Evidence map›Paper›PMID 37611000›Full record

ArticlePloS one2023

Test performance of lateral flow rapid antigen tests for COVID-19 in Welsh adult care home staff using routine surveillance data.

Craig Hogg, Sian Boots, Daniel Howorth, Christopher Williams, Margaret Heginbothom, Jane Salmon, Robin Howe

Open access · goldAbstract read
In one paragraph

Article in PloS one, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
1.7field-weighted citation impact, top 16% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 9 citations in OpenAlex.

  1. Article
  2. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 1 institution in 1 country.

Craig HoggCommunicable Disease Surveillance Centre, Public Health Wales, Cardiff, Wales, United Kingdom.ORCID 0000-0002-0376-0377
Sian BootsCommunicable Disease Surveillance Centre, Public Health Wales, Cardiff, Wales, United Kingdom.
Daniel HoworthCommunicable Disease Surveillance Centre, Public Health Wales, Cardiff, Wales, United Kingdom.
Christopher WilliamsCommunicable Disease Surveillance Centre, Public Health Wales, Cardiff, Wales, United Kingdom.
Margaret HeginbothomCommunicable Disease Surveillance Centre, Public Health Wales, Cardiff, Wales, United Kingdom.
Jane SalmonCommunicable Disease Surveillance Centre, Public Health Wales, Cardiff, Wales, United Kingdom.
Robin HowePublic Health Wales Microbiology, Cardiff, Wales, United Kingdom.
Public Health Wales · GB

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundLateral flow tests (LFTs) have been used to screen for SARS-CoV2 in Wales since January 2021. Between May and August 2021, adult care home staff policy was for biweekly Innova LFT and weekly Polymerase Chain Reaction (PCR) testing while asymptomatic. We estimated test performance of LFTs conducted in adult care home staff using PCR tests as a reference standard.

methodsTest results from surveillance data were matched by individual where both LFT and PCR were taken on the same day. We calculated sensitivity, specificity, positive and negative predictive values, and agreement using Matthew's correlation coefficient. Ct values of positive PCR results were compared by matched LFT result. Analysis was conducted using R v4.1.3.

resultsWe analysed 115,593 test pairs, 499 (0.43%) of which were PCR positive. Median age was 48 (IQR: 22) and 85.00% of the study population were female. Test result agreement was 99.59% (95%CI 99.55-99.63; MCC: 0.38, p<0.001). Sensitivity and specificity were 25.65% (95%CI 22.02-29.67) and 99.91% (95%CI 99.89-99.93), respectively. PPV was 55.90% (95%CI 49.42-62.17) and NPV was 99.68% (95%CI 99.64-99.71). Crude Ct values were significantly lower in positive PCR tests matched to a positive LFT compared to a negative LFT.

conclusionsSpecificity and negative predictive value were high in an asymptomatic population of care home staff indicating this test is an effective tool for identifying cases of SARS-CoV-2 infection during periods of high prevalence where transmission is likely, due to the presence of high viral loads. Positive predictive value results are lower than existing literature yet should be considered in light of the asymptomatic study population and low prevalence (under 1%) at the time most of these tests were conducted. Performance improved at times of higher prevalence during the study. These results suggest that whilst lateral flow tests are effective for identifying SARS-COV-2 infections with high viral loads, they are not effective at identifying cases with a low viral load. When an LFT provides a negative result, false negatives should be considered and additional diagnostic tests performed.

Indexed as

COVID-19RNA, ViralAdultCOVID-19 TestingEthnicityFemaleHumansImmunologic TestsMaleMiddle AgedSARS-CoV-2RNA, Viral

Identifiers

PMID37611000
PMCPMC10446167
OpenAlexW4386090826

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.