Effects of Self-Compassion and Mindfulness Interventions on Mental Health and Work-Related Outcomes Among Japanese Workers: Randomized Controlled Trial.

A 3-arm randomized controlled trial of 300 Japanese workers found no significant group × time interactions for most primary outcomes including psychological distress and work performance.

• 300 working adults were randomly assigned to self-compassion meditation (SCM, n=101), mindfulness meditation (MM, n=100), or waitlist control (n=99).
• Mean age was 35.44 years (SD 9.14); 60% (n=180) were female.
• Primary outcomes included the Kessler Psychological Distress Scale-6 and World Health Organization Health and Work Performance Questionnaire and Stanford Presenteeism Scale.
• Assessments were conducted at baseline, postintervention (4 weeks), and 1-month follow-up (8 weeks).
• No significant group × time interactions were detected for most outcomes.

Adherence to the smartphone-based meditation app was high in both intervention groups over the 4-week program.

• Mean completed days were 23.30 (SD 5.58) for the SCM group and 22.95 (SD 6.25) for the MM group out of a possible 28 days.
• The overall dropout rate was 21.4%.
• The program was fully self-guided without facilitator support.
• Recruitment occurred in 2 waves: November–December 2022 and June 2023, with follow-up completed by September 2023.

Significant main effects of time were observed for several measures including work performance and self-compassion, with small effect sizes.

• Main effects of time were significant across groups for work performance and self-compassion measures.
• Effect sizes were described as small.
• These effects reflect change over time across all participants rather than differential intervention effects.
• Within-group analyses suggested broader improvements in the SCM group, whereas changes in the MM group were more limited.

Sensitivity analyses using linear mixed-effects models detected a significant group × time interaction for work performance, with a larger pre-post improvement in the SCM group.

• The significant interaction for work performance was identified only in sensitivity analyses using linear mixed-effects models.
• The SCM group showed a larger pre-post improvement in work performance compared to the MM and control groups.
• This finding was not replicated in the primary analyses, limiting causal inference.
• The authors note this should be interpreted as preliminary and does not support strong causal claims of intervention superiority.

Traditional mindfulness and self-compassion interventions often require high time commitment, and low-intensity digital interventions remain underexplored in occupational health contexts.

• Mental health problems among workers are described as a significant global concern leading to substantial economic losses, particularly due to presenteeism.
• The study aimed to evaluate a smartphone-based self-care app enabling independent practice without facilitator support.
• The intervention was characterized as low-intensity.
• The study focused on a nonclinical Japanese worker sample, a population noted as underexplored in this literature.

Secondary outcomes assessed included cognitive flexibility, perceived stress, work engagement, psychological safety, and self-perceived creativity, with no strong differential intervention effects reported.

• Secondary outcomes encompassed cognitive flexibility, self-compassion, perceived stress, work engagement, psychological safety, and self-perceived creativity.
• No significant group × time interactions were detected for most of these secondary outcomes.
• The clinical significance of observed changes remains unclear given the nonclinical sample.
• The authors recommend future studies to evaluate clinical significance in relevant populations.