Knowledge barriers in a national symptomatic-COVID-19 testing programme

PLOS Glob Public Health. 2022 Jan 19;2(1):e0000028. doi: 10.1371/journal.pgph.0000028. eCollection 2022.


Symptomatic testing programmes are crucial to the COVID-19 pandemic response. We sought to examine United Kingdom (UK) testing rates amongst individuals with test-qualifying symptoms, and factors associated with not testing. We analysed a cohort of untested symptomatic app users (N = 1,237), nested in the Zoe COVID Symptom Study (Zoe, N = 4,394,948); and symptomatic respondents who wanted, but did not have a test (N = 1,956), drawn from a University of Maryland survey administered to Facebook users (The Global COVID-19 Trends and Impact Survey [CTIS], N = 775,746). The proportion tested among individuals with incident test-qualifying symptoms rose from ~20% to ~75% from April to December 2020 in Zoe. Testing was lower with one vs more symptoms (72.9% vs 84.6% p<0.001), or short vs long symptom duration (69.9% vs 85.4% p<0.001). 40.4% of survey respondents did not identify all three test-qualifying symptoms. Symptom identification decreased for every decade older (OR = 0.908 [95% CI 0.883-0.933]). Amongst symptomatic UMD-CTIS respondents who wanted but did not have a test, not knowing where to go was the most cited factor (32.4%); this increased for each decade older (OR = 1.207 [1.129-1.292]) and for every 4-years fewer in education (OR = 0.685 [0.599-0.783]). Despite current UK messaging on COVID-19 testing, there is a knowledge gap about when and where to test, and this may be contributing to the ~25% testing gap. Risk factors, including older age and less education, highlight potential opportunities to tailor public health messages. The testing gap may be ever larger in countries that do not have extensive, free testing, as the UK does.

Grants and funding

ZOE Global provided in-kind support for all aspects of building, running, and supporting the app and service to all users worldwide. CMA and JSB: Facebook Sponsored Research Agreement [INB1116217]. CHS Alzheimer’s Society Junior Fellowship [AS-JF-17-011]. The Department of Twin Research & Genetic Epidemiology at King’s College London receives grant support from the Wellcome Trust (212904/Z/18/Z), the MRC British Heart Foundation Ancestry and Biological Informative Markers for Stratification of Hypertension (AIMHY; MR/M016560/1), the European Union, CDRF, ZOE Global, NIH, the National Institute for Health Research (NIHR)-funded BioResource, and Clinical Research Facility and Biomedical Research Centre based at Guy’s and St Thomas’ National Health Service (NHS) Foundation Trust, in partnership with King’s College London. SO is funded by the Wellcome Engineering and Physical Sciences Research Council (EPSRC) Centre for Medical Engineering (WT203148/Z/16/Z) and the Wellcome Flagship Programme (WT213038/Z/18/Z). The School of Biomedical Engineering & Imaging Sciences is supported by the Wellcome EPSRC Centre for Medical Engineering at King’s College London (WT203148/Z/16/Z) and the Department of Health via the NIHR comprehensive Biomedical Research Centre award to Guy’s and St Thomas’ NHS Foundation Trust, in partnership with King’s College London and King’s College Hospital NHS Foundation Trust. EM is funded by a Medical Research Council UK Skills Development Fellowship. ATC was supported in this work through a Stuart and Suzanne Steele MGH Research Scholar Award. The Massachusetts Consortium on Pathogen Readiness (MassCPR) and Mark and Lisa Schwartz supported MGH investigators (DAD, LHN, ATC). The funding sources played no role in the study design, collection, analysis, interpretation, writing or decision to submit the paper for publication.