The UK government is publishing a daily figure showing coronavirus deaths across the country.

There has been criticism that this number does not capture the true death toll from the illness.

Here’s what we know and what we don’t know about who is dying from Covid-19.

The daily death toll

The numbers of deaths from the English NHS and the devolved health authorities are published together on this website. It is updated every day.

These aren’t exactly “deaths caused by coronavirus”. It’s a bit more complicated than that.

The small print reads: “The figures shown are deaths in NHS services of patients who have had a positive test result for Covid-19… deaths of people who have had a positive test for Covid-19 could in some cases be due to a different cause.”

The numbers announced in this way only relate to hospitals, and always have done.

Time lag

Channel 4 News has reported on internal emails within a hospital trust raising concerns that the numbers of deaths staff are seeing each day are not reflected in the daily update.

NHS England’s explanation is that there is an inevitable time lag in the collection of data on deaths. If someone dies in hospital, there is a certification process, there might be a delay for a post-mortem, and staff will try to notify family members of the death. Relatives might not always be easy to track down.

These delays mean the news of a death may not feed into the numbers for several days. This fact is not made obvious on Public Health England’s coronavirus tracker website. But the NHS does break down the daily numbers by the actual date of death in figures circulated to journalists.

Deaths in the community

So far, we have been talking about deaths in hospitals. An obvious question is: how many people are dying without making it to hospital?

It’s possible that elderly and frail patients with coronavirus symptoms might decide, perhaps with input from relatives and doctors, to die at home or in a care facility without going to hospital. But if few patients outside hospitals are being tested, the diagnosis will be unconfirmed.

Until now, we haven’t been able to track these deaths, but the Department of Health and Social Care has told FactCheck it plans to publish data on Covid-19 related deaths in the community from tomorrow (Tuesday).

The independent ONS will publish weekly Covid-19 data from death registrations. This will hopefully give us more insight into coronavirus mortality outside hospitals, although we will have to wait until tomorrow to see what the limitations are.

Cause of death

Anecdotally, we’ve heard about a potential problem in counting deaths in the community. GPs who attend deaths have told @FactCheck that they are unsure about what to put as the cause of death on the patient’s death certificate.

If GPs do not have access to coronavirus testing kits, how can they be sure the patient died of the illness? Should they put Covid-19 down as the cause of death?

It’s not clear to FactCheck how big an issue this is around the country, and the government has told us that “death certificates can also indicate suspected Covid-19 as well as confirmed cases”.

The chief coroner issued guidance last week saying that Covid-19 “is an acceptable direct or underlying cause of death for the purposes of completing the Medical Certificate of Cause of Death”. The advice (which applies in England and Wales) does not say what GPs should do if they cannot test patients.

Doctors working in the community also have a statutory duty to report Covid-19 cases – even suspected ones – to Public Health England. This comes after the government added coronavirus to the list of “notifiable diseases”.

The verdict

We’ve seen people raising concerts that the official death toll under-reports the numbers of deaths from Covid-19 in the UK.

The numbers updated daily related to deaths in hospital. The daily tally might not match what staff in hospitals are seeing on that day, but there are a number of reasons why there is a lag in the reporting. We’ve seen no evidence that a large number of hospital deaths from coronavirus are going unreported by NHS authorities.

It’s true that some people may be dying at home or in care homes without being tested, and so don’t make it into official death toll.

The government intends to start including publishing data on deaths in the community from tomorrow, and we will see what effect it has on overall mortality.