As an NHS doctor, I can tell you there's no cynical plot to distort coronavirus death certificates

These keyboard warriors love to tell the world that doctors sometimes write Covid-19 on certificates when there had not been a positive test – as if this is a revelation

The coronavirus pandemic has sparked many crazy conspiracy theories on social media. One of these is the notion that doctors issuing death certificates are either writing Covid-19 to inflate the overall numbers of deaths, or deliberately omitting it to play the numbers down.

The online warriors spouting such theories rarely have any background in healthcare, but they nevertheless seem equally confident in their claims that we medics are being financially incentivised to ramp up or play down the true figures on Covid-19 deaths, or are somehow pressurised by the authorities to breach our own professional codes. These conspiracy theorists and also love to tell the world that doctors sometimes write Covid-19 on certificates when there had not been a positive test, as if this is a revelation.

Improbably, given how notoriously hard we are to coerce or silence, we have allegedly all colluded en masse and hushed up this wrongdoing under threat of omerta, or because of our own greed or lack of professional values.

All of this is nonsense. As an NHS doctor, 31 years in the job, who has completed or supervised hundreds of death certificates, let me explain why.

When we complete certificates, they are structured with “cause 1a”, directly leading to death, and “cause 1b” and “1c”, representing other causes in that same chain that led to the death primarily cause by 1a. Then there is a “section 2”, for noting conditions contributing to the patient’s overall poor health, but not the direct cause of death at the time of their passing.

To illustrate with one example, we might write: “1a stroke, 1b hypertension, 1c diabetes and prostate cancer.”

Sometimes there is a cluster of simultaneous acute problems which we could easily switch as they all happened so close together and were all serious. But every doctor is instructed to complete the certificate “to the best of your belief and knowledge”. This means there are times where we are fairly sure of cause of death, but the definitive test is not yet confirmed or received. A heavy smoker with rapid weight loss and a mass on an X-ray who has died before there was time to get a lung biopsy might still receive a death certificate stating “1a lung cancer”.

For someone acutely ill with Covid-19, we will often write it as cause 1a. If a patient died from a pulmonary embolism caused by the virus, Covid-19 might appear as 1b. Or if they had been hospitalised by the virus, were recovering, but died weeks later from a different problem, it might appear in section 2.

Death certification has never been a precision science; sometimes post-mortems pick up problems we hadn’t listed at first. This is why measures like overall excess mortality, ranked against a five-year average for that month, will be important in analysing pandemic deaths. The Office for National Statistics (ONS) data we see reported on Covid-19 deaths does use the data on certificates but as individual doctors we are remote from this process.

There is no formal requirement to have a positive Covid-19 test back in order to write this on a death certificate. Bear in mind that first tests are often negative in people who later do turn out to have Covid-19. Testing was not widely available in the first few weeks of the pandemic; it is still often hard to access outside hospital.

In acute care we have become very used to how many patients with respiratory features of Covid-19 are present. There is a clear pattern based on symptoms, blood tests, observations, X-rays and the course of disease and even with a first test negative we continue to treat them as positive cases, including personal protective equipment and infection control measures. But as we started to test most adults admitted as emergencies, we also found plenty of positive cases who did not have those classical symptoms.

There are already rules about which cases we must routinely report to and discuss with coroners (for instance, violent deaths, notifiable or industrial diseases, recent surgery or patients unseen by anyone for days).

There is in hospital a new system of medical examiners – doctors independent of the patient’s care who work for some of each week scrutinising and discussing every certificate and speaking to bereaved families to discuss their loved one’s final days and answer any questions or concerns. This is being rolled out to community in due course. No doctors’ unions or colleges have objected to this independent oversight; in fact, we are supportive.

Doctors are not, contrary to some online claims, paid to write death certificates, so the notion of a monetary incentive for dodgy practice is nonsense. There is a standard £75 fee (in England) for completion of cremation forms which is a historical legacy. Many doctors feel uncomfortable taking it and often refuse. The cremation form and the certificate itself are legally binding documents and there could be serious consequence from General Medical Council or Criminal Law for falsification. And we are all conscious that when bereaved families receive the certificate they may be upset by its contents.

On occasion, following discussion with the coroner, certificates are altered if families feel they are misleading. We are also mindful that although post-mortems can clarify cause of death, they too can upset those grieving and delay funerals.

But seriously, why on earth would doctors have any desire to exaggerate Covid-19 deaths to justify government lockdown policy or to play the numbers down to protect the government’s reputation? There was no crime, and no motivation. We do still have professional ethics.

Professor David Oliver is an experienced NHS consultant physician, treating many patients with Covid-19. He is also a weekly columnist in the British Medical Journal and a former vice president of the Royal College of Physicians