Online

Norton, Richard J.

Psychology

2022

M.A.

This is an exploratory network intervention analysis (NIA) of a larger randomized controlled trial comparing two first-line treatments for winter seasonal affective disorder (SAD): light therapy (LT) and group cognitive-behavioral therapy for SAD (CBT-SAD). Of 177 adults with SAD randomized in the parent study, this study included the 159 participants (88 LT, 75 CBT-SAD) who completed treatment. NIA was applied to examine the relation of treatment type to changes in four previously identified symptom clusters on the Beck-Depression Inventory-II extended version. There were no differences between LT and CBT-SAD in the magnitude of symptom cluster score changes in the interval from pre- to mid-treatment or from pre- to post-treatment. From pre- to mid-treatment, changes in Loss of Vitality, Dysregulation, and Negative Cognition were associated with each other while changes in Increased Appetite and Weight were unrelated to changes in the other clusters. From pre- to post-treatment, again changes in Loss of Vitality, Dysregulation, and Negative Cognition were associated with each other, and changes in Increased Appetite and Weight were (relatively weakly) associated with changes in both Negative Cognition and Loss of Vitality. This study contributes to understanding the relationship of treatment to subsequent changes in SAD symptom clusters and associations between changes in the symptom clusters themselves. Future work should examine the directionality of these associations and the mechanisms underlying them.