To date, 12 placebo-controlled studies have evaluated the antidepressant efficacy of duloxetine at dosages of 40–120 mg/day. Many of these had an active drug comparator group. Efficacy was measured by remission, the optimal outcome measure, or by response. Remission can be operationally defined as a score of less than or equal to 7 on the 17-item Hamilton Rating Scale for Depression (Ham-D) or a score of less than or equal to 10 on the Montgomery-Åsberg Depression Rating Scale (MADRS). Response is often defined as a 50% reduction in the MADRS or Ham-D score from baseline to endpoint. These studies and non-placebo-controlled duloxetine trials are summarized in Tables 23–2 and 23–3.