Age-of-onset in schizophrenia and schizotypal disorders. Clinical and genetic implications

Neuropsychobiology. 1983;10(4):199-204. doi: 10.1159/000118011.


Age-of-onset data were gathered on 93 chronic schizophrenic probands and 57 affected (mainly schizotypal) siblings. 55% of affected individuals were ill before age 20 and 14% had their onset before age 14. The risk period for schizophrenia and schizotypal personality disorders terminated at age 40. Age-of-onset did not distinguish paranoid from nonparanoid schizophrenics, or definite from probable schizotypal personalities. Schizophrenic and schizotypal subjects were similar in their age-of-onset patterns. Sex effect on age-of-onset was not present. A square-root normal distribution gave the best fit to the data. The implications of these findings for schizophrenia research were discussed.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Aging*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Schizophrenia / physiopathology*
  • Schizotypal Personality Disorder / physiopathology*
  • Statistics as Topic