A Daily, Digital Mindfulness-Based Intervention for Depressive Symptoms After Serious Illness - ABSTRACT Depression is highly prevalent among people with serious medical illness, like cancer, and is associated with adverse outcomes, including worse disease course and increased disability and mortality, making management of depressive symptoms in medically ill populations a priority. Patients who recently completed treatment for cancer, a challenging adjustment period for many, are at especially high risk for experiencing depressive symptoms, that when left unaddressed, confer risk for recurrence and earlier mortality. Mindfulness-based interventions (MBI), like Mindfulness-based Cognitive Therapy (MBCT), effectively reduce depressive symptoms in cancer survivors. However, because most MBIs are group-based, time intensive, difficult to scale, and can be costly, only a small portion of patients ever engage with MBIs. Of those that do, adherence to at-home practice is suboptimal in cancer survivors, an indication that currently prescribed daily practice dosages may not be feasible or accepted by this population. Thus, to increase reach, scalability, feasibility, and acceptability of MBIs for depressive symptoms in post-treatment cancer patients, a new approach is needed. The candidate will address this need by adapting core components of MBCT-Brief (an abbreviated version of MBCT) into a novel, daily, digitally delivered format: 15 minutes of audio content delivered via text message daily for 8 weeks. First, the candidate will develop the daily Mindfulness-based INtervention for Depressive symptoms SEnt via Text (MINDSET) for post-treatment cancer patients. Then, the candidate will conduct a single-arm pilot study to test and refine MINDSET using participant feedback via a mixed methods approach (i.e., quantitative survey and qualitative focus group data). Finally, the candidate will conduct a randomized controlled trial to test the feasibility and acceptability of MINDSET and the control condition (Enhanced Usual Care). Findings from this research will provide data for an R01 application to conduct an adequately powered randomized controlled trial to test the efficacy of MINDSET in reducing depressive symptoms. The proposed Mentored Patient-Oriented Research Career Development Award (K23) will provide the candidate with training and hands-on experience in 1) adapting an evidenced-based intervention for depression digitally; 2) conducting qualitative and mixed methods research; and 3) clinical trial design and conduct, skills that the candidate needs to conduct high-impact rigorous research in integrative health interventions. The candidate will carry out the proposed training and research in an outstanding research environment under the guidance of an exceptional team of mentors, advisors, and consultants who are experts on these topics and are dedicated to her career development. The proposed award will provide the candidate with the in-depth experiences needed to establish an independent program of patient-oriented research focused on whole-person integrative health interventions, including those for depression and common serious medical illnesses, like cancer.