Reconsidering the inclusion of Ladapo’s work in the meta-analysis: Validity concerns and implications

ABSTRACT

This is a response to Marchand & Masoud’s response letter regarding my criticism “Response to Dr. Somovilla del Saz’s letter to the editor regarding “Risk of all-cause and cardiac-related mortality after vaccination against COVID-19: A meta-analysis of self-controlled case series studies.”” The response is a defense of the initial criticism to the paper regarding the validity of the inclusion of Ladapo´s paper.

I have read Marchand & Masoud’s response¹ attentively and I extend my gratitude to the authors for their response, granting me the opportunity to defend my initial critique. Here, I critique several points from the authors’ response:

The authors respond to my initial critique regarding whether Ladapo’s work underwent peer review by stating that the Florida Department of Health has established an internal review process. Upon thoroughly reviewing the Florida Department of Health website, detailed information about the specific guidelines or protocols used in their peer review process for works published solely on this platform was not found. This is crucial as transparency in peer review procedures is fundamental to validate the quality and credibility of research.

In their response, the authors highlight that my claims suggesting deliberate alterations to Ladapo’s work are serious and require substantiation with evidence. However, the authors overlook that in my original critique, I cite an article by Politico² compiling previous changes made to the final versions of Ladapo’s work. In this document, it is evident that sensitivity analyses and other analyses indicating that vaccines did not have a statistically significant relationship with mortality were removed. I will summarize the alterations made in each version, each version can be found in the last reference cited³:

Version 1: This version is the most distinct, with analysis periods differing from subsequent versions. In this version, no significant mortality risk is detected for any age group.

Version 2: Similar to the previous version, but it reports a slight increase in mortality following vaccination. Additionally, a comparison with COVID-19 is introduced, indicating that COVID poses a greater risk than the vaccine itself.

Versions 3, 4, and 5: In these versions, the report’s authors added sensitivity analyses to assess the robustness of significant findings. Upon applying sensitivity analysis in these three versions, the conclusion was that “COVID-19 vaccination was associated with a slight increased risk for cardiac-related mortality 28 days following vaccination in the primary analysis, but this association was attenuated and no longer significant when applying the event-dependent exposures model utilized for multidose vaccines.”

Clearly, Ladapo’s work was altered by removing key analyses that demonstrated no significant relationship between the vaccine and increased cardiac mortality. Consequently, I stand with initial primary critique questioning the validity of the meta-analysis, as Ladapo’s work should not have been included in the first place.

Funding Statement

The author(s) reported there is no funding associated with the work featured in this article.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions statement

Borja Somovilla del saz was solely responsible for all aspects of this letter.