The Israeli High-Risk Study recruited children at high and low risk of developing schizophrenia. Participants who were eligible for the high-risk group had at least one Israeli parent who had been diagnosed with schizophrenia. Participants who were eligible for the low-risk or control group had no parents with diagnosed schizophrenia and were age and sex-matched to the high-risk group participants. Approximately half of the total cohort was raised in the Kibbutz (a type of Hebrew communal settlement), whilst the other half were raised in nuclear families in cities and towns in Israel. This resulted in a baseline cohort of 50 participants in the high-risk groups and 50 participants in the low-risk or control group.