For cognitive performance, the ratio was better, but it’s not 0.824, it’s .
That’s variance explained. I was talking about effect size attenuation, which is what we care about for editing.
I checked supplementary table 10, and it says that the “direct-population ratio” is 0.656, not 0.824. So quite possibly the right value is even for cognitive performance.
Supplementary table 10 is looking at direct and indirect effects of the EA PGI on other phenotypes. The results for the Cog Perf PGI are in supplementary table 13.
Not quite sure which numbers you’re referring to, but if it’s the assumed SNP heritability, see the below quote of mine from another comment talking about missing heritability for IQ:
The h^2 = 0.19 estimate from this GWAS should be fairly robust to stratification, because of how the LDSC estimator works. (To back this up: a recent study that actually ran a small GWAS on siblings, based on the same cognitive test, also found h^2 = 0.19 for direct effects.)