Obiective: The authors sought to evaluate uhether the pattern of schizophrenia and related
disorders in probands and their relatives can be explained by a single underlying continuun
of liability to the “schizophrenia spectrum." Method: In the epidemiologically based
Roscommon Family Study, the authors separately examined–in siblings, parents, and
relatives of index and comparison probands–the familial aggregation and coaggregation of
five hierarchically defined disorders: schizophrenia, schizoaffective disorder …