Conditional average treatment effect: an application related to the partner union quality and divorce on the child’s psychological wellbeing

We test the hypothesis that divorce may be a positive experience for children with parents in high-distress unions, while the dissolution of low-distress unions may have negative effects. We use the first three waves of the Millennium Cohort Study (MCS), a longitudinal and representative British survey, to explore parental divorce and parent relationship quality on several children's outcomes at age five. By using the augmented inverse propensity weighted estimator we show that the dissolution of high-quality parental unions has the most harmful effects on children, especially on conduct problems. Among children whose parents have the highest-quality relationships, those that experience parental separation/divorce have higher conduct problems than children with a stable family. Our findings indicate that early childhood programs and interventions should particularly target children whose parents report high quality relationship before parental separation since they are especially at risk