Fig. 2.

Effects of PI status on morning cortisol depend on age. (A) Fitted results of piecewise Age X Group effects on morning cortisol are depicted. Raw cortisol values (lines connecting within-subject observations) are shown with a 95 % CI band around the fitted regression lines. (B) The region of significant plot is shown, depicting the magnitude of group differences in morning cortisol (PI – COMP) across the entire age-range. When the 95 % CI band is above zero, morning cortisol is significantly higher in PI group than the comparison group, and when the 95 % CI is below zero, morning cortisol is significantly lower in the PI group than the comparison group. * p < 0.05, ** p < 0.01.