Background. In contrast with the large amount of research on the familial transmission of antisocial behaviour, few studies have investigated similarity between spouses for such behaviour. In addition, none of these studies have examined child conduct disorder (CCD) and adult antisocial behaviour (AAB) separately.

Method. We studied 519 pairs of spouses who completed the Diagnostic Interview Schedule. In each pair, one spouse belonged to a random subsample of persons who had participated in a large population survey and was re-interviewed. Association between spouses for lifetime symptoms and DSM-III criteria of CCD, AAB, antisocial personality disorder and co-morbid psychiatric diagnoses was examined with bivariate and multivariate logistic regression analyses.

Results. We observed a moderate association between spouses for the presence of CCD (OR=4·02, 95% CI=2·03–7·96), and a strong association for the presence of AAB (OR=20·1, 95% CI=5·97–67·5). This similarity for AAB was independent of the similarity for CCD and persisted after adjustment for spousal similarity for disorders co-morbid with AAB. An examination of the relationship between marital status and the presence of CCD and/or AAB in the general population sample (from which originated our sample of couples) suggested that the spousal similarity for AAB was more likely attributable to assortative mating rather than marital contamination.

Conclusion. Our finding of a strong similarity between spouses for AAB has significant implications for both clinicians and researchers. It also suggests that adult antisocial behaviour should be considered as a distinct diagnostic entity, an approach which diverges from DSM-IV diagnostic criteria.