Table 1. Characteristics of participating sites.
| Trust A | Trust B | Trust C | |
|---|---|---|---|
| Sampling time frame | July 2017-Aug 2018 | Jan 2019-Mar 2020 | Feb 2019-Oct 2019 |
| Median monthly acute medical admissions (IQR) | 5493 (5323–5643) | 3572 (3451–3728) | 2445 (2337–2541) |
| Median monthly total systemic antibiotic DDDs per acute medical admission (IQR)* | 1.65 (1.48–1.69) | 3.31 (3.08–3.66) | 0.48 (0.46–0.51) |
| Median monthly percent of antibiotics used in Access category (IQR) | 35.7% ( 34.7–36.7)% |
64.3% (62.9–65.2)% | 62.2% (57.7–68.8)% |
| Median monthly C. difficile colonisations (inclusive of infection)/100 acute medical admissions** | 0.50 (0.44–0.55) | 0.50 (0.44–0.54) | 0.34 (0.24–0.39) |
* DDDs are a World Health Organisation system for standardising antibiotic usage. 1 DDD reflects the average daily maintenance dose of an antibiotic when used in adults for its main indication. **. C. difficile colonisation defined as positive testing by PCR or Glutamate Dehydrogenase. Infection rates not shown because toxin test results defining of infection were not available for one site.