Dallas 2K: A Natural History Study of Depression

D2K is a 10-year natural history, longitudinal, prospective study of a cohort of 2,500 participants that will help uncover the socio-demographic, lifestyle, clinical, psychological, and neurobiological factors that contribute to antidepressant treatment response: remission, recurrence, relapse and individual outcomes in depressive disorders. As this is an exploratory study, we will assess a comprehensive panel of carefully selected participant specific parameters: socio-demographic (age, sex, gender, race, ethnicity, economic); life habits (physical activity, substance use); clinical (medical history, anxious depression, early life trauma), biological (biomarkers in blood, saliva, urine, stool), behavioral (cognitive, emotional), neurophysiological (EEG), and neuroimaging (magnetic resonance imaging; MRI) with the goal of developing the most robust predictive models of depression treatment response and of outcomes. Clinician rated assessments, participant rated assessments, blood, saliva, stool, and urine collection, EEG, and MRI will be performed during the duration of the study. An optional m-health study may be collected continuously via a phone application and/or wristband over the course of the study. With this said, due to the nature of the protocol and the large number of research participants, we expect some appointments that include procedures and assessments to be missed within an expected study time frame. We will attempt to complete any missed appointments at the next scheduled visit. For the purposes of this study, missed procedures and/or assessments are not considered protocol deviations. In addition, the schedule of assessments to be completed will vary from time to time within this longitudinal study to help balance the data between age, sex, biological gender, gender identity, sexual orientation, gender expression, and diagnosis breakdown of our enrolled participants for data analyses. The schedule of assessments will NOT exceed the following: 1. Monthly Surveys: 12 times a year 2. MRI: up to 4 times a year 3. EEG: up to 4 times a year 4. Biospecimen collection: up to 4 times a year 5. Cognitive Behavioral Tasks: up to 4 times a year 6. Extensive Self-report and Clinician rated assessments: 4 times a year 7. Stool Sample collection: up to 4 times a year 8. Optional M-health: Duration of the study (starting from Baseline) Participants will be compensated based on the study activity they complete and will not exceed the total amount (per year) that is approved by the IRB. No study procedures will be conducted until signed informed consent has been obtained from the participant. Details regarding informed consent procedures are included in section 8. Procedures specific to youth 17 years old or younger: Participants will complete the questionnaires that have been normed and validated to their age with the assistance of study staff. Forms may also be completed by participant's parent(s)/guardian(s)/LAR as needed.