The prevalence of prodromal features of schizophrenia in adolescence: a preliminary survey.

In most cases of schizophrenia the onset of frank psychosis is preceded by a period of prodromal features. This period has been relatively neglected by researchers and is potentially important in promoting early intervention. The prevalence of DSM-III-R schizophrenia prodrome symptoms was assessed as part (n = 657) of a large (n = 2525) questionnaire-based survey of high school students. Individual symptoms were highly prevalent and the prevalence of DSM-III-R prodromes ranged from 10 - 15% to 50%. Despite methodological weaknesses, the data suggest that DSM-III-R prodromal features are extremely prevalent among older adolescents and unlikely to be specific for subsequent schizophrenia. Clinically these features cannot be regarded as sufficient evidence of early schizophrenia and more accurate predictors of incipient schizophrenia need to be defined.