Influence of symptom duration and WBC profile on the negative predictive value of a nondiagnostic ultrasound in children with suspected appendicitis

Retrospective study of 2,277 pediatric patients evaluates how symptom duration and WBC profiles improve the negative predictive value of nondiagnostic ultrasounds in suspected appendicitis. Findings show NPV increases from 83.7% at ≤24 hours to 94.5% at >72 hours, with normal WBC profiles further enhancing diagnostic confidence.