JMIR Publications

ABSTRACT

Background:

Breast cancer is the most diagnosed cancer among women worldwide. Although many survivors experience anxiety, depression, and other psychological challenges during survivorship, access to mental health care is often limited by clinician shortages, cost, and time. Mobile health applications may offer an accessible, scalable, and low-cost approach for delivering psychological support.

Objective:

This study evaluated the feasibility, acceptability, usability, and preliminary mental health outcomes of WithYou PINK, an app co-designed with breast cancer survivors and grounded in Acceptance and Commitment Therapy (ACT).

Methods:

This 6-week single-arm pilot study was conducted from March to May 2026 in Indianapolis, Indiana, USA. Eligible participants were diagnosed with stage I–III breast cancer, had completed primary treatment within the previous 5 years, and reported moderate to severe anxiety (Generalized Anxiety Disorder-7 [GAD-7] score ≥10) and/or moderate depressive symptoms (Patient Health Questionnaire-8 [PHQ-8] score 10–19) at screening. Participants used the WithYou PINK app, which included 40 ACT-based activities designed to support adaptive coping. Feasibility was assessed through intervention completion, while acceptability and usability were evaluated using the Acceptability E-Scale (AES) and System Usability Scale (SUS). Changes in anxiety, depression, other mental health outcomes, and quality of life were examined using pre-post assessments.

Results:

Participants (N=34) had a mean age of 52.7 years (SD = 10.7), and all were female. More than half (55.9%) of study participants completed all 40 activities in the app, demonstrating feasibility. Mean AES (27.6) and SUS (87.9) scores exceeded established thresholds for good acceptability and usability. Pre-post analyses demonstrated statistically and clinically significant improvements in anxiety (GAD-7: g = -1.30, 95% CI -1.75 to -0.84; p < .001), depressive symptoms (PHQ-8: g = -1.33, 95% CI -1.78 to -0.86; p < .001), and other mental health outcomes, with more modest improvements in quality of life.

Conclusions:

The WithYou PINK app demonstrated feasibility, acceptability, and usability among breast cancer survivors with elevated symptoms of anxiety and/or depression. Improvements in mental health outcomes observed over the 6-week intervention support the potential of this ACT-based app. A robust clinical trial is needed to provide the rigorous evidence necessary to justify clinical implementation.