Death rates in a Welsh village misconstrued

Readers of The Daily Telegraph and the Western Mail may well have suffered a tea-spilling moment over their breakfast when these two papers reported [7] that death rates in Bryncethin ward, in Bridgend, were higher than in Rwanda.

Can this be true? To be fair, both papers appeared to have some doubts, though that didn’t prevent the Western Mail from publishing a sidebar reporting local residents as expressing little surprise at the news. A barman was quoted as saying: “We have a lot of deaths round here, a lot of funerals and wakes ... we used to have a full bar but it’s nowhere near as busy these days.”

My thanks to Myer Glickman, head of health analysis at the ONS, for clarifying this. In addition to random variations which affect death registrations in such a small area as Bryncethin (population 1,276) there is another reason why the comparison with Rwanda is false. He explains in a letter to the Western Mail (12 January) that death rates as published are standardised by the age structure of the population.

UK data is standardised by reference to the UK population, which is relatively old. But the WHO, from which the Rwanda data came, standardises by reference to a much younger population. Bryncethin’s death rate of 1,499 per 100,000 based on the ONS standardisation would be only 1,048 per 100,000 using the WHO method – lower than Rwanda’s, which WHO records as 1,452 per 100,000.

It’s still pretty high, but figures for such a small area vary widely by chance, and may be affected by the presence of a nursing home or hospice. They are published with wide confidence intervals – in the case of Bryncethin, the 95 per cent CI is 714 to 2,283 which is the biggest possible clue that it’s unwise to draw any conclusions on the basis of the figure.

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