JMIR Publications

ABSTRACT

Background:

Depression is a leading cause of disability. Two strategies that have been suggested to reduce the public health burden of psychopathology are identifying populations at risk for depression and disseminating scalable interventions. Online workers have been identified as a population at risk of depression. Digital single session interventions (SSIs) have shown promise in the treatment of depression and anxiety in youth. We combined the strategies by studying the efficacy of the Common Elements Toolbox (COMET), an unguided SSI based on principles of cognitive-behavioral therapy and positive psychology, in a sample of online panelists that was recruited to have enough power to detect small effects of COMET.

Objective:

To investigate the efficacy of the COMET-SSI vs. a WLC in depression and other transdiagnostic mental health outcomes.

Methods:

We conducted an investigator-blinded, pre-registered randomized controlled trial (NCT05379881, [1]) comparing the SSI COMET to an 8-week waiting list control (WLC). Participants recruited from the online workspace Prolific were assessed for depression, anxiety, work and social functioning, psychological well-being, and emotion regulation at baseline and post-intervention at weeks 2, 4, and 8. The main outcomes were short (2-week) and longer-term (8-week) changes in depression and anxiety. The secondary outcomes were the 8-week changes in functioning, well-being, and emotion regulation. Analyses were conducted according to the intent-to-treat (ITT) principle with imputation (ITT-imputed), without imputation (ITT-unimputed), and using a per-protocol (PP) sample of individuals who completed their baseline treatment conditions. Additionally, we conducted sensitivity analyses to identify inattentive responders.

Results:

The sample was 61.96% women (n = 513) with a mean age of 35.74 (SD = 11.93), although they reported struggling with internalizing disorder symptoms earlier in life (M = 13.54, SD = 7.33). Almost all of the participants met tcriteria to screen for depression or anxiety on a validated screening scale. . Individuals in the WLC were more likely to complete the baseline rating task (n = 417, 99.52%) than individuals in COMET were likely to complete the COMET SSI (n = 379, 92.67%), however, these differences were small. Despite having a trial powered to detect small effects, there were no statistically or clinically significant differences between the conditions in any of the outcomes at any of the time points regardless of whether we considered the ITT-imputed, ITT-unimputed, or PP sample. Inattention did not moderate the treatment differences and removing inattentive respondents did not change the pattern of results.

Conclusions:

Despite evidence of engagement with the intervention, our results do not support the use of SSIs like COMET in online worker. Future work should explore alternate ways of intervening with online workers including deep personalization of SSIs or matching individuals to SSIs they may be most responsive to. Clinical Trial: Design: NCT05379881. Analyses: https://osf.io/63yzh