Fig. 2

Scatterplots showing baseline cortisol (left), cortisol responsiveness after 1 h (R1; middle), and cortisol responsiveness after 2 h (R2; right) measured for each individual at the first (x axis) and second (y axis) measurement (12 individuals in each plot). The two housing groups are designated by shape and color. Baseline cortisol was not repeatable (R = 0, p = 0.5); cortisol responsiveness R1 and R2 were significantly repeatable (R1: R = 0.635, p = 0.019; R2: R = 0.764, p = 0.002). Lines for R1 and R2 are for visualization of the relationship and plotted from basic linear regression (second measurement ~ first measurement)