This meta-analysis of adolescents and young adults given IQ tests multiple times, the risk of schizophrenia increases about 55% for each standard deviation in IQ lost. This finding should be framed appropriately, however. The risk of schizophrenia is low and remains low, even when IQ drops. Most people in whom IQ drops do not go on to develop schizophrenia. However, the risk of developing schizophrenia is higher among people whose IQ drops significantly.