| Prevalence |
Approximately 1% of people worldwide have schizophrenia (Gottesman, 1991; Tandon et al., 2008). |
| Comorbidity |
Over 90% of people with schizophrenia also have at least one other disorder. The most frequent comorbid disorders are mood, anxiety, and substance use disorders. |
| Onset |
Men are more likely to develop the disorder in their early 20s, whereas women are more likely to develop it in their late 20s or later. |
| Course |
About two thirds of people who have had one episode will go on to have subsequent episodes. About one third of people with schizophrenia become chronically ill, without much reduction of symptoms; for most others, the symptoms subside. |
| Gender Differences |
Schizophrenia affects men more frequently than women (1.4 : 1 male-to-female ratio; McGrath, 2006), and—as noted above—women tend to develop the disorder at older ages than do men. Women have fewer negative symptoms than do men. |
| Cultural Differences |
Schizophrenia is more common among people in urban areas and in lower socioeconomic groups (Freeman, 1994; Saha et al., 2005). In non-Western countries, people with schizophrenia generally function better in society than do those in Western countries (Hopper et al., 2007). In a given country, immigrants are almost twice as likely to develop schizophrenia as are native-born residents (Saha et al., 2005). Within the United States, Latinos and Whites are less likely to be diagnosed with schizophrenia than are Blacks (Zhang & Snowden, 1999). |
| Source: Unless otherwise noted, citations for above table are: American Psychiatric Association, 2000, 2013. |