Background Many studies have demonstrated that an urban birth or upbringing increases
schizophrenia risk, but no studies have been able to distinguish between these effects. The
objectives of this study were to discriminate the effect of urbanicity at birth from an effect of
urbanicity during upbringing, and to identify particularly vulnerable age periods and a
possible dose-response relationship between urbanicity during upbringing and
schizophrenia risk. Methods Using data from the Danish Civil Registration System, we …