Reliability of Physical Examination Findings in Youths Diagnosed With Pneumonia

Importance: Community-acquired pneumonia (CAP) accounts for nearly 2 million pediatric outpatient and 375 000 emergency department (ED) visits annually in the US. Guidelines recommend relying on physical examination findings, not imaging, to diagnose CAP in youths who can be treated as outpatients. Objective: To determine the interrater reliability (IRR) of physical examination findings in youths diagnosed with CAP in EDs. Design, Setting, and Participants: This was a planned analysis from an ongoing prospective cohort study (pediatric CAP severity [PedCAPS]). Youths aged 3 months to 17 years with CAP were recruited at 7 academic pediatric EDs within the US from August 1, 2023, until May 24, 2025; participants had signs of lower respiratory tract infections, fever within 48 hours, and pneumonia on chest radiography, if performed. Youths with chronic pulmonary diseases (except asthma), sickle cell disease, immunodeficiency, cardiac disease, neurological disorders affecting respiration, and aspiration pneumonia were excluded, as were those hospitalized within the preceding 30 days or transferred from other EDs or hospitals. Main Outcomes and Measures: Two examiners evaluated the same patient within 60 minutes of each other and independently recorded their findings. IRR of physical examination findings was reported by raw agreement and Fleiss κ. A lower bound of the 95% CI of 0.4 for κ was considered acceptable reliability. Results: Among 252 youths with paired physical examinations (median [IQR] age, 5.7 [3.4-8.8] years; 127 female [50.4%]), the most frequent comorbidity was asthma (56 youths [22.2%]). In the overall study population, no physical examination finding met predefined significance for IRR. Wheezing (κ = 0.50; 95% CI, 0.39-0.62) and retractions (κ = 0.49; 95% CI, 0.37-0.60) had the highest IRR. In subanalyses of 124 youths discharged home and 128 youths who were hospitalized, IRRs of physical examinations were similar between the 2 groups. Conclusions and Relevance: In this study, individual auscultation findings, such as decreased breath sounds, crackles, or rhonchi, did not demonstrate sufficient reliability to be used alone for diagnosis.