Official statistics are irritating

http://news.bbc.co.uk/1/hi/world/asia-pacific/7863290.stm says

'A 2007 commission report said the rate of [birth] defects [in Shanxi province, the centre of China's coal-mining industry] had risen 40% since 2001, from 104.9 per 10,000 births to 145.5 in 2006.'

This figure seemed to need some context, so I wandered over to google, and found

http://www.independent.co.uk/life-style/health-and-wellbeing/health-news/mediterranean-diet-reduces-birth-defects-525272.html

which says

'The French rate of 39.7 babies born with birth defects per 1,000 live births is less than half that in the Sudan, which has the highest rate in the world, at 82 per 1,000 live births. The UK ranks ninth in the table, behind Spain and Italy, with 43.8 affected babies per 1,000 live births'

and cites the March of Dimes, who provide me with

http://www.marchofdimes.com/MOD-Report-PF.pdf

which has a graph across the bottom of pages 9-10 which matches those figures, and has 51.2 defects per 1000 live births for China.

Is it more likely that the Shanxi figure should be per 1000 births, in which case Shanxi is a complete disaster area - sixty thousand babies born with defects a year - or that the Shanxi figures count only the really obvious immediately-visible birth defects and the March of Dimes figures count minor heart problems which require some work to discover?

"a child was born with physical defects every 30 seconds" => 1M per year; China's birth rate is 13.7 / 1000 people / year = 18.2 million per year, which gives a 5.5% figure that matches the March of Dimes.

I've written to the BBC about this and will be interested to hear what they say.