Experts said it meant the national statistics
, published daily on the government website and frequently referred to by ministers,
may far overstate the levels of pressures on the NHS.
The leaked data - covering all NHS trusts in England - show that, as of last Thursday,
just 44 per cent of patients classed as being hospitalised with Covid had tested positive by the time they were admitted. The majority of cases were not detected until patients underwent standard Covid tests, carried out on everyone admitted to hospital for any reason.
Overall, 56 per cent of Covid hospitalisations fell into this category, the data, seen by