Fig. 1: Approaches for defining response to antidepressants.

A Four representative participants for the three classes of antidepressant response definition approaches’ comparison with their original trajectories: “match” class [blue and red, dotted in (B, C)] represents 85% of participants, class 1 discrepancy (turquoise) 4.5%, and class 2 discrepancy (yellow) 10.5%; added in N are the numbers of participants in each group. B Response trajectory for the three classes according to the classic definition of 50% reduction in QIDS score (gray line). C Response trajectory for the three classes according to the exponential fit definition; participants with a slope steeper than the median (gray) are categorized as responders (blue and turquoise), and the rest (red and yellow) are categorized as nonresponders. [Both (B, C) include the time-points that were used in the calculation of the trajectories].