A comprehensive Cochrane review of 21 studies, including over 13 million participants, assessed the effectiveness of various SARS-CoV-2 testing strategies for reducing COVID-19 transmission, hospitalisations, and deaths in symptomatic and asymptomatic individuals. Across multiple testing approaches—including RT-PCR, antigen-detecting rapid tests, home-based testing, and repeated screening—only one observational study reported critical outcomes, showing very uncertain effects on reducing hospitalisation and mortality. The study comparing weekly RT-PCR testing with no testing indicated a slight decline in hospitalisation and a 33.8% decrease in expected mortality, but the evidence was downgraded to very low certainty due to methodological limitations and imprecision.
Overall, no included studies assessed whether testing strategies reduced new COVID-19 cases or prevented serious adverse events related to testing procedures. Evidence gaps were also notable for comparisons between antigen-detecting rapid tests and NAAT-based testing, limiting interpretation of benefits and harms. The findings reflect substantial uncertainty regarding the real-world impact of testing strategies on major health outcomes, underscoring the need for future high-quality studies with standardised outcome reporting to guide policy and practice.
Keywords: COVID-19 testing, SARS-CoV-2 screening, RT-PCR, public health strategies