Written evidence submitted by Prof Ray Pawson (CLL0025)
Biographical details:
Emeritus Professor of Social Research Methodology, University of Leeds.
Author of several books and many papers on evidence-based policy.
Submission: A complex systems approach to crisis management.
Despite a mountain of epidemiological research, the policy response to Covid-19 has remained fragile. This contribution begins by drawing out some key lessons and then provides an analysis of the underlying complexities.
Lessons Learned
Summary
Whilst the world holds on to the promise of an effective vaccine and better clinical treatments, the first response to the pandemic has taken the form of what epidemiologists are inclined to term ‘non-pharmaceutical interventions’ (NPIs). This is a curious designation for it tells us what the response is NOT. And what the coronavirus response actually consists of is a massive array of public policies and social interventions. It is an unprecedented attempt to encourage and instil social and behavioural change on a grand scale. Such complex policy reforms are notoriously difficult to implement and evaluate. Parliamentarians will not need reminding of the decade of toil and trouble involved in shaping and reshaping the Universal Credit system.
This brings us to the question of how research can help in the design, execution, and assessment of such programmes. The first principle is to understand the nature of the beast, to grasp the complexity of the arduous journey from the ideas and inspirations of policymakers to the hearts and minds of the public. Herewith, a summary of those manoeuvres. The policy response …
Complexity abounds. What are the methodological implications? What limitations are placed on ‘the science’? There are two important consequences. I) Causal attribution is extremely taxing, II) Modelling the epidemic’s future is doomed to fail.
I. Causal attribution is the classic aim of applied science. It tackles the ‘what works?’ question. Put simply:
Have the assembled interventions succeeded in controlling the virus?
If the above analysis is correct, the causal question is transformed thus:
Has the interlocking and changing stockpile of adaptive, self-transforming interventions, each one with complex and sometimes contested guidance on its remit, as implemented and switched on and off by a changing array of central, local, private agencies, as digested by a diverse population containing people who comply, resist, learn, grow weary, change their minds, and seek exceptions, succeeded in controlling the virus?
Traditionally, causal analysis in non-experimental (i.e. population) studies operates by tracking the progress of an intervention against its outcomes (prevalence, deaths, etc). This can work reasonably well when intervention and outcomes are simple and singular. But when the intervention is a continually mutating conglomeration, the task becomes much more difficult. All we can say, is what is apparent at the time of writing (11.11.2020) – namely, that collectively the first broad configuration of interventions met with some success in controlling the virus, progress which then faltered as some of the components were removed, which prompted the assembly of a new package of interventions to combat wave 2, which may or may not go on to control the virus. We can chart the broad trends but what we cannot do, because the interventions are mutating, quarrelsome blobs, is to perform ‘contribution analysis’. We cannot pinpoint the crucial causal agents and their specific effects. We cannot say that ‘handwashing to the tune of happy birthday’ contributed to x% of the reduction in transmission, that ‘school closure’ accounted for y%, that the ‘rule of six’ generated z% improvement and so on.
In this respect it is also important to challenge the casual use of language which says that ‘lockdowns’ work. Lockdowns, firebreaks and so on are agglomerations (blobs of blobs). Lockdown 2 will not be the same as lockdown 1, nor is it the same as the lockdowns that have been tried across the world. To be sure, total lockdown (Wuhan style) might well work but only when applied unsparingly in a highly regimented and compliant population. The task in the UK remains that of tailoring and balancing lockdown’s many components in order to anticipate the changing response from its many publics. Trial-and-error is inevitable. Steady progress will follow from multiple, small gains in containing the most harmful micro-circuits of transmission.
II. Much of the early scientific advice on controlling the epidemic came from mathematical biology. Modellers figure significantly in the main SAGE committee, with a couple of dozen more on SPI-M. The modeller’s task is summarised in this figure.
Estimates are produced on the difference between ‘doing nothing’ (cases without protective measures) and ‘doing something’ (namely, the battery of interventions that might put in place). The crucial point is that these graphs are indeed estimates (or scenarios). The equations behind the progression curves are loaded with statistical assumptions about how people will behave under the different regimes. The committee will be aware of the OSR censure about treating scenarios as evidence and about the need to make the underlying assumptions more transparent. It is indeed the case that these crucial assumptions drive the models are often opaque and tucked away in footnotes and report annexes. But the real problem is that they are entirely simplistic.
The actual response to the virus programmes is captured in the intricate manoeuvres outlined in the seven bullet points above. That response, to repeat, is always in flux, is full of intended and unintended consequences, being shaped by the scores of influences and agencies as listed. No model can begin to imitate its complexities. Rather, the estimates driving the models come in the form dictated by the statistical apparatus. ‘Parameterization’, to use the jargon, thus tends to the fixed and mechanical - x% of population will comply with measure A; y% of hospital patients will require ICU treatment, z% of schools will close and so on. In a previous paper, I have scrutinised key assumptions from key models in great detail [1]. I provide a single example here. The influential report 9 of the Imperial College team [2], inserted the following estimate into their model. ‘30% of cases requiring hospitalisation will require critical care’. In model world, this leads to the alarming scenario that ICU provision will be rapidly overwhelmed. In the real world, real-time evidence revealed that the actual throughput was significantly smaller. The guesswork proved faulty and guesswork permeates these models. The fundamental principle, however, is that society’s response to research is always active rather than passive. Under the forecast of a surge in capacity requirements, the very first thing practitioners do is modify and improve local provision. Rather than predicting it, the model prompted behavioural and organisational change.
This brings us back to the core principle of this submission – social and behavioural change under virus interventions is complex, adaptive and self-transformative. Systems-based research methods [3, 4] should be at the forefront of the research effort and this would help sustain a more measured approach to crisis management.
References
[1] Pawson R. The Coronavirus Response: Boxed-in by Models. Evaluation Nov 5, 2020. Open Access. https://doi.org/10.1177/1356389020968579
[2] Ferguson N, et al. (2020) Report 9: Impact of non-pharmaceutical interventions (NPIs) to reduce COVID-19 mortality and healthcare demand. Available at: https:// www.imperial.ac.uk/media/imperial-college/medicine/sph/ide/gida-fellowships/Imperial-College-COVID19-NPI-modelling-16-03-2020.pdf
[3] Gates E (2016) Making sense of the emerging conversation in evaluation about systems thinking and complexity science. Evaluation and Program Planning 59: 62–73.
[4] Gerrits L and Verweij S (2015) Taking stock of complexity in evaluation: A discussion of three recent publications. Evaluation 21(4): 481–491.
Nov 2020