Using Intensive Longitudinal Data to Study Treatment Effects in Patients with Major Depression: A Systematic Review

Depression is a disabling condition, causing suffering worldwide. The purpose of this paper is to review studies that have used Intensive Longitudinal Data (ILD) in research on depression treatment. Intensive longitudinal data in the form of daily diaries, experience sampling method (ESM), and ecological momentary assessment (EMA) are increasingly used in psychotherapy research to gather individualized data. A systematic search was conducted in the research databases PsycINFO, PubMed and Scopus on depression treatment assessed with ILD methods. Seven studies met inclusion criteria; two focused on the effects of cognitive therapy/cognitive behavioral therapy (CBT)/Self-System Therapy (SST); one focused on the effects of physical exercise; and four examined ESM as an add-on intervention to pharmacological treatment. ILD is useful when studying changes in complex patterns of patients' functioning, such as daily affective reactivity, empowerment, daily dose-response effects of physical activity on PA, and associations between activity and depressive symptoms. Results also showed that ESM registration in itself can help patients with major depression (MDD) to engage more in physical and social activities and to spend less time alone or resting.