Long lasting improvement compared to a control group?

Depression studies are basically useless without a control group. In any given depression cohort, a number of patients will spontaneously improve even if they receive placebo or no treatment at all. For many (lucky) people, depressive episodes simply resolve after some time, so capturing them in studies without control groups can produce misleading results.

I started to notice the lack of sleep mood boost once it was pointed out. Occasionally I’ll wake up 3 hours earlier than normal for no apparent reason and generally feel energetic and productive.