Correlation between two factors doesn't tell you how to compare two sets of values. Kids who have to work after school until bedtime won't get as good grades in HS, but if no longer made to do so, may perform substantially better in college.
And that's the key. You're positing that the disadvantage magically stops in university.
I work in law school admissions prep, and you see these disadvantages all the way down the line: SAT, college grades, LSAT, law school grades, Bar exam passage rate
There are some cases where it stops. Maybe the college board can identify which variables may indicate a poor correlation. There might be some factors that indicate transient issues and some that indicate worse lifelong expectations.
But I'd be cautious about too readily assuming that a cause of a lower SAT will vanish in later life.
Actually, I should have been specific: you see disadvantages related to ethnic group down the line. If a group has a lower SAT score, they generally have the same gap on the LSAT, GRE, GMAT etc.
This is heavily related to socioeconomic status in the US. IIRC, in the UK for example you don't see these same gaps between ethnic groups. So it's something specific to US social circumstances, and not racial.
I don't know so much about particular circumstances, I just know what the high level stats say, and am inferring from that. I'm not American, so I don't have lived experience of the class structure there.
There are probably studies about income, but the test makers tend to only collect official data about ethnicity. It's commonly used as a proxy for social class, but I wish the test makers had better data about the elements the College Board is trying to capture with this new policy.
It's about one standard deviation between high scoring groups and low scoring groups across the tests.
LSAC no longer has theirs posted publicly, but it was much the same.
So, to the extent ethnicity is a proxy for social class in the US, we can say that the disadvantage these groups have at SAT time doesn't vanish by the time they take graduate level exams.
I wish I had some data for you that was based on social circumstances other than race, but I don't have deep knowledge in the domain, only what I've seen looking at the reports produced by the test companies recently.
