DEPRESSION AND PARENTAL BONDING - CAUSE, CONSEQUENCE, OR GENETIC COVARIANCE

It is shown how information on the direction of causation between vari ables may be obtained from a cross-sectional study of pairs of relativ es. This method is applied to the study of the relationship between ra tings of parents' rearing style and depression in their offspring. Adu lt female twins ascertained from a population-based registry in Virgin ia completed the Center for Epidemiological Studies - Depression Scale (CESD) and a 7-item short form of the Parental Bonding Instrument (PB I) about each of their parents. Two dimensions of parental behavior, o verprotectiveness and coldness, were analyzed jointly with depression data in both genetic factor and directional genetic models. Models tha t specify ratings of parents as a cause of depression in the offspring fit the data significantly better than models that specify depression as a cause of ratings of parents. A still better fit is obtained with models that specify common genetic variance to depression and ratings , though causal models with error variance perform almost as well. In general, ratings of fathers show more genetic and less shared environm ental variance than ratings of mothers, which might arise from more co nsistent treatment of offspring by mothers than by fathers. No effect of children eliciting parental rearing style was detected with these d ata. The relative merits of instrumental variable, longitudinal, and f amily approaches to testing causal models are discussed. (C) 1994 Wile y-Liss, Inc.