Sample size calculations based on previously published studies
| Definition of AAD | Control event rate (%) | Experimental event rate (%) | Sample size | Sample size including 20% lost to follow-up |
|---|---|---|---|---|
| ≥3 loose or watery stools per day for a minimum of 48 hours during antibiotic treatment18 | 23 | 8 | 104+104 | 250 |
| ≥3 loose or watery stools per day for a minimum of 24 hours during antibiotic treatment22 | 28.3 | 11.8 | 104+104 | 250 |
| ≥2 loose or watery stools per day for a minimum of 24 hours during antibiotic treatment20 | 26 | 8 | 79+79 | 190 |
AAD, antibiotic-associated diarrhoea.