Results: Compared with the preintervention period, the change in the slope of the total use of antibiotics
was −8.71 defined daily dose (DDD) per 1,000 patient days per month (95% confidence interval [CI],
−11.43 to −5.98; P < .01) in the SPAs monitoring period and −1.95 DDD per 1,000 patient days per month
(95% CI, −2.93 to −0.96; P < .01) in the CDSS period. Use of third-generation cephalosporins and
aminoglycosides showed change comparable with that of total antibiotics use, but use of vancomycin and
carbapenem was unchanged in the CDSS period. Trends of the proportions of extended-spectrum
β-lactamase–producing Escherichia coli, meropenem-resistant Pseudomonas aeruginosa, and methicillinresistant
Staphylococcus aureus have been reversed or decreased in slope in the CDSS period. Length of
hospital stay also showed a negative change in slope in the CDSS period.