The relationship between maternal level of conscientiousness and parenting stress in the MTA and LNCG samples. Conscientiousness (x axis) was centered on the pooled sample mean. Conscientiousness protects against parenting stress for LNCG mothers, who do not have a child with ADHD, but not for MTA mothers, who have a childwith ADHD. The diverging lines suggest that having a child with ADHD neutralizes the protective effect of conscientiousness against parenting stress. Estimate intercept differences between groups at different levels of conscientiousness (pooled −2SD, −1SD, Mean, +1SD and +2SD) are offered with their respective 95% CI in the right panel. The dark dots represent sample means for the MTA group (upper left) and the LNCG (lower right).