The Centre for Evidence-Based Medicine (CEBM) is a centre within University of Oxford's Nuffield Department of Primary Care Health Sciences led by Professor Carl Heneghan, a GP and clinical epidemiologist. Prior to the pandemic, CEBM had a fine reputation as a one-stop-shop providing doctors with information on treatment options and their efficacy, free of the potential bias inherent in publications by pharmaceutical companies.

During the course of the pandemic Heneghan and Tom Jefferson have written a large number of pieces in the Spectator and Telegraph.

In spring 2020 they produced flawed estimates of the fatality ratio of Covid, which were far too low. In summer and autumn 2020 they pushed the idea that rising numbers of cases were really false positives and in September suggested Covid was in reality "waning fast". In October the pair gave a counterpoint to "dire warnings" that hospital admissions were rising, suggesting this was normal seasonal variation. In late October they said that excess deaths remained low, even as they began to rise significantly in reality. They then stopped discussing the issue.

During the course of the year Heneghan became a strong opponent and critic of most measures taken to control the virus. He attacked the rule of six ("no scientific evidence to back it up"), hospitality restrictions ("pubs and restaurants are one of the safest places to be"). He opposed local tiered restrictions, and opposed national restrictions too. He claims that "wearing masks in the community does not significantly reduce the rates of infection" (a flawed claim discussed here).

Initial phase and IFR underestimate

At the start of the pandemic, Heneghan's initial analyses in the BMJ were fairly measured. A key epidemiological question was what proportion of cases died from the new disease, and his article highlighted the difficulty in knowing exactly what the correct number of cases to divide the deaths by were, and praised the public health measures at that time.

However, within weeks, despite the emerging evidence of an IFR between 0.5% and 1% this prudent uncertainty had been replaced by certainty:

"Our current best assumption, as of the 22nd March, is the IFR is approximate 0.20% (95% CI, 0.17 to 0.25).

"... to estimate the IFR, we used the estimate from Germany’s current data 22nd March (93 deaths 23129) cases); CFR 0.51% (95% CI, 0.44% to 0.59%) and halved this for the IFR of 0.26% (95% CI, 0.22% to 0.28%) based on the assumption that half the cases go undetected by testing and none of this group dies."

This estimate had been taken by taking the lowest case fatality rate in Europe, without adjustment for any delay between infection and death, assuming no asymptomatic cases were being captured by testing, and thus diving both the CFR and the estimate by two.

Already, the team were producing work which ignored the mounting evidence of higher fatality rates - which they had reviewed - in favour of finger-in-the-air guesswork. A week later, this guesswork had become worse, with the addition of a further epicycle:

"However, the considerable uncertainty over how many people have the disease means an IFR of 0.26 is likely an overestimate... COVID-19 IFR could, therefore, be somewhere nearer to. 0.1%, if not lower."*

This departure from Evidence Based Medicine and into motivated guesswork and politics was, sadly, just the start. A week later, Heneghan and Jefferson published a piece entitled The Tipping Point, taking the unarguable point that not all cases were being captured by (at the time) limited testing to argue against lockdowns from an economic and government debt perspective:

"Nor can there be little doubt that the price of lockdown to society and economic paralysis is likely to be paid for generations to come. In the short term economic devastation seems certain, imposing a heavy penalty on us and probably successive generations.

"Lockdown is going to bankrupt all of us and our descendants and is unlikely at this point to slow or halt viral circulation as the genie is out of the bottle. What the current situation boils down to is this: is economic meltdown a price worth paying to halt or delay what is already amongst us?"

As summer began, the evidentiary basis for Heneghan and Jefferson's claims continued to deteriorate. Jefferson claimed the virus could have appeared from nothing, due to "human density or environmental conditions", claiming Western Samoans died of Spanish flu in 1918 despite no communication with the outside world; when a modicum of research would have indicated that Western Samoa caught the disease from a trading vessel. Outside of CEBM, Heneghan was claiming that "the current epidemic is a late seasonal effect in the Northern Hemisphere on the back of a mild ILI season".

False positives

Unfortunately, cases were soon on the rise again. Heneghan argued first that the rise in cases being observed was driven by an epidemic of false positives. In the Spectator he warned that the problem of false positives was so serious that Covid "might never be shown to disappear"

"To unravel the confusion, let’s think about what happens when the virus level is low – which it is in Britain at the moment. The latest ONS estimate is that about 0.04 per cent, or one in 2,300 people, had the virus at any point between 6 and 12 July. But for ease of calculation, let’s imagine the real infection level is higher: that 1 in 1,000 of us have the virus. Or 0.1 per cent.

"And let’s imagine again that, in this scenario, 10,000 random people go for a Covid-19 test. With the infection level at 0.1 per cent, just ten people will have Sars-CoV-2 and 9,990 will not. Of the ten who turn up with an infection, 80 per cent will test positive, meaning eight people will be correctly identified while two walk away with a false negative.

"And of the 9,990 not infected, all but ten will be correctly diagnosed as negative: hence the success rate of 99.9 per cent (the specificity). But ten will be told they have Covid-19, when in fact they don’t. That leaves us with 18 positive tests: eight from people who genuinely had the virus and ten who did not. So only eight out of 18 (44 per cent) of the infections are real. That’s where the chance of accurately detecting the disease being less than 50 per cent comes from [...]

"At very low prevalence, the proportion of people with infection falls and the numbers of falsely misdiagnosed increases. If Covid-19 completely disappears, then of our 10,000, no one will be infected. If you have followed the reasoning so far, you will have worked out this means that ten people would still be wrongly diagnosed as positive and the official data would show a national Covid-19 prevalence of 0.1 per cent. This is why understanding the accuracy of tests in the population that they are applied to matters: going off current testing practices and results, Covid-19 might never be shown to disappear."

In early August he wrote a piece in the Spectator headlined: "Why Covid cases in England aren’t actually rising", which argued that the apparent rise in postive tests was merely due to more testing and false positives.

Heneghan and Jefferson followed this with a piece in the Spectator on 13 August headlined: "Could mass testing for Covid-19 do more harm than good?" They argued that:

"With Covid-19, however, clinical diagnosis is seemingly a secondary consideration in the face of mass testing. All you require is a positive PCR test; no symptoms, no signs, no other diagnostic proof. But our limited understanding of mass testing and PCR suggests this might not suffice... when it comes to Covid-19, insufficient attention has been paid to how PCR results actually relate to disease... without a better understanding of what test results really show us, it seems that while coronavirus is at a low prevalence in our communities, mass testing might cause more harm than good".

On 1 Sepember, they wrote a piece in the Spectator headlined: "Coronavirus cases are mounting but deaths remain stable. Why?" Though cases were rising, they argued real circulation was "waning fast" and that PCR testing was just picking up "harmless virus particles":

"Evidence is mounting that a good proportion of 'new' mild cases and people re-testing positives after quarantine or discharge from hospital are not infectious, but are simply clearing harmless virus particles which their immune system has efficiently dealt with. Those whose immunity is more active are exactly in the age group of observed 'positives' and least likely to end with severe disease. So, we appear to have the reality of viral circulation, probably waning fast and the perceived reality of a misused and simply interpreted genial test"

On 7 September the pair wrote in the Spectator ("Covid-19 and the end of clinical medicine as we know it") complaining that positive tests had become meaningless, and about:

"inappropriate use of tests which cannot distinguish those who are infectious and require isolation from those who harbour remnants of the infectious agents. The patient has become a prisoner of a system labelling him or her as 'positive' when we are not sure what that label means."

In a further piece for the Spectator in October, ("Following the evidence for hospital admissions", which seems to have previously had a different title) the questioned whether we should rely on "dire warnings" that hospital admissions were rising, suggesting this was normal seasonal variation. We must not, they said, "jump to inappropriate conclusions". Covid admissions were, if anything, half what might be expected:

"The recent warnings of exponential growth of Covid-19 cases, inevitably followed by a rise in hospital admissions, is one focus of the Government's Covid messaging. Jeremy Hunt described this spike in admissions as a 'wake-up call' for the Government. But while this year the disease is newly identified, warnings of a winter crisis in the NHS occur annually. So should we be worried? For 20 years, 'influenza' has been blamed for putting hospitals under pressure in winter. Now, this fear has been substituted by 'Covid'.

"... should we rely on dire warnings that we are heading in the 'wrong direction'... The month of September sees around 21,000 cases of unforeseen attendances and admissions, which works out at around 700 unplanned admissions per day. However, by the end of September 2020, around 300 patients with covid were admitted in England per day. This is less than half of what we would normally expect... The current Covid projections need to be placed into context of the impact of the seasonal effect of the other respiratory pathogens. If we don’t, then we may jump to inappropriate conclusions."

The shift to advocacy against restrictions

On 14 September Heneghan wrote a piece in the Telegraph headlined: "Boris Johnson must bin the ‘rule of six’ and stop panicking":

"beset by anxieties, doubts and fear, and surrounded by a platoon of advisors, the PM has made one cautious, catastrophic error after another. Last week’s roll of the dice with the ‘rule of six’ could well be the policy that tips the British public over the edge. For it is a disturbing decision that has no scientific evidence to back it up"...Increased activity at the end of summer leads to an increase in acute respiratory infections, as it does every year. This is not rocket science....

"the decision to restrict gatherings belies a fundamental misunderstanding of what is happening with coronavirus in Britain. Admissions for Covid, critical care bed occupancies and deaths are now at an all-time low."...

"Cases are being over-diagnosed by a test that can pick up dead viral load; hospital admissions are subjective decisions made by physicians which can vary from hospital to hospital. Even deaths have been misattributed. Intervening with restrictive measures at the first sign of an upturn in cases means we are in for a long hard winter."

"The Government’s modelling predicts catastrophe. Yet this is wide of the mark. Cases will rise, as they will in winter for all acute respiratory pathogens, but this will not necessarily translate into excess deaths. In times of crisis, soothsayers are all the craze. Despite their consistently poor results, the Government keeps turning to models to inform its policymaking." [...]

"Our leaders amount to little more than a Dad’s Army of highly paid individuals with little or no experience of the job at hand. This inexperience leads to rash decisions and arbitrary policies.... Mr Johnson, we need you not to panic."