Table 3 Risk factors predictive of **C. difficile** infection. **Risk factor** | **Odds ratio (95% CI)** | *P* value |

Antibiotics | 3.35 (2.78–4.03) | 6.2 × 10^{−37} |

Immunosuppression | 2.47 (2.06–2.96) | 8.4 × 10^{−23} |

Recent hospitalization | 3.32 (2.72–4.06) | 1.8 × 10^{−31} |

Current hospitalization | 2.94 (2.40–3.61) | 8.4 × 10^{−25} |

Prior CDI | 5.84 (4.42–7.72) | 1.6 × 10^{−35} |

Any one risk factor | 1.16 (0.74–1.83) | 0.51 |

Any two risk factors | 3.89 (2.76–5.48) | 7.4 × 10^{−15} |

Any three risk factors | 5.00 (3.59–6.96) | 1.2 × 10^{−21} |

Any four risk factors | 9.28 (6.67–12.91) | 5.4 × 10^{−40} |

All five risk factors | 24.24 (12.96–45.32) | 1.8 × 10^{−23} |