Cochrane Infectious Diseases Group (https://cidg.cochrane.org/background)
Cochrane Netherlands (https://netherlands.cochrane.org/over-ons)
Universities of Amsterdam, Utrecht, Leuven and Ottawa
WHO (https://www.who.int/ )
- Deeks JJ, Dinnes J, Takwoingi Y, et al. Antibody tests for identification of current and past infection with SARS-CoV-2. Cochrane Database Syst Rev2020;6:Cd013652. doi: 10.1002/14651858.Cd013652
Serology tests to detect the presence of antibodies to SARS-CoV-2 aim to identify previous SARS-CoV-2 infection, and may help to confirm the presence of current infection. We included 54 studies with 15,976 samples, of which 8,526 were from cases of SARS-CoV-2 infection, and provided data for 25 commercial laboratory-based tests or lateral flow assays and numerous in-house assays. The sensitivity of antibody tests is too low in the first week since symptom onset to have a primary role for the diagnosis of COVID-19, but they may still have a role complementing other testing in individuals presenting later, when RT-PCR tests are negative, or are not done. Antibody tests are likely to have a useful role for detecting previous SARS-CoV-2 infection if used 15 or more days after the onset of symptoms. The duration of antibody rises is currently unknown, and we found very little data beyond 35 days post-symptom onset. We are therefore uncertain about the utility of these tests for seroprevalence surveys for public health management purposes. Concerns about high risk of bias and applicability of results make it likely that the accuracy of tests when used in clinical care will be lower than reported in the included studies.
- Struyf T, Deeks JJ, Dinnes J, et al. Signs and symptoms to determine if a patient presenting in primary care or hospital outpatient settings has COVID-19 disease. Cochrane Database of Systematic Reviews 2020;6 doi: 10.1002/14651858.CD013665
Symptoms such as fever or cough, and signs such as oxygen saturation or lung auscultation findings, are the first and most readily available diagnostic information that could be useful to either rule out COVID-19 disease, or select patients for further diagnostic testing. We identified 16 studies including 7706 participants, providing data on 27 signs and symptoms (systemic, respiratory, gastrointestinal and cardiovascular). The individual signs and symptoms appear to have very poor diagnostic properties, although this should be interpreted in the context of selection bias and heterogeneity between studies. Based on currently available data, neither absence nor presence of signs or symptoms are accurate enough to rule in or rule out disease.
- Dinnes J, Deeks JJ, Adriano A, et al. Rapid point-of-care antigen and molecular-based tests for the diagnosis of SARS-Cov-2 infection. Cochrane Database of Systematic Reviews 2020, Issue 8. Art. No.: CD013705. doi: 10.1002/14651858.CD013705.
Point-of-care antigen and molecular tests to detect current SARS-CoV-2 infection have the potential to allow earlier detection and isolation of confirmed cases compared to laboratory-based diagnostic methods, with the aim of reducing household and community transmission. We included 18 studies with 3,198 unique samples, of which 1,775 had confirmed SARS-CoV-2 infection, and provided data for 8 commercial tests (4 antigen and 4 molecular) and one in-house antigen test. These early stage evaluations of point-of-care tests were largely based on laboratory samples. The findings have limited applicability, and we cannot be sure whether tests will perform in the same way in clinical practice, and according to symptoms of COVID-19, duration of symptoms, or in asymptomatic people. Rapid tests have the potential to be used to inform triage of RT-PCR use, allowing earlier detection of those testing positive, but the evidence currently is not strong enough to recommend their use in clinical practice.
- Salameh J-P, Leeflang MMG, Hooft L, et al. Thoracic imaging tests for the diagnosis of COVID-19. Cochrane Database of Systematic Reviews. IN press
This review examined the evidence for chest imaging (computed tomography (CT), X-ray and ultrasound) in the evaluation of people suspected to have COVID-19. A total of 84 studies have been included: 71 ‘cases-only’ studies with 6331 participants diagnosed with COVID-19 at the time of recruitment, and 13 studies allowing both sensitivity and specificity to be estimated, 10 studies with 1399 participants suspected of COVID-19 and three case-control studies with 549 cases and controls. The significant uncertainty resulting from poor study quality and heterogeneity of included studies limited ability to confidently draw conclusions based on our results. The review findings suggest that chest CT is sensitive but not specific for the diagnosis of COVID-19 in suspected patients. This low specificity could also be the result of the poor sensitivity of the reference standard (RT-PCR), as CT could potentially be more sensitive than RT-PCR in some cases. Because of limited data, limited data, accuracy estimates of chest X-ray and ultrasound of the lungs for the diagnosis of COVID-19 should be carefully interpreted.
- Stegeman I, Ochodo EA, Guleid F, et al. Routine laboratory testing to determine if a patient has COVID-19 pneumonia or SARS-COV-2 infection. Cochrane Database of Systematic Reviews.
Routine laboratory markers commonly used to assess the health status of a patient are also used in patients with COVID-19 infection and may be useful for triage of people with potential COVID-19 infection for the necessity of treatment or more intensive treatment, especially in situations where time and resources are limited. A total of 21 studies were included in this review, reporting data for 67 different laboratory tests in 70,711 patients, of whom 14,126 had COVID-19. There was considerable heterogeneity in tests, cut offs and settings. The accuracy of 16 tests were summarised using meta-analysis, of which only three performed at sensitivity-specificity combinations where both sensitivity and specificity were above 50%. There was low to very low certainty in the summary estimates of the tests. Evidence to date suggests that in sick hospitalised patients, routine tests cannot discriminate between COVID-19 and other diseases as the cause of infection, inflammation or tissue damage and should preferably not be used as standalone tests for COVID-19.
Reviews in preparation:
- Cochrane COVID–19 Diagnostic Test Accuracy Group. The effect of sample site and collection procedure on identification of SARS-CoV-2 infection using laboratory based molecular tests. Cochrane Database of Systematic Reviews in preparation
This review will include within-study (direct) comparisons of the diagnostic yield of laboratory-based molecular tests according to sample site (including saliva, upper or lower respiratory tract samples, faeces or urine) or collection procedure (including swab versus wash, different storage media, and self sampling compared to health care provider sampling) in the same patients.
- Cochrane COVID–19 Diagnostic Test Accuracy Group. PCR compared to alternative laboratory-based molecular tests for identification of SARS-CoV-2 infection. Cochrane Database of Systematic Reviews in preparation
This review will include within-study (direct) comparisons of the diagnostic yield of different laboratory-based molecular tests, including those using alternative methods for extraction of RNA using the same test), and comparisons between RT-PCR and innovative NAA technologies such as RT-LAMP or CRISPr.
Other Covid-19 related output:
- Taylor-Phillips S, Berhane S, Sitch AJ et al. Information given by websites selling home self-sampling COVID-19 tests: An analysis of accuracy and completeness. This review of websites selling COVID-19 tests in the UK and US reports on accuracy and completeness of communication prior to purchase. Three key topics for communication are covered: who should take the test ad when; test accuracy; and interpreting test results. medRxiv 2020.08.18.20177360; doi: https://doi.org/10.1101/2020.08.18.20177360
- Raffle AE and Taylor–Phillips S. Test, Test, Test: Lessons learned from experience with mass screening programmes. A report written for Independent Sage, summarising implications for best practice when evaluating tests in public settings. Advice note for Independent Sage 5 June 2020:
- Deeks JJ, Brookes AJ, Pollock AM. Operation Moonshot proposals are scientifically unsound BMJ 2020; 370 :m3699.
- Watson J, Richter A, Deeks JJ. Testing for SARS-CoV-2 antibodies BMJ 2020; 370 :m3325.