Hysteria (Briquet's Syndrome) and sociopathy cluster in the same families instead of segregating as independent traits. Assortative mating between hysterics and sociopaths increases the observed similarity between relatives, but the familial association between sociopathy and hysteria remains after taking assortative mating into account. The Multifactorial Model of Disease Transmission with three thresholds related to severity and sex accounts for population and family data about sociopathic men, sociopathic women, and women with hysteria. The data were obtained for 227 first-degree relatives and for 800 subjects in the general population.
Depending on the sex of the individual and its severity, the same aetiological process may lead to different, sometimes overlapping, clinical pictures. Specifically, analysis indicates that hysteria in women is a more prevalent and less deviant manifestation of the same process that causes sociopathy in women.