For DEP, going from GWAS to MTAG, the mean χ2-statistic increases from 1.44 to 1.60, implying an increase in the GWAS-equivalent sample size by a factor of 1.550−11.434−1=1.26.Thus, the MTAG analysis has statistical power equivalent to a GWAS of DEP conducted in 354,861×126%=449,649 individuals. For NEUR, the mean χ2-statistic rises from 1.284 to 1.557, implying a GWAS-equivalent sample size for MTAG that is 96% larger than the GWAS sample size: the effective sample size is 168,105×196%=329,835 individuals. For SWB, the mean χ2-statistics rises from 1.308 to 1.570, implying a GWAS-equivalent sample size 85% larger than the GWAS: 388,538×185%=718,284 individuals (Supplementary Table 11).
