**Results:** There were 347 patients with an SAH of whom 260 were aneurysmal SAH. MSCT identified 253 (97.3%) of all aneurysmal SAH and 332 (95.7%) of all SAH. The sensitivity of MSCT was 99.6% (95% CI 97.6 to 100) for aneurysmal SAH and 99.0% (95% CI 97.1 to 99.8) for all SAH at 48 hours after headache onset. At 24 hours after headache onset, the sensitivity for aneurysmal SAH was 100% (95% CI 98.3 to 100). **Conclusion:** These data suggest that it may be possible to extend the timeframe from headache onset within which modern MSCT can be used to rule out aneurysmal SAH. Source: Vincent A, Pearson S, Pickering JW, Weaver J, Toney L, Hamill L, Hurrell M, Than M. Sensitivity of modern multislice CT for subarachnoid haemorrhage at incremental timepoints after headache onset: a 10-year analysis. Emerg Med J. 2021 Nov 24:emermed-2020-211068. doi: 10.1136/emermed-2020-211068. Epub ahead of print. PMID: 34819306.