Design of The EMC Trial. Abbreviations: d = study day; ESC = Escitalopram; LI = Lithium; t = time point; VEN = Venlafaxine; EMC = early medication change group; TAU = treatment as usual group; IML2 = improver group level 2; IML3 = improver group level 3. Definitions: improvement = reduction of HAMD17 sum score ≥20% in a specified time span, e.g. between time point (t) 0 and t1; non-improvement = reduction of HAMD17 sum score <20%; response = reduction of HAMD17 sum score ≥50%; non-response = reduction of HAMD17 sum score <20%. Grey boxes indicate randomized groups (non-improver t0-t1; non-improver 2/t2-t3; non-improver 3/t2-t3).