Effectiveness of the mobile application Holidaily in reducing work-related rumination when returning to work after vacation: a randomized controlled trial

Background: Vacations reliably improve indicators of mental health, largely by
providing relief from work-related stress. Low levels of work-related
rumination, a key transdiagnostic factor linked to burnout and depression, are
considered prerequisites for successful recovery both during vacations and in
daily working life. However, such benefits are typically short-lived, with a rapid
“fade-out” upon return to work. To address this challenge, we developed
Holidaily, a low-threshold, gamified mobile health intervention designed to
translate recovery science into daily digital practice and sustain the mental
health gains of vacations.
Methods: In a randomized controlled trial (RCT), Holidaily was evaluated as a
digital mental health intervention targeting work-related rumination, the
primary outcome. Assessments were conducted two weeks prior to vacation
and two weeks after the return to work, before waitlist controls were granted
access. Given the novelty of the research, a wide range of exploratory
outcomes was also assessed.
Results: A total of 190 workers from the general population were randomized to
either the intervention (n = 91) or waitlist control group (n = 99). ANCOVA, in
accordance with the intention-to-treat principle, indicated that the
intervention group reported significantly lower levels of work-related
rumination at two weeks post-vacation compared with controls [ p < 0.001,
d = −0.67 (−1.0; −0.4)]. At this time, rumination levels were still reduced by
22.2% in the intervention group, compared with 6.9% in controls relative to
baseline. Among app users, reductions persisted for up to four weeks (26.1%).
Sensitivity analyses confirmed these results. These findings provide first
evidence that a mobile health technology can extend vacation-related
recovery benefits and reduce work-related rumination in workers.Conclusions: This is the first RCT to show that the rapid fade-out of vacation
benefits is not inevitable. Holidaily appears to improve workers’ ability to reduce
levels of work-related rumination. These results highlight the potential of
scalable digital interventions to foster sustainable mental health in working
populations and support preventive public health efforts