I'm not sure whether we should carry on posting stuff about Heneghan in this thread, or create a separate thread about him. But he's got
another article in the Spectator written with his pal Tom Jefferson, and prompted by a
Danish RCT on face masks.
Heneghan and Jefferson wrote:In the end, there was no statistically significant difference between those who wore masks and those who did not when it came to being infected by Covid-19. 1.8 per cent of those wearing masks caught Covid, compared to 2.1 per cent of the control group. As a result, it seems that any effect masks have on preventing the spread of the disease in the community is small.
[my bolding]
It seems that a lot of people on social media have been pointing out that the bolded conclusion doesn't follow from the its premise, because the way masks prevent the spread of disease is mainly by preventing the wearer from infecting others, rather than by preventing the wearer from getting infected. The Spectator has been moved to add a rather tetchy correction to the bottom of the article (best read out in a Sybil Fawlty voice).
Spectator wrote:Due to the large number of people passing comment on the article on social media without reading it, we have updated the headline to emphasise that the study is about facemask wearers. Covid data can be found on our data hub: data.spectator.co.uk
As is generally the case with newspaper corrections, there's no way of knowing how the original article read, but presumably they had a misleading headline to go with Heneghan's misleading text.
To the credit of its authors, the abstract of the original Danish paper was quite upfront about its limitations.
Bundgaard et al. wrote:Limitation:
Inconclusive results, missing data, variable adherence, patient-reported findings on home tests, no blinding, and no assessment of whether masks could decrease disease transmission from mask wearers to others.
[my bolding again]
In six days the Lord made the heavens and the earth, the sea, and all that is in them. The human body was knocked up pretty late on the Friday afternoon, with a deadline looming. How well do you expect it to work?