“…Six of these studies included substantial percentages of endogenously de pressed patients (39-100%) [3-5, 7, 9, 10], and four included inpatients [3,5,9,10]. Five of the seven studies [3,6,7,9,10] involved a 6-week trial; the remaining two [4,5] used a 4-week protocol. Amitriptyline was the comparative agent in four of the seven trials [6,7,9,10]; imipramine was the comparative agent in the remaining three [3][4][5].…”