They worked with hundreds of primary school pupils aged four to nine at 20 carefully selected schools in Tyne and Wear,Northumberland,Lancashire,Gloucestershire and the West Midlands.

• 他们精心挑选了20所英国小学(分别位于泰恩·威尔、诺森伯兰、兰开夏、格罗斯特、西米德兰等地)，将其中4岁至9岁的几百名小学生作为研究对象。