Allusive thinking in parents of schizophrenics. Meta-analysis.

Romney (J. Nerv. Ment. Dis. 178:481-486, 1990) performed a meta-analysis of studies examining psychometrically assessed "thought disorder" in the relatives of schizophrenics. He concluded that thought disorder was more prevalent in the relatives of schizophrenics than control subjects. The present review focuses on only those studies that measured "allusive thinking" using the Lovibond-Rapaport Object Sorting Test in parents of schizophrenics. Even when the meta-analysis included this more limited number of studies, it demonstrated that the parents of schizophrenics were 2.42 times more likely to obtain high scores on the Object Sorting Test, confirming replication of the original McConaghy (J. Neurol. Neurosurg. Psychiatry 22:243-246, 1959) finding. This effect remained significant when the original study was excluded from the meta-analysis. The predictive strength of parental Object Sorting Test score as a familial risk factor for the development of schizophrenia is discussed.