Why are people not self-isolating?

“Research conducted for the Department of Health found that only 11% of people asked to self-isolate by NHS Test and Trace have done so.”

Annaliese Dodds MP, 17 November 2020

“It is estimated that only about 11% of people self-isolate when they are asked to do so—11%. That is not because they do not want to; it is because many do not feel that they can afford to do so.”

Sir Keir Starmer MP, 18 November 2020

“At the moment only 11% of people who are asked to self-isolate through the NHS app are actually able to do so, many of them not eligible for a one-off payment to help them do that.”

Lisa Nandy MP, 29 November 2020

“We still need to fix the gaps in contact tracing and in financial support for those who need to self-isolate. Only 11% of people are being contacted, according to the figures that I am getting.”

Bill Esterson MP, 8 December 2020

We’ve seen several Labour MPs use an 11% figure to talk about self-isolating in a variety of ways—which seem to be getting less accurate over time. We’ve written to the Labour party and will update this article with their response.

The number apparently originates in a government-funded research paper (not yet peer-reviewed), which sought to understand whether people were following the self-isolation rules.

The paper draws on data collected in a series of surveys from March this year until the beginning of August (although the data about test and trace only covers the last two months of this period, after the service launched).

In particular, the 11% figure seems to come from the finding that: “Of [the 405 people] who reported having been alerted by the NHS contact tracing service and told they had been in close contact with a confirmed COVID-19 case, 10.9% reported that they had not left home at all in the following 14 days.”

This means that it didn’t cover people who needed to self-isolate because they tested positive or had symptoms themselves.

Staying at home for 14 days was the minimum requirement for those self-isolating for this reason until 13 December. It has now been shortened to 10, although people who develop or continue to have Covid symptoms during this period may need to stay at home for longer. People are allowed in their gardens or private outdoor spaces during this time, but otherwise must stay inside “except in certain specific circumstances”. These include funerals, legal obligations and medical emergencies. 

The paper observed a slightly higher rate of self-isolation compliance, at 18.2%, among people who actually had Covid symptoms, and did not measure the proportion of people correctly self-isolating following a positive test.

The Shadow Chancellor, Annaliese Dodds, therefore used the 11% number correctly in a letter she wrote to the Chancellor on 17 November (as long as we understand her to mean people who are asked to self-isolate as contacts, not because they tested positive).

However, it is important to be clear about what the number means, and what it doesn’t.

Why did people break the rules?

Ms Dodds used the 11% figure as part of an argument that the government should expand the Test and Trace Support Payment (TTSP)—a scheme introduced in England and Wales in September to replace some of the lost income of eligible people who have to self-isolate.

However, the TTSP did not exist when the research she mentions was conducted, so it might have already improved the proportion of people self-isolating.

The researchers found that not following the self-isolation rules in general was associated with “men, younger age groups, having a dependent child in the household, lower socioeconomic grade, greater hardship during the pandemic, and working in a key sector.” They suggested that “Practical support and financial reimbursement is likely to improve adherence.”

However, the reasons people actually gave for not self-isolating do not suggest that they were primarily concerned about the financial cost of self-isolation.

Only 8.9% of those who reported not self-isolating correctly said it was “to go out to work”. Other reasons—such as not having symptoms, going to the shops, or not thinking the rule was necessary—were more common.

To be clear, self-isolation may have placed a financial burden on many people, and paying people to self-isolate may improve their adherence to the rules, but this research does not suggest that many people broke the rules for financial reasons.

It therefore does not support the Labour leader, Sir Keir Starmer’s claim during Prime Minister’s Questions on 18 November that when people do not follow the rules, “That is not because they do not want to; it is because many do not feel that they can afford to do so.”

Things were different in the summer

The Shadow Foreign Secretary, Lisa Nandy, also used a similar figure on the Andrew Marr Show on 29 November.

She said: “At the moment only 11% of people who are asked to self-isolate by the NHS app are actually able to do so, many of them not eligible for a one-off payment to help them do that.”

We have not yet heard back from Ms Nandy about the source for this figure, but if it comes from the same research, then her summary was not correct for several reasons.

As we have seen, the data in this research was collected up to the beginning of August, so it does not tell us about people’s behaviour “at the moment”, when she was speaking. For the same reason, it does not refer to people notified by the NHS contact tracing app, which was not launched until 24 September.

Ms Nandy was also wrong to say that only 11% of people were “able” to self-isolate when required to. The survey only asked them whether they did, not whether they could.

Are only 11% of contacts reached?

On 8 December, the Shadow Minister for International Trade, Bill Esterson, again used an 11% figure while talking about financial support for people who self-isolate, but this time it meant something entirely different.

Speaking in Parliament, he said: “We still need to fix the gaps in contact tracing and in financial support for those who need to self-isolate. Only 11% of people are being contacted, according to the figures that I am getting.” The Secretary of State for Health, Matt Hancock, replied that the true figure “is much higher than that”.

Mr Esterson has not yet replied to our question about where this figure comes from. It may be a mistake, in which he has muddled the percentage of people who said they did not self-isolate with the percentage of people who are contacted in the first place.

This second figure can be expressed in several different ways, some of them impossible to calculate precisely. In the latest statistics that were publicly available when Mr Esterson was speaking, 83.8% of close contacts of people who tested positive were reached and told to self-isolate (when communication details for those individuals were available).

If we look at all close contacts (including those without communication details) the figure is 72.5%.

Some infected people do not get tested, or cannot be reached, or do not provide any contacts, so an unknown number of other close contacts are missed by the tracing system. So it’s hard to say how much lower the figure would be if we took account of all them.

If this was the figure that Mr Esterson had in mind, then from the data available it does not seem possible for him or anyone else to know that it was 11%.