Jan. 29, 2009— -- To rate the 12 antidepressants studied, researchers used two separate measures. The first was efficacy -- or how likely patients were to experience the desired effects of the drug. The second was acceptability -- the likelihood that a patient would continue using a drug for the duration of the study (it is generally assumed that a high ratio of patients dropping out indicates the presence of undesirable side effects for a drug).
Source: Cipriani et al, "Comparative efficacy and acceptability of 12 new-generation antidepressants: a multiple-treatments meta-analysis." Lancet (2009).