Updated: Dec 22, 2020
For many years, countless strategy presentations looked forward to 2020 as a totemic year. It has been, but not for any of the reasons that we expected. As we look forward to better prospects in 2021, the year of the vaccines, it is both right and proper to recognise the toll of COVID-19 and our individual contributions and collective sacrifice, to different degrees, without which many more may not have been able to enjoy this subdued Christmas.
And yet now, over a year since the dawn of SARS-CoV-2, it is curious that the obsession continues with headline COVID-19 deaths statistics that are flawed. designed more to shock than inform, failing to provide perspective or insight. The UK Government declared that as of Saturday, 19 December, 67,075 individuals had died within 28 days of a positive COVID-19 test. This remains a bizarre way to estimate the terrible loss of this disease. It provides no direct information on the impact on different age groups or indeed the relative differences between men and women. It brackets together those where COVID would undoubtedly be the primary cause of death with those for whom, whether through accident or unrelated disease, COVID-19 had little to no effect. It likely misses many in the early months who died with symptoms but never received a test. This metric exists only because linked health and death records allow it to be calculated on a daily basis and published. It is a pity that the need for a daily figure gives this metric its limelight.
Death registrations and occurrences collated by the ONS on a weekly basis provide a more coherent and accurate picture, if somewhat lagged. The latest publication indicates that COVID-19 has appeared on 76,287 death certificates this year. These metrics are more likely to build understanding, but many consider excess deaths as the "gold standard" in assessing the impact of this pandemic. But let us be under no illusions. As excellently discussed in this excellent primer from Our World in Data, there is no single definition for how to calculate excess deaths.
The simplest approach is a weekly cumulative comparison of the total number of deaths in this year to the average number of deaths in, say, the last 5 years. This remains the approach used by the Economist that did so much to bring international comparisons of excess mortality to the attention of the world. As of the end of week 49, this approach would suggest 75,000 unexpected deaths so far this year. But it is not necessarily the most reliable or revealing. Perhaps there was something unusual about the mortality experience in the comparison period. No allowance is made for how changes in the population age pyramid over time may lead to a higher or lower number of expected deaths. Moreover, no explicit allowance is made for the general trend of improving or worsening mortality rates. And once again, we are faced normally by a single number which condenses the impact across age group and gender.
So in this first post at the start of a weekly series, let us put forward a method that attempts to address those issues, and provides the greater granularity that is needed in assessing the benefits of lockdowns and restrictions. In brief, the approach focuses on mortality rates, bringing together deaths from 5-year age groups and mid-year population estimates from the ONS, whilst making allowance for mortality improvements from the ONS 2018-based projections over the comparison period.
Graph 1 illustrates the pattern of excess deaths up to the end of week 49 across different age groups for men and women. In total, we estimate that there have been 65,000 unexpected deaths so far in 2020, driven by the direct and indirect impact of COVID-19, just over 38,000 men and around 27,000 women.
Graphs 2 and 3 use P-values to illustrate how the cumulative toll has built up over the year for different age groups, indicating how these excess deaths compare to the expected number of deaths. COVID-19 attacks multiple organs and hence our capacity to thrive. The higher number of deaths at older ages reflects that vulnerabilities and frailty are more widespread at those ages, not unique to those ages. We see from the graphs how relative mortality has increased for many age groups, and also how excess mortality fell after the initial wave in March to May, as COVID-19 was the tipping point for some.
The ONS has long provided analysis of the number of so-called "winter excess deaths" as a result of increased infections and greater vulnerabilities related to the cold and strains on the health service. COVID-19 and our collective reaction to the pandemic is changing behaviour and priorities. Over the coming weeks, we will track the levels of excess mortality across the different countries and regions within the UK, as the debate continues on how best to manage these coming months before deployed vaccines and the advent of spring start to exert downward pressure on hospitalisations and deaths.
But our continued focus on COVID-19 should not blind us to the reality that a further 575,000 have already lost their lives this year and will be remembered by families and friends this Christmas. Our collective attempts to dampen down the spread of the virus and limit its impact came at the worst possible time for them and their families. It will continue to be difficult to strike the right balance in the months to come, but balance there should be.