Interrater reliability of pediatric point-of-care lung ultrasound findings

Objective We sought to assess interrater reliability (IRR) of lung point-of-care ultrasound (POCUS) findings among pediatric patients with suspected pneumonia. Methods A convenience sample of patients between the ages of 6 months and 18 years with a clinical suspicion of pneumonia had a lung ultrasound performed by a POCUS-credentialed emergency medicine physician with subsequent expert review. Each lung zone was assessed as either normal or abnormal, and specific ultrasound findings were recorded. IRR was assessed by intraclass correlation coefficient (ICC) and kappa statistics. Results Seventy-one patients, with a total of 852 lung zones imaged, were included. The sonographer assessment of normal versus abnormal, across each of the zones, demonstrated moderate agreement with ICC 0.46 (95% CI: 0.41, 0.52) and kappa 0.56. Right-sided zones demonstrated moderate agreement [0.43 (CI 0.35, 0.51)] while left-sided zones, specifically left-sided anterior zones, showed only fair agreement [0.36 (0.28, 0.44)]. IRR varied between specific findings: ICC for B-lines 0.52 (95% CI: 0.46, 0.57), pleural effusion 0.40 (0.34, 0.45), consolidation 0.39 (0.33, 0.44), subpleural consolidation 0.31 (0.25, 0.37), and pleural line irregularity 0.16 (0.10, 0.23). A composite indicator of typical pneumonia findings (consolidation, B-lines, and pleural effusion) demonstrated moderate [ICC 0.52 (0.46, 0.57)] reliability. Conclusions We found moderate interrater reliability of lung POCUS findings for the assessment of pediatric patients with suspected pneumonia. B-lines had the highest reliability. Further assessment of lung POCUS is necessary to guide proper training and optimal scanning techniques to ensure adequate reliability of ultrasound findings in the assessment of pediatric pneumonia.