A new study published Online First in The Lancet shows that screening newborns for life-threatening congenital heart defects by using pulse oximetry is more accurate than other detection methods. Pulse oximetry is a simple, low-cost tests that measures oxygen levels and researchers suggest that the test should be adopted internationally as part of the routine assessment of all newborns. Lead author of the study, Shakila Thangaratinam from Queen Mary, University of London, explained: \"The findings of this meta-analysis provide compelling evidence for introduction of pulse oximetry as a screening method in clinical practice. The sensitivity of the test is higher than present strategies based on antenatal screening and clinical examination, and the false-positive rate is very low, especially when done after 24h of birth.\" Although congenital heart disease kills more infants than any other birth defect, the researchers highlight that these outcomes can be improved if defects are detected early. The potential of pulse oximetry to identify significant or life-threatening heart defects in infants has been reported in earlier studies, although researchers are still unsure about the accuracy of the test and the false-positive rates. At present, pulse oximetry screening is only performed in the United States. As a result, the team set out to evaluate the test\'s ability to detect congenital heart disease by examining 13 studies including data for almost 230,000 newborn babies. The researchers found that the test had high specificity (99.9%) with moderate sensitivity, identified 76.5% cases of congenital heart defects, and had a low false positive rate (0.14%). According to the researchers, when the test was done after 24h, the false-positive rate was considerably lower (0.05%) than when it was done before 24h (0.50%). They explain: \"This finding needs to be balanced against the increasing tendency of many countries to discharge babies earlier than 24 hours and the risk of babies with serious conditions deteriorating before screening has taken place. In view of the many babies that have now been tested with pulse oximetry, further research in this area is unlikely to produce substantially different findings.\" The researchers conclude: \"Strong evidence exists for health-care systems to consider introduction of pulse oximetry as a screening test for critical congenital heart defects in asymptomatic newborn babies.\" In an linked comment, Alex Kemper from Duke University and Gerard Martin from George Washington University School of Medicine in the USA, say: \"Guaranteeing follow-up after a positive screen will be the biggest barrier to adoption of screening. Many hospitals do not have access to pediatric echo-cardiography, which is needed for newborn babies with a positive screen not attributable to another cause. The debate about the relative benefit of screening as part of a public health mandate such as newborn screening compared to incorporation into usual care will depend on the ongoing work to assess how screening is adopted and the impact of screening on long-term outcomes.\"