Magnitude of reaction time crossover in process schizophrenic patients in relation to their first-degree relatives

The reaction time crossover (redundancy associated deficity) scores of 28 process schizophrenics, selected for the presence of crossover, were correlated with the crossover scores of 53 of their first-degree relatives (one to five relatives for each patient.). The resulting product-moment correlation coefficient was .27 (p < .05), thus lending support to the notion of a familial factor in reaction time crossover.