COVID-19-related hospitalisation

Method

Admission to hospital with COVID-19 recorded as the reason for admission, within a stated observation window after infection or randomisation, pooled as a risk ratio or odds ratio. The window length is recorded on the edge and is not optional — short-term and long-term windows give materially different estimates from the same cohorts.

The method is part of the endpoint identity. Studies measuring the same quantity by a different method are held as separate endpoints.

Notes

Confused with the composite of 'hospitalisation and/or death', which reviews report alongside it from the same patients and which yields a different estimate (0.43 against 0.52 in one review); recording both as independent endpoints double-counts the same admissions and dilutes the hospitalisation signal. Also distinct from progression to severe COVID-19 disease, a clinical-severity classification that does not require an admission and is sensitive to local admission thresholds, and from ICU admission, a strictly narrower event.