Hernia mesh autoimmune reactions aren’t measured – it doesn’t mean they don’t exist! (Sling the Mesh, 26 October)

Summary

In this blog, Sling the Mesh discusses the powerful and thoughtful letter published in the journal Hernia by Nicholas T.H. Farr, titled “Absence of evidence is not evidence of absence – Rethinking NHS England’s inguinal hernia surgery decision aid.”

Content

Farr’s letter challenges a key statement in NHS England’s decision support tool (DST) for inguinal hernia surgery, which claims that “none” of the patients experienced allergic or autoimmune reactions to hernia mesh.

Farr rightly points out that such a definitive claim is not supported by the available evidence – and more importantly, that it misrepresents the uncertainty that still exists in the scientific literature.

“Saying there is no evidence of an event is not the same as stating the event did not occur.”

This distinction is vital. It goes to the heart of informed consent and patient trust.

Farr’s letter highlights that while manufacturers of mesh products often include warnings about potential allergic reactions in their Instructions for Use (IFUs), the DST fails to reflect this nuance. Instead, it presents a level of certainty that the evidence simply doesn’t justify.

Further reading on the hub from Nicholas Farr

• Medical device safety: effective testing is key