Covid-19: Leading experts reflect on how data was used in the pandemic

composite image of data and covid

Eminent experts in statistics and data explain how they dealt with the unprecedented demand generated by the Covid-19 pandemic, discuss the validity of the 'follow the science' slogan, and reflect on the lessons learnt from a year of unprecedented change.

The impact of Covid-19 has tested and changed the actuarial profession in ways that are only now becoming apparent to its practitioners.

The first year of the pandemic was a numbers-driven crisis, with data- and risk analyses key to informing ministerial policy and the actions of government agencies, and ensuring that measures impacting on people were supported by evidence.

It has created many opportunities for actuaries and statisticians to enable better understanding and management of the crisis through informed perception and learning founded on their professional aptitudes. 

The IFoA’s recent webinar Beyond the Numbers: the use of data and statistics in informing policymaking during a pandemic focused on the use of data and statistics in informing government policy during the emergency. Its speaker panel brought together top UK experts in the fields of statistics and actuarial analytics with active roles in the UK’s Covid-19 response strategy.

Professor Sir Ian Diamond, head of the UK Office for National Statistics, opened the Beyond the Numbers discussion by outlining how the exponential spread of Covid-19 transformed the dynamics of data gathering, data analysis and the consumption of statistics.

Communicating the statistics

“The pandemic absolutely challenged the ONS’s role as provider of statistics for the government and public,” Professor Diamond said. “Society and economy moved quicker than anything we had seen previously. With this impetus, the key drivers for the ONS came down to two factors: pace and relevance.”

Public interest in the ONS’s analyses of the emergency soon caused it to realise the vital national importance its work was fast assuming. “The public visited the ONS website in numbers we could never have dreamt of before,” Professor Diamond said, “and we quickly felt a real responsibility to up our game, so that we would be sure of improving the communication of statistics in a compelling way.”

Panellist Sir David Spiegelhalter, Chair, Winton Centre for Risk and Evidence Communication, agreed. “The statistician Nate Silver has pointed out that numbers have ‘no way of speaking for themselves', that we ‘speak for them [and] imbue them with meaning’,” he said. “For me, this means that data does not give up its secrets automatically. You have to tell a story when you are communicating statistics.”

The pandemic “provided us with a case study of rapid decision-making under uncertainty,” agreed panellist IFoA Fellow Stuart McDonald, Head of Demographic Assumptions & Methodology for Lloyds Banking Group. “Throughout the crisis it’s been essential to make policy decisions based on the best available data rather than wait for ‘perfect’ information. Feedback on the consequences of those decisions often became apparent just a couple of weeks later – much sooner than had previously been the case with public health policy choices.”

Objective information

As the early waves of the pandemic struck, it became clear that the potential costs of inaction were extremely high, McDonald said, and they proved intolerably so, resulting in the unprecedented action to contain the spread of the virus by restrictions on our movement and freedoms. Policy-makers had to decide both what to do and what to say, with an awareness that public behaviours won’t be exactly in-line with the rules and guidance as communicated, and that these are not easy trade-offs.”

With many tough decisions to implement, the independent status of the data analysts constituted a valuable intermediary zone between government, stakeholders and public, Sir David pointed out. “Actuaries and statisticians tend not to have axes to grind,” he said. “Although at the start the media tried to push them into having strong opinions [about certain issues], they gave up on that after a while, and accepted that the public actually really love being helped to understand things.” The public’s appetite for objective information became the better story for them to report.

McDonald agreed: “Bayesian statistics was discussed in the mainstream media, as politicians and public endeavoured to get their heads around things like the varying probability that a positive COVID-19 test result really means a true infection.”

Reliable data and statistics are one of the UK’s “strengths”, McDonald added: “They have enabled us to understand the risk factors, identify new variants, to analyse the impact of control measures, and to roll-out vaccines in an effective manner – to name but a few of the challenges.”

Sir David’s further view was that public interest in statistics was, in part, fired up by a demand to know why their freedoms were being imposed on, and what personal behavioural changes they should – or should not – make in response to the government’s official rules.

“The public’s demands for data placed on statisticians, and the interest in it from the media, have been simply unprecedented,” said Sir David. “Statisticians should build on that to continue to push for a culture of transparency and openness around data – data that, actually, the public has a right to see [because] it’s information that relates both to the behaviours they are being forced to take on, and also the decisions they have to make themselves.”

Follow the science

‘Follow the science’ was to become somewhat of a rallying slogan for the government during the first months of its pandemic response. Its message intimated that validated science is essential to rational and equitable policymaking, with the implication that science makes the reasons behind those policy decisions evident. Although initially used in the context of medical science, ‘follow the science’ was less suitably applied to the field of statistics, opined the ‘Beyond the Numbers’ panellists.

“Science is, very rarely black and white,” said Professor Diamond. “In my observation, it is rare that two scientists completely agree. There is always nuance around science, and therefore simply saying ‘follow the science’ does not follow that the reason for doing something is going to be straightforward.”

For Sir David, ‘follow the science’ is anathematic.

“I loathe the phrase,” he declared. “It gives the impression that scientists are out there in front crying ‘follow me and I’ll tell you where to go’. They cannot do that. Pandemic responses, such as restricting personal freedoms and the like, entail political decision-making, he added, and for politicians to try and shift the responsibility onto scientists is unfair.”

“For policy to truly ‘follow the science’ it needs to change when the facts change,” McDonald pointed out. “That might not sit comfortably with politicians who are accustomed to changes in their stance being seized on as U-turns by their political opponents or the media.”

The pitfalls of ‘following the science’ notwithstanding, a need to quickly reach conclusions based on the rigorous multidisciplinary analysis of pandemic data as it entered public discourse, was one of the reasons that led to setting up the COVID-19 Actuaries Response Group, McDonald – one of its founders – explained. Formed in March 2020, the initiative comprises concerned actuaries, epidemiologists and longevity specialists, working together to help actuaries in thinking and responding to the COVID-19 crisis.

“Initially, we had no aspirations to communicate much wider than within our profession,” he explained. “We were aware that there would be an enormous amount of science becoming available, and also that decision-makers within the organisations we were employed by (and the clients that we advised) would need to reach conclusions very quickly. It occurred to us that there was real value to be had from having a small group of people with the relevant expertise going through that science centrally to disseminate points and key messages. As importantly, we would do that speaking in a language that busy stakeholders – like insurance executives and boards – would understand.”

Those stakeholders have come to include politicians and vertical sector experts; indeed, the pandemic has brought statisticians and actuarial analysts into contact with the ministerial machinery of policymaking as never before. It has been a salutary learning experience for both constituencies, McDonald believed.

Professor Diamond shared this view: “The actuaries and the statisticians have got together with other stakeholders, and worked hard to inform rigorously nuanced debates. We now have a proven opportunity for lasting change. The mantra we now have in ONS is ‘No going back’. We will continue to do things driven by pace and relevance as built-up over the last 12 months.”

His further hope is that by demonstrating its societal value during that period, the credentials and credibility established by statistics will promote a greater awareness of the importance of higher national levels of numeracy and data literacy.

“More than ever, we need a data literate population,” he said in his closing remarks.

Sir David also acknowledged “the enthusiasm for our subject among power-brokers and policymakers – there are many people out there who just want to know,” he said as ‘Beyond the Numbers’ was concluded, “and it’s a privilege to work in a profession that enables people to understand the world better, and therefore make better decisions. That’s a noble objective.”

Watch the full panel session, along with other webinars from the IFoA's Actuarial Innovation in the Covid-19 Era series.