Table 1. SNP heritability estimates of phenotypes before and after adjusting for the first 20 principal components of ancestry.

SEs in parentheses. EA, educational achievement.

	Unadjusted	Population stratification adjusted
EA age 11	0.498 (0.056)	0.451 (0.064)
EA age 14	0.545 (0.069)	0.509 (0.079)
EA age 16	0.607 (0.052)	0.605 (0.059)
Cognitive ability	0.453 (0.058)	0.417 (0.066)
Linear SEP	0.568 (0.047)	0.547 (0.054)
Binary SEP	0.372 (0.046)	0.337 (0.052)