In a systematic review, researchers assessed the diagnostic value of certain physical symptoms that children may display that could indicate a urinary tract infection. The team performed literature reviews of the most prominent medical research databases from inception until Jan. 20, 2020 for studies reporting specific diagnostic accuracy data for clinical signs and symptoms compared to the use of urine cultures in children 18 and younger. For each clinical feature, the team calculated the likelihood ratios and predictive values for UTI. Researchers conducted several analyses to do this. Of the almost 11,000 studies they accessed, 35 studies of moderate to high quality were included and provided information on 58 clinical symptoms and six prediction rules. They found that only circumcision, diaper rash and stridor (a high-pitched vibrating, breathing sound in the throat, caused by a possible airway obstruction) are useful for ruling out UTI and that body temperature or fever duration have limited diagnostic value. Presence of cloudy urine, malodorous urine, hematuria, no fluid intake, suprapubic tenderness, and loin tenderness increase the probability of UTI. The authors advise that physicians should not restrict urine sampling to children with unexplained fever or specific features suggestive of a urinary tract infection.