Good grief. Will they never give up? A major new evidence review from the prestigious Royal Society has concluded that lockdowns, mask-wearing and other non-pharmaceutical interventions were “unequivocally” effective in cutting COVID-19 transmission. Is such a confident conclusion warranted? Of course not. But then, much of the work was carried out in China and Professor Neil Ferguson was one of the peer-reviewers, so what would you expect?
Released this morning, the report had the desired impact in the media. ‘Lockdowns and the ‘Rule of Six’ did slow the spread of Covid‘ declares the Mail.
‘Lockdowns and masks helped reduce transmission,’ announces the BMJ. “Non-pharmaceutical interventions (NPIs) were ‘unequivocally’ effective when rolled out in tandem during the Covid pandemic and led to ‘powerful, effective and prolonged reductions in viral transmission’, says a report by a team of experts brought together by the Royal Society,” it adds.
In the Times, Tom Whipple writes that the reduction from lockdowns was found to be “about 50%”:
The report involving more than 50 scientists from around the world, found that the strongest impact on coronavirus infections came from a full lockdown. Of 151 studies they considered that estimated an effect of stay at home orders, 119 found a substantial benefit, corresponding to a reduction in the ‘R number’ — the rate of spread of the virus — by about 50%.
And what about the harms, now widely accepted to be exceptionally high? That’s for others to look at, the report says. Why is it always someone else’s job to consider the harms? That was the excuse of SAGE and the Government advisers in 2020 and it’s the same excuse now from the Royal Society. To Whipple’s credit, he goes to Kevin McConway, Emeritus Professor of Statistics at the Open University to make this point. “They seem to be saying, simply, that this kind of assessment is out of scope [for] this piece of work. If not the Royal Society, who is actually going to do it?”
Prof. McConway also criticises the lack of higher quality studies, which he says should lead to some soul searching among scientists as it “shows up the work of scientists on NPIs during the pandemic in a rather unfavourable light”.
Indeed it does. Three and a half years after the advent of lockdowns and mask mandates, where are the properly designed and controlled studies to test the effectiveness and safety of these extreme interventions? Few and far between. Instead we just keep being served up the same low quality observational and modelling studies, which now the Royal Society bizarrely claims demonstrate an “unequivocal” reduction in the infection rate – reported by the Times to be in the region of 50%. This is the kind of spin and misinformation that we’ve all become tiresomely accustomed to since 2020, but don’t imagine the Trusted News Initiative and BBC Verify will jump into action any time soon. Misinformation is only a problem when it contradicts the official narrative, as we know.
Here’s how the report summarises its own conclusions, which is what most of the media reports are quoting:
In summary, evidence about the effectiveness of NPIs applied to reduce the transmission of SARS-CoV-2 shows unequivocally that, when implemented in packages that combine a number of NPIs with complementary effects, these can provide powerful, effective and prolonged reductions in viral transmission.
The report draws on six peer-reviewed evidence reviews commissioned by the Royal Society and published in a special edition of its in-house journal Philosophical Transactions A, which cover:
- Masks and face coverings
- Social distancing and lockdowns
- Test, trace and isolate
- Travel restrictions and controls across international borders
- Environmental controls
- Communication of NPIs in the U.K.
A closer look at the claims about face masks in particular gives a taste of the deep problems that beset this absurdly over-confident report.
Dr. Gary Sidley in the Daily Sceptic earlier today gave a good summary of the real state of evidence on face masks: “It is a long-established conclusion from the scientific world that face masks achieve no appreciable reduction in viral transmission.”
We knew this in 2015-16 with regard to surgeons and their patients (here and here). We knew this in 2020 from a gold-standard Cochrane review, an analysis of 14 studies on influenza and a healthcare investigation that concluded that masks “may paradoxically lead to more transmissions”. We knew this in 2021 based on the Danish mask study and two comprehensive evidence reviews (here and here). We knew this in 2022 in relation to primary schools and universities, and a debunking of premature pro-mask conclusions drawn from the Bangladesh study. And – as if more evidence was needed – at the start of 2023 we had the latest Cochrane review, yet again concluding that covering our faces with cloth and plastic does not significantly reduce the likelihood of contracting respiratory viral infections.
So what do the Royal Society researchers present to counter this wealth of high quality evidence? A whole pile of poor quality observational studies – the same ones that keep being recycled over and over as though mere repetition can polish the turd. They write (emphasis added here and below):
The investigation included 35 studies in community settings (three RCTs and 32 observational studies) and 40 in healthcare settings (one RCT and 39 observational). …
Most observational studies relied on self-reported mask wearing among participants (n=42/46; 91%). …
Results are not presented as a meta-analysis owing to the great heterogeneity in study design and the variety of outcome measures across the included studies. For the same reason of study design heterogeneity, formal GRADE assessment to assess the certainty of evidence was not universally applied. …
Although most of the numerous studies included in this review found that masks reduce transmission, almost all were at critical risk of bias in at least one of the domains embodied in ROB tools. In addition, the size of measured effects was variable and typically of low precision. …
Most of the studies included in this rapid systematic review were observational rather than experimental. Study designs commonly suffered from a critical risk of bias. The effects measured in each study were variable in magnitude and generally of low precision. Nevertheless, the weight of evidence from all studies suggests that wearing masks, wearing higher quality masks (respirators) and mask mandates generally reduced the transmission of SARS-CoV-2 infection.
Here’s the summary diagram from the report. I have circled the two gold-standard RCTs that show zero or near-zero significant effect. Note that the Abaluck Bangladesh study which found a small (12%) reduction in infections has been heavily criticised for its methodology, and in any case it found the effectiveness of cloth masks to be around zero. The rest of the studies were observational and at “critical risk of bias”, and so can tell us little of value.
If this is what the Royal Society deems to be “unequivocal” evidence of benefit then it plainly doesn’t understand the meaning of the word.
What about lockdowns and social distancing? According to the report, these were “associated with considerable reductions in community-level transmission of SARS-CoV-2 and the growth of the epidemic”.
Measures of greater stringency were typically associated with greater reductions in transmission during the COVID-19 pandemic, demonstrating what epidemiologists call a biological gradient. Stay-at-home orders, physical distancing measures, and restrictions on gathering sizes were repeatedly found to be associated with substantial community-wide reductions in SARS-CoV-2 transmission and were frequently assessed using the time-varying reproduction number, Rt. …
The body of evidence consistently pointed to substantial community-level benefits of social distancing measures for reducing SARS-CoV-2 transmission, preventing large-scale outbreaks, and controlling rapid epidemic growth. Stringent social distancing measures, whether applied to particular settings or to the entire population, were identified to be the most effective means of reducing transmission.
Was the quality of the evidence any better here? Nope. The study states: “As most of the evidence identified in this review came from observational studies, the quality or certainty of the evidence was mainly rated as low or very low for most studies.”
Furthermore, many of the studies found no benefit anyway:
Three studies did not find a significant association between stay-at-home orders and COVID-19 cases. However, the effectiveness of stay-at-home measures on reducing mortality was mixed, with 16 studies reporting reductions, and nine studies reporting no significant associations.
There was, however, “a multi-national analysis that looked at 210 countries in early 2020 found that stay-at-home orders reduced the incidence of COVID-19 by 11.2%”. Even if we accept this finding at face value (and there are lots of reasons not to, not least that the study came from China), an 11% cut in incidence of a very low-mortality disease as a result of imprisoning the population in their homes should be no-one’s definition of success.
The report also claims to have strong evidence that school closures reduce infections. This is despite the report itself noting that a “study examining schools in North Carolina and Wisconsin, U.S., from 2020 to 2021 did not observe an increase in the secondary transmission rate in schools after distancing measures were relaxed, indicating they had no effect on transmission in these schools”. But not to worry, models to the rescue: “The remaining simulation studies found that school measures were associated with reductions in public health impacts of COVID-19, both in the schools and the community.”
A look at just the first two studies cited in support of the claim about school closures shows the centrality of modelling. From the first: “We estimate the average dynamic effect of each intervention on the incidence of COVID-19 and on people’s whereabouts by developing a statistical model that accounts for the contemporaneous adoption of multiple interventions.” From the second: “Our main counterfactual experiments suggest that nationally mandating face masks for employees early in the pandemic could have reduced the weekly growth rate of cases and deaths by more than 10 percentage points in late April.” It’s safe to assume most of the studies will continue in this vein.
But should we really be surprised that this evidence review came down firmly in favour of lockdowns when the team the Royal Society commissioned to look at lockdowns and social distancing was based mainly in China, the country that pioneered the Covid lockdown? Nine of the 13 listed study authors, including the lead author, are said to work at the “World Health Organisation Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People’s Republic of China”.
What’s more, one of the peer-reviewers for the project was said to be Professor Lockdown – Imperial’s Dr. Neil Ferguson himself – almost literally marking his own homework.
It’s safe to say that this report offers nothing like “unequivocal” evidence of benefit from lockdowns, masks and other pandemic NPIs. As we have seen, in its more candid moments it admits that the results from studies vary considerably and the quality of the evidence from observational studies is low and typically at “critical risk of bias”.
Frankly, the Royal Society should be embarrassed to have put out such a skewed report that dresses up poor quality data as “unequivocally” supportive of the official stance on lockdowns and NPIs – a stance that is, not coincidentally, shared by the Chinese Government, which would have had a hand in the report via the Chinese researchers involved. It should be withdrawn and the misleading media reports corrected.
Stop Press: Professor Carl Heneghan came to much the same conclusion about this report in an interview with Julia Hartley-Brewer on TalkTV this morning.