the variance. Rather, the small sample and low precision studies will be more likely to estimate heritability to be lower than the high precision studies due to the greater amount of sampling variability. Alternatively, it may be the case that the low precision estimates are indicative of substantial heterogeneity of effect sizes. Our moderation analysis was unlikely to detect this heterogeneity on the basis of the measured moderators as the datapoints carried little weight in the analysis. It may also be the case that the heterogeneity is due to moderators that we did not choose to evaluate. More high precision studies of early child development would be necessary to evaluate this issue with greater accuracy.
