Paternal age effect

The paternal age effect is the statistical relationship between the father's age at conception and biological effects on the child. Such effects can relate to birthweight, congenital disorders, life expectancy and psychological outcomes. The effect of paternal age on a trait can be measured as the causal correlation of paternal age on that trait. This is done by regressing paternal age onto the trait with important covariates controlled for. Typically, these covariates are father's trait phenotype, maternal age, birth order, and participant age (since older people had younger fathers on average, any generational trend would correlate with paternal age without age controlled for).