Effects of cognitive therapy for depression on daily stress-related variables.

This study used a daily diary design to evaluate depressed patients' changes on daily stress-related variables during cognitive therapy (CT). Patients completed daily diaries on two week-long occasions: after the intake interview and again after the sixth session of CT. Patients also completed a measure of depressive symptoms before every treatment session. After six sessions of CT, patients reported a significant reduction in: (a) depressive symptoms; (b) daily sad affect (SA); (c) daily negative thoughts associated with the day's most stressful event; and (d) SA reactivity to daily stressors. In addition, patients reported a significant increase in: (e) daily positive affect (PA); and (f) SA reactivity to daily negative thoughts. The results suggest that CT has its intended effects on the daily lives of depressed adults, and highlight the value of a daily diary methodology for research on CT.