Phase 2a will include a watchful waiting (WW) condition and assignment to 1 of 2 treatment conditions: GBAT+I or GBAT+E.

Participants will be assigned to WW for 10 wks. They will not receive specific therapeutic services during WW, but a member of the study team will contact them at weeks 1, 2, 4, 6, and 8 to maintain engagement and monitor for clinical deterioration.

After WW, participants will be randomly assigned to one of the treatment conditions (GBAT+I or GBAT+E). All groups will consist of 10 weekly 60-90-minute GBAT group sessions. GBAT+I participants will attend four 30-minute individual booster sessions. GBAT+E participants will be asked to use booster materials between group sessions (e.g., worksheets, goal trackers, interactive learning activities)

WW group size is based on study feasibility and availability of resources. Additional participants will also be recruited at the end of the WW period to supplement group sizes.

Phase 2b will include assignment to GBAT+IE, which includes components of both GBAT+I (individual sessions) and GBAT+E (supplemental materials)

All groups will consist of 10 weekly 60-90-minute GBAT group sessions. Participants in the GBAT+I group will also attend 30-minute individual booster sessions, approximately between Weeks 4-5, 5-6, 6-7, and 7-8. Participants in the GBAT+E group will be asked to use booster materials in between group sessions (e.g., worksheets, goal trackers, interactive learning activities). Participants in GBAT+IE will participate in both the individual sessions and use of booster materials.

The GAD-7, assessed weekly, is a 7-item questionnaire of anxiety symptoms over the past week with all items on a "0" (not at all) to "3"(nearly every day) scale. Total scores range from 0 to 21; higher scores reflect greater levels of anxiety.

The ADIS-5 is a semi-structured diagnostic interview that assesses mood and anxiety disorders. The interview focuses on clinical threshold of symptoms to inform current diagnostic presentations. Clinician Severity Rating (CSR) is rated for each diagnosis to quantify the interference of symptoms on a scale from 0 ("not at all") to 8 ("debilitating"). A score of 4 and above denotes a clinical threshold.

The BRIEF is a standardized measure that captures executive functions or self-regulation in an everyday environment. The BRIEF is composed of 75 items within nine theoretically and empirically derived clinical scales that measure various aspects of executive functioning. These scales form a Behavioral Regulation Index and Metacognition Index, as well as an overall Global Executive Composite Each of the scales and indexes yields standardized scores that allow for comparison with adults of the same age and gender (T-scores with a mean of 50 and a standard deviation of 10). T-scores between 60 and 64 are considered "Mildly Elevated," while scores between 65 and 69 are considered "Potentially Clinically Elevated." T-scores above 70 are considered "Clinically Elevated" and may warrant clinical attention.

The MTPT is a behavioral task that evaluates persistence. The participant is asked to trace the outline of 3 stars (rated easy, medium, and difficult), one at a time. The thickness of each subsequent star's outline gets smaller, making it harder to trace. To increase distress, the cursor is programmed to operate in the opposite direction of the user's input. If the participant goes outside the outline, a buzzer sounds and puts the participant back at the start point. Prior to tracing any stars, the participant's affect is assessed using a 100-point scale (0 = none and 100 = extreme) to assess frustration, anxiety, happiness, irritability, difficulty concentrating, and physical discomfort. The participant traces the "difficult" star again, only this time they are given an option to quit. The participant's time is recorded to measure how long they persist on the final star, referred to as task persistence. Afterwards, they rate affect from 0-100 in order to assess change in affect.

The DTT is a behavioral task that evaluates an individual's willingness to persist at a task in spite of heightened frustration and distress. It uses the stimulus cards from the Wisconsin Card Sort Test. The DTT provides consistently negative feedback over a small number of trials (thus serving as a more "compact" distress induction) and by including the opportunity to escape after 20 trials, which provides a behavioral measure of distress tolerance.