The Research Question

1. The Research Question Systematic review of the diagnostic accuracy of capillary refill time for serious illness in children • S Fleming, P Gill, C Jones, A Van den Bruel, J Taylor, C Heneghan, M Thompson • How good is capillary refill time (CRT) as a diagnostic indicator of serious illness in children? • Why this is important? • Simple and quick test requiring no equipment • Easily performed on every child • Widely recommended, but no existing systematic review

2. What the Researchers Did • Design: Systematic review of diagnostic accuracy • 3 databases, not restricted by language or geography • Inclusion Criteria • CRT measured on at least 20 children (<18 years) • Relationship between CRT and relevant clinical outcome • Quality assessment using criteria based on QUADAS-2 checklist • Search strategyidentified 23 relevant papers • 9 papers on mortality • 6 papers on dehydration • 10 papers on other serious outcomes

3. What the Researchers Found • Mortality • CRT is highly specific, but has low sensitivity • Specificity 92.3% (95%CI 88.6 to 94.8%) • Data predominantly from low income settings • Dehydration and other serious outcomes • Prolonged CRT consistently increases the post-test probability of serious outcomes • Normal CRT does not noticeably reduce the probability of adverse outcomes

4. What This Means for Clinical Practice • CRT has value as a “red flag” for a wide variety of serious illnesses in children • In low-income settings, there is evidence for CRT as a “red-flag” for risk of mortality • Clinicians treating children with prolonged (≥3s) CRT should consider the possibility of serious illness