Paternal age and schizophrenia: Authors' reply.

EDITOR—Procopio highlights the fact that our study included only subjects with a younger age of onset ranging from 16 to 28 and suggests that our finding of an association between paternal age and schizophrenia therefore needs to be interpreted cautiously. This association has already been replicated in a number of studies covering much wider ranges of age of onset: the Jerusalem cohort covered …