Many councils would be able to make significant savings by identifying and eliminating the causes of differences in costs, it added.

BBC: Audit Commission urges social care savings of ?300m

Survival rates for breast cancer in the UK in particular have improved and while the researchers will examine the causes of the differences in future papers, it seems late diagnosis of cancer remains a problem.

BBC: UK cancer survival rates lag behind other countries

OK, all this is a long way short of proof that traffic density alone causes these differences.

BBC: Crashes

Ms Pinker is surely right that understanding the causes of workplace gender gaps, rather than mulishly insisting sex differences do not exist, will ultimately be better for both women and men.

ECONOMIST: Men, women and work