BACKGROUND:The 2011 Pediatric Infectious Diseases Society/Infectious Diseases Society of America community-acquired pneumonia (CAP) guideline recommends narrow-spectrum antimicrobial therapy for most children hospitalized with CAP. However, few studies have assessed the effectiveness of this strategy.METHODS:Using data from 43 children’s hospitals, we conducted a retrospective cohort study to compare outcomes and resource utilization among children hospitalized with CAP between 2005 and 2011 receiving either parenteral ampicillin/penicillin (narrow spectrum) or ceftriaxone/cefotaxime (broad spectrum). Children with complex chronic conditions, interhospital transfers, recent hospitalization, or the occurrence of any of the following during the first 2 calendar days of hospitalization were excluded: pleural drainage procedure, admission to intensive care, mechanical ventilation, death, or hospital discharge.RESULTS:Overall, 13 954 children received broad-spectrum therapy (89.7%) and 1610 received narrow-spectrum therapy (10.3%). The median length of stay was 3 days (interquartile range 3–4) in the broad- and narrow-spectrum therapy groups (adjusted difference 0.12 days, 95% confidence interval [CI]: –0.02 to 0.26). One hundred fifty-six children (1.1%) receiving broad-spectrum therapy and 13 children (0.8%) receiving narrow-spectrum therapy were admitted to intensive care (adjusted odds ratio 0.85, 95% CI: 0.27 to 2.73). Readmission occurred for 321 children (2.3%) receiving broad-spectrum therapy and 39 children (2.4%) receiving narrow-spectrum therapy (adjusted odds ratio 0.85, 95% CI: 0.45 to 1.63). Median costs for the hospitalization were $3992 and $4375 (adjusted difference –$14.4, 95% CI: –177.1 to 148.3).CONCLUSIONS:Clinical outcomes and costs for children hospitalized with CAP are not different when treatment is with narrow- compared with broad-spectrum therapy.