Coronavirus (COVID-19) targeted community testing: national evaluation evidence and insights - final report

Executive Summary

Since January 2021, the Scottish Government have been working in partnership with Public Health Scotland (PHS), local authorities, NHS boards and others to deliver a targeted community testing (TCT) programme for the general public as part of a response to a recognised failure to identify a large proportion of positive cases. TCT is aimed at those without symptoms of coronavirus^[1] and without access to other asymptomatic^[2] testing pathways, such as Health and Social Care pathways or Education pathways. It is also aimed at providing symptomatic testing in places people are most likely to be positive.

The community testing evaluation sets out the evidence and key insights from a national perspective covering the period from its launch on 18 January 2021 to 26 September 2021. Community Testing was aimed at targeting areas where the virus rate is high, quickly rising (spiking), or has been identified as high risk to find positive cases that would not otherwise have been detected. It combined the use of PCR testing for symptomatic and asymptomatic cases, as well as developing capabilities to carry out asymptomatic testing with Lateral Flow Tests (LFT).

This evaluation focused on case identification, qualitative understanding of features of successful targeting and uptake, including public motivations and barriers. Some data and qualitative evidence were also captured on models and aspects of operational delivery. The evaluation has drawn mainly on published PHS data, alongside primary qualitative research with NHS Board and local authority partnerships.

Key findings

Public Health Impact – between 18 January and 26 September 2021, TCT conducted a combined total of 699,219 PCR and LFT tests, of which 93,466 were positive. Around a third (31%) of these cases were in those without symptoms. These are cases that may not otherwise have been detected in the continuing absence of symptoms, or were identified earlier than they otherwise would have been via PCR-based testing once symptomatic.

Testing uptake and change over time - The trend for overall TCT testing uptake (PCR and LFT), as indicated by weekly number of TCT tests conducted, has generally tracked a similar pattern to testing across Scotland, reflective of the changing incidence of COVID-19 and relaxation of restrictions. The one exception is a peak in early April for TCT testing which is not so evident for all Scotland testing. A possible explanation for this is an initial push to get the community asymptomatic test sites (ATS) operational, supported by military assistance. LFT testing grew sharply, peaking by 7th March. There was a sharp decline after the end of March coinciding with the cessation of military support, and tests then became universally available from 26th April through the Universal Offer.

Targeted testing: effective case finding - Due to the targeted nature of community testing, the expectation is that it should be more effective at finding positive asymptomatic cases than untargeted or general population testing. There are tentative indications that this has indeed been the case as demonstrated by the percentage of cases identified via LFT per number tested compared to other LFT pathways.

TCT had a percent LFT positive of 0.9% up to 21 September 2021 which is one of the highest of the LFT pathways and above the 0.6% average for all pathways combined. To note, there are a number of caveats to interpreting this percentage positive data which are set out in the main report.

Targeted testing: features of success & challenges - In May 2021 local partnerships were asked their views on features that supported and challenged targeted testing. Overall, partnerships reported data driven location of sites and communications and engagement as key elements of success for targeted testing, as well as flexible and responsive models of operation. Key challenges mirrored aspects of success and included issues around communications and engagement, and lack of flexible testing models. The issue of multiple testing pathways was also raised, mainly in relation to adding to general confusion. Partnerships made suggestions for improvements.

Public motivations and barriers – key ones are presented in the table, more are described in the main report. Partnerships described a range of strategies and actions to target motivations and address barriers.

Motivations: For reassurance

Barriers: Don't see the need

Motivations: To protect others

Barriers: Worry about the test itself

Motivations: To find out if they were positive because they had symptoms or had been in contact with a case or suspected case

Barriers: Financial concerns, eg as a result of not being able to work

Models of delivery and lessons learned - Four evolutions of targeted community testing models are apparent between 18 January and the end of May 2021. Models have also continued to evolve over time. Three specific examples are described: the 'Hub and Spoke' model; fixed rotating sites using Fire and Rescue Stations; and a 'Flying Squad' model, alongside aspects of operational learning.

Conclusion - From this evaluation evidence, the indications are that the targeted community testing programme up to the end of September 2021 has been effective at finding cases, including asymptomatic cases, and thus likely to have helped reduce transmission. In addition, the creation of additional capabilities around testing and the targeted nature of the programme - combining data-driven, flexible location of test sites, consideration of community characteristics and geography, and sustained communication and engagement is likely to have enhanced access to testing and encouraged certain groups to engage more with testing.