Table 1.

Differences between those included and excluded from analysis

	Included		Excluded
	Male	Female	Male	Female
Sexa	4675	4630	2960	2589
	Yes	No	Yes	No
Mother has degree	1330	8573	279	3920
Mother is home owner	6989	1633	2897	1982
Child from non-white ethnic background	332	8091	281	3447

^aData missing for 591 young people.