Partial effects plots showing the smooth of time-corrected cortisol and age for females (a, edf = 2.70, p = .13) and males (b, edf = 3.24, p < .001) and partial parametric effect of male sex compared with female as the reference sex on time-corrected cortisol (c, m = 0.21, p = .03). Overall comparison of time-corrected cortisol between males and females (d) also shown for reference