Fig. 3From: Inequalities at birth: stable socioeconomic differences in birth outcomes in three British cohortsSensitivity analyses for the mediation effect of maternal smoking in pregnancy for each cohort. The graph reports the correlation between the error terms in the mediator (Eq. 4) and outcome models (Eq. 5) and the NIE. Dashed line is the estimated NIE. Estimates obtained with 500 simulationsBack to article page