. It is unlikely to be true, and I presume the analysis is flipped. The authors should carefully reconsider the statistical analysis and provide the true estimate keeping all the factors mentioned above. The authors should also present the baseline differences of important confounders, such as volume-guarantee ventilation and prophylactic indomethacin, that can influence IVH or PVL.

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Fig. 1: Directed acyclic graph illustrating the direct and indirect path between exclusive human milk and intraventricular hemorrhage or peri-ventricular leukomalacia.

References

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Authors and Affiliations

  1. Division of Neonatology, Department of Pediatrics, Princess Nourah Bint AbdulRahman University, King Abdullah bin Abdulaziz University hospital, Riyadh, Saudi Arabia

    Abdul Razak

  2. Department of Pediatrics, McMaster University, Hamilton, ON, Canada

    Abdul Razak

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  1. Abdul Razak
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Correspondence to Abdul Razak.

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Razak, A. Methodological concerns in the exclusive human milk study. J Perinatol 41, 910–911 (2021). https://doi.org/10.1038/s41372-021-00947-5

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