Cases (n = 587) | Controls (n = 1460) | p Value | |
---|---|---|---|

n (%) | n (%) | ||

p values derived by χ^{2} tests for categorical variables and by the Kruskal-Wallis test for comparison of continuous variables. | |||

Age (y) | |||

0–20 | 79 (13) | 76 (5) | <0.001 |

20–40 | 207 (35) | 569 (39) | |

40–60 | 156 (27) | 445 (30) | |

60–80 | 145 (25) | 370 (25) | |

Median | 41.64 | 43.76 | 0.003 |

Sex | |||

Male | 253 (43) | 642 (44) | 0.7 |

Female | 334 (57) | 818 (56) | |

Date of entry to study | |||

Median | 1/10/90 | 1/03/90 | <0.001 |

Range | 1/06/87–23/08/93 | 1/06/87–8/10/93 | |

Smoking | |||

Smoker | 165 (28) | 297 (20) | 0.001 |

Non-smoker | 291 (50) | 796 (55) | |

Unknown | 131 (22) | 367 (25) | |

Antibiotic courses | |||

At least one | 418 (71) | 843 (58) | <0.001 |

Median | 2 | 1 | <0.001 |