Augmenting Internet-Based Cognitive Behavioral Therapy for Major Depressive Disorder With Low-Level Light Therapy

1. Online screening Following a digital informed consent, all participants will complete a brief online screening questionnaire to determine the severity level of their depression, using the Center for Epidemiological Studies - Depression Scale (CES-D). Initial consent and screening procedures will be conducted online via Research Electronic Data Capture (REDCap), a secure, on-line assessment tool designed to collect self-report questionnaire data for research studies. Participants with a CES-D score of 16 or higher will be eligible to continue with the study. At this initial screening, eligible participants will also provide contact information (name, email address, and phone number) for a follow-up phone screening.
2. Phone screening Following the online screening, eligible participants will complete a phone screening, the Mini International Neuropsychiatric Interview (MINI), conducted by researchers in the Mood Disorders Laboratory. The phone screening will be audio recorded for quality control purposes. Participants will be eligible to continue on in the study if they meet criteria for current Major Depression without any comorbid disorders, excluding anxiety disorders. Next, participants will complete the Colombia-Suicide Severity Rating Scale (C-SSRS) to assess for suicidality. Any participant who endorses suicidal intent, with or without plan, (i.e., items 4 or 5) within the last six months, will be deemed ineligible. Researchers will provide resources to any participant endorsing suicidal ideation, and will contact authorities if necessary. At the end of the phone screening, eligible participants will be scheduled to come into the Mood Disorders Laboratory for their initial study meeting within a week.
3. Initial meeting

Participants deemed eligible by the online and phone screenings will come into the Mood Disorders Laboratory within a week of their phone screening. The initial meeting will last approximately one hour. The initial meeting will have several objectives:

First, participants will provide informed consent. Research personnel will provide participants with detailed oral and written description of all study procedures in order to ensure understanding of all components of the study. Participants will provide informed consent for completing the Deprexis program, pre-treatment questionnaires, daily questionnaires, weekly questionnaires, and post-treatment questionnaires. All questionnaires will be accessed online via REDCap.

Next, participants will complete several pre-treatment questionnaires. Also, researchers will introduce the Deprexis program, and participants will receive an access code that will allow them immediate access to the Deprexis site. Information about the Deprexis program is detailed below.

Participants will also complete an eye tracking/pupil dilation task during the meeting. Pupil dilation response to emotional stimuli has been shown to be related to depression. In this pupil dilation task, participants will passively view emotional and neutral stimuli (images). More details about the task are below. 4. Pre-treatment questionnaires Participants eligible to take part in the Deprexis program will complete several pre-treatment questionnaires at the initial meeting. 5. Deprexis All Deprexis treatment will be provided via the Deprexis website: http://deprexis.com/. Participants will have access to this website for twelve weeks. They can access this website as often as they would like. The Deprexis program is self-guided, so participants determine how often they access the material (see below for a description of the Deprexis treatment).