FIGURE 1.

Impact of national guidelines on prescribing of third-generation cephalosporins (A) and penicillin/ampicillin (B) for pediatric CAP, January 2010 to June 2012. Seasonally adjusted estimates of third-generation cephalosporin (A, green) and penicillin/ampicillin (B, blue) use among children hospitalized with CAP at 3 US children’s hospitals before and after the release of national guidelines; the vertical dashed line indicates the month the guidelines were first released (August 30, 2011); the pre- and postguideline periods included January 2010 to August 2011 and October 2011 to June 2012, respectively; absolute difference (%) was calculated by comparing the observed antibiotic prescribing patterns by the end of the study period (estimated from the postguideline regression model) with the expected antibiotic prescribing by the end of the study period had the guideline not been released (estimated from the preguideline trend).