Statement about the Liverpool proposals for city-wide SARS-CoV-2 testing
5 November 2020
DR ANGELA ELIZABETH RAFFLE, Consultant in Public Health, Honorary Senior Lecturer Bristol Medical School Population Health Sciences, University of Bristol, BS8 2PL
The UK has over twenty years’ experience of delivering evidence-based, systematic, high quality screening programmes, which deliver more good than harm at affordable cost. I have specialised in researching, planning, delivering and quality assuring screening programmes for the last 35 years. I helped set up the National Screening Committee and worked as a Consultant to the National Screening Programmes since their inception in 1996.
Experience with screening tells us that if you embark on a screening programme without having carefully evaluated it first, without a proper quality assured pathway, without certainty of test performance in field settings, without full information for participants, and without the means to ensure that the intervention needed for those with positive results does indeed take place, the result is an expensive mess that does more harm than good.
Having looked carefully into what is being proposed, my assessment is that the current proposals for screening the City of Liverpool using SARS-CoV-2 rapid tests are not fit for purpose.
- It is called a ‘pilot’ yet there appears to be no research design.
- There is no concrete evidence that screening of this nature is helpful in outbreak control.
- It appears to have no system design for who is eligible, how they will be contacted, how they get results, what advice they will be given, how this will be followed up and how this will be integrated with test and trace and with local health and social care services.
- The tests being proposed are new, there is little data about their performance in field settings, and therefore many people will be given false results.
- The harm from false results includes unnecessary isolation (for false positives), and false reassurance with potentially riskier behavior (for false negatives).
My concerns are that the current proposals for city-wide screening will fail to realise any worthwhile benefit, and will cause substantial harm through diversion of resources. They will also distract from solving the widely reported problems with the test and trace programme.
It is my view that the National Screening Committee should be asked to rapidly review the proposals as a matter of urgency, in order that the plans can be subject to scrutiny by people with appropriate knowledge and experience.