Interventions delivered via mobile apps show particular promise in tackling the burden of common mental disorders. Appropriately targeting these interventions to at-risk populations is critical to their success. This pilot study aimed to assess the usability, feasibility, acceptability, and preliminary effects of an app-based intervention designed to target depressive symptoms in a stressed working population. Anchored, a smartphone app including a 30-day program of mindfulness and cognitive and behavioural therapeutic components, was tested in a pre-post pilot study with participants recruited via social media advertisements. Eligible participants (N = 81) were Australian adults who were employed and reported elevated stress levels on a single-item screening measure. Follow-up assessment occurred 5 weeks after baseline. The primary outcome measure was change in depressive symptoms, with secondary outcomes measuring change in anxiety, wellbeing, stress, resilience, exercise, alcohol use, absenteeism, and work performance. User feedback and in-app data were analysed to assess engagement and intervention adherence. At follow-up, there were significant reductions in depressive symptoms (t61 = 6.35; p < 0.001) and anxiety symptoms (t60 = 7.35; p < 0.001), along with significantly reduced cases of likely new onset depression compared to baseline (24% vs. 6%, p = 0.012). Significant improvements were also seen in wellbeing (t60 = -5.64; p < 0.001), resilience (t60 = -3.89; p < 0.001), stress (t61 = 11.18; p < 0.001), and alcohol use (t60 = 3.40; p = 0.001). Participants reported no significant changes in work performance, absenteeism or exercise. There were satisfactory levels of app usability, feasibility, and acceptability. Most participants found the app easy to use (93.2%), understood the app content well (83.0%), and rated the app highly or very highly overall (72.9%). User feedback suggestions were predominantly focused on improving app navigation and user interface. This pilot study provides encouraging evidence that Anchored has potentially beneficial effects, and is usable, feasible, and acceptable as an app-based intervention for the working population experiencing elevated stress. Further testing of Anchored in a randomised controlled trial is required to investigate its efficacy as an intervention for workplace mental ill-health.
Keywords: anxiety; depression; eHealth; mHealth; mental health; mobile app; prevention; smartphone; workplace.