How reliable are rapid antigen tests in detecting COVID?
RATs accuracy tested in primary-care settings
A systematic review and meta-analysis published in JBI Evidence Synthesis aimed to assess the diagnostic accuracy of rapid antigen tests (RATs) used in primary-care settings compared to the gold standard real-time reverse transcriptase polymerase chain reaction (RT-PCR) test for diagnosing SARS-CoV-2 infection in adults.
Real-time RT-PCR is the accepted gold standard for diagnostic testing, requiring technical expertise and expensive equipment that are unavailable in most primary care locations. RATs are less expensive and require less expertise.
Based on the meta-analysis, Roche’s SARS-CoV-2 Rapid Antigen Test and Abbott’s BinaxNOW tests meet the WHO’s recommendation of minimum diagnostic accuracy for symptomatic individuals (≥ 80% sensitivity and ≥ 97% specificity). The summary of findings states:
These tests can be reliably used in primary care settings, with the understanding that negative results need to be confirmed through RT-PCR or repeated testing over several days when COVID-19 is highly suspected. These tests are widely available, relatively inexpensive, and have good reliability.
The systematic review and meta-analysis finds that overall, RATs are excellent at predicting when a positive result means a positive diagnosis of COVID-19. However, these tests have reduced capacity to allow a negative result to rule out COVID-19 as a diagnosis.
In the primary care setting, false-negative results should be considered for further testing via RT-PCR or repeat RATs over several days when there is high suspicion of COVID-19, such as loss of taste or smell as a presenting symptom. Overall negative likelihood ratio is dependent on local prevalence, and health care practitioners should take into account their current community status when determining the best course of action for a negative RAT result.
Read more in Comparison of diagnostic accuracy of rapid antigen tests for COVID-19 compared to the viral genetic test in adults: a systematic review and meta-analysis.
Hirabayashi, Ellyn; Mercado, Guadalupe; Hull, Brandi; Soin, Sabrina; Koshy-Chenthittayil, Sherli; Raman, Sarina; Huang, Timothy; Keerthisinghe, Chathushya; Feliciano, Shelby; Dongo, Andrew; Kal, James; Azizan, Azliyati; Duus, Karen; Else, Terry; DeArmond, Megan; Stone, Amy E.L.
JBI Evidence Synthesis 22(10):p 1939-2002, October 2024. | DOI: 10.11124/JBIES-23-00291