Monthly Trajectories of Mood Improvement Following a Workplace Mindfulness Programme: A Randomised Controlled Pilot Trial

This pilot randomized controlled trial aims to evaluate the month-by-month effects of a low-intensity workplace mindfulness-based intervention (MBI) on mood among full-time employees in a healthcare setting in Okinawa, Japan. Participants are assigned in a 1:1 ratio to either the MBI group or a wait-list control group. The intervention consists of three 90-minute in-person workshops delivered at monthly intervals, incorporating psychoeducation, guided stretching, and focused-attention meditation. Participants in the MBI arm are also encouraged to practice mindfulness at home for 10 minutes per day. Mood is assessed at baseline and monthly over three months using the Japanese POMS2 Short Form. The primary endpoint is change in Total Mood Disturbance (TMD); secondary outcomes include fatigue (measured via a visual analogue scale) and presenteeism (measured via Single-Item Presenteeism Question, the University of Tokyo single-item edition (SPQ) ). Linear mixed-effects models are used for statistical analysis. The study is approved by the Ryusei Hospital Institutional Review Board (Approval No. 2024-02) and conducted as a feasibility study without prospective registration.