Antibiotic use for FN
Antibiotic use on day one of FN before and after PHIG intervention is shown in Table 4 . Major differences in practice existed between different PHO units prior to intervention. In units 1 and 2, triple antibiotic therapy (i.e., an antipseudomonal beta-lactam, a second Gram negative agent and a Gram-positive agent) was commonly practiced; in the BMT unit monotherapy with an antipseudomonal beta-lactam was more commonly used; in unit 5, double Gram-negative coverage was used; and in unit 6, triple antibiotic therapy and other non-standard regimens were frequently used. Significant improvements in appropriateness of antibiotic prescribing were noted after the intervention (p =0.005). For all units combined, antibiotic therapy was started without obtaining cultures less frequently after the intervention (9.8% versus 14.1% before, p =0.006). This practice was more frequent in PHO units located in general compared to pediatric hospitals before (25.5% compared to 9%) and after intervention (18.2% compared to 5.8%), and this difference was highly significant (p =0.001 for both comparisons).