Euro Surveill. 2020;25(19)
The abstract reads:
“In response to urgent needs for updated evidence for decision-making on various aspects related to coronavirus disease (COVID-19), the Norwegian Institute of Public Health established a rapid review team. Using simplified processes and shortcuts, this team produces summary reviews on request within 1–3 days that inform advice provided by the institute. All reviews are published with explicit messages about the risk of overlooking key evidence or making misguided judgements by using such rapid processes.”
It was the last sentence that amused me (note, my amusement is not in a good way). Later, the authors report:
“In the current situation, there is an urgent need for identifying the most important evidence quickly. Hence, we opted for this rapid approach despite an inherent risk of overlooking key evidence or making misguided judgements.”
The authors position is not unique and appears shared by a large swathe of systematic reviewers I’ve spoken to over the years. They appear so certain of their position, so sure that the systematic review is the right way, so sure they are infallible. The hubris is amazing for a supposedly scientific community – where scepticism should be the default.
A central point to this is that most systematic reviews miss lots of studies and even more data (by focusing on published journal articles). That is an evidence-based statements. So, given that, why do systematic reviews not come with an explicit message about the risk of overlooking key evidence? Is the stuff they miss not important? If so, where’s the evidence?
There are no ‘explicit messages’ on systematic reviews as that’s bad for business.
Now, let us show our faith by praying at the alter of the systematic review.