Pre-test probability of meningitis in children with acute illness (%) | Clinical examination finding | Post-test probability of meningitis (%) | |

Absent | Nuchal rigidity | 0.200 | |

Kernig’s sign | 0.200 | ||

Brudzinski’s sign | 0.170 | ||

0.308 | Present | Nuchal rigidity | 0.640 |

Kernig’s sign | 0.609 | ||

Brudzinski’s sign | 0.527 |

A summary of pretest and post-test probability of meningitis (bacterial and viral) according to clinical examination findings.

Pretest probability derived from ref 3. Post-test probabilities calculated using likelihood ratios from ref 2.