Antibiotic Stewardship Measurement Guidelines

Primary Measurement Method

The Centers for Disease Control and Prevention recommends measuring antibiotic use using Days of Therapy (DOTs) as the preferred metric, with measurements stratified by individual antibiotic agent and normalized to patient census 1, 2
DOTs are unaffected by dose adjustments, making them more accurate than Defined Daily Doses (DDDs) for tracking actual antibiotic exposure 2
DOTs can be applied to both adult and pediatric populations, whereas DDDs have significant limitations in pediatrics due to weight-based dosing 2
The CDC's National Healthcare Safety Network requires DOT reporting through the Antimicrobial Use and Resistance Module, making this the standardized national metric 1, 2

Every antibiotic stewardship program must measure antibiotic use stratified by individual antibiotic agent, with normalization to patient census (e.g., DOTs per 1000 patient-days) to allow meaningful comparisons over time and between facilities 1, 2, 3, 4
The counting system should include stratification by specific antibiotics rather than just total antibiotic use, and unit-level, provider-level, or service-level breakdowns to identify targeted intervention opportunities 1, 2, 4

Measuring antibiotic appropriateness through guideline compliance is equally important as counting volume, and stewardship programs should assess compliance with facility-specific or national treatment guidelines 1, 3, 4
Stewardship programs should share appropriateness data with clinicians to inform prescribing practices, and monitor the "5 Ds of stewardship": right diagnosis, drug, dose, duration, and de-escalation 1, 4

Antibiotic costs should be measured based on prescriptions or administrations rather than purchasing data, and should be normalized to patient-days (e.g., antibiotic cost per patient-day) 2
The cost measurement approach should reflect actual patient-level use rather than pharmacy inventory changes, and must account for program costs including stewardship personnel salaries 2

C. difficile infection rates have significant limitations as stewardship metrics because they are affected by infection control practices and other confounding factors, but may be useful for targeted interventions 1, 2
Antibiotic resistance patterns are complex and influenced by multiple variables beyond antibiotic use alone, but may be useful for targeted interventions 1, 2