Of the 1,960 participants who reported having used antidepressants in the past year and responded to relevant questions, 1,826 (93.7%) reported using antidepressants for depression, anxiety, chronic pain, or to enhance performance. Participants could choose more than one reason. Of the 1,826 participants, 893 (52.4%) reported using antidepressants regularly for at least four weeks, 185 (10.6%) regularly for less than four weeks, and 748 (37.1%) from time to time. The analyses found statistically significant differences in patterns of use by reason for use (design-based F=18.52, df=4 and 7,217, p<.001). As Figure 1 shows, individuals with more than one reason for use and those with depression were most likely to report regular use for four weeks or longer (65.7% and 63.3%, respectively); whereas only a minority of those citing performance enhancement reported regular use (18.0%). The percentages with anxiety and chronic pain reporting regular use for four weeks or longer fell in the middle—34.7% and 45.8%, respectively.