TABLE 3.
Risk ratio (RR) analysis of the probability of a cryptosporidiosis outbreak among veterinary students, depending on the fecal Cryptosporidium load of the calves used for fetotomy exercisesa
| Fecal Cryptosporidium load category | No. of calves | No. of calves used on an outbreak day | Proportion of calves used on an outbreak day (%) | RR | 95% CI | P value |
|---|---|---|---|---|---|---|
| +++ (CT < 23.8) | 13 | 7 | 53.85 | 5.38 | 1.87–15.50 | 0.002 |
| ++ (CT 23.8–35.0) | 27 | 8 | 29.63 | 2.96 | 0.99–8.87 | 0.054 |
| + (CT > 35.0) | 13 | 1 | 7.69 | 0.77 | 0.09–6.28 | 1.000 |
| Negative | 40 | 4 | 10 | Ref. | Ref. | Ref. |
a
Ref., reference value; RR, risk ratio; CI, confidence interval.