Reducing public stigma toward people with mental illness through the ACE intervention: a cluster-randomized waitlist-controlled trial.

BACKGROUND

Mental illness stigma remains a major barrier to mental health in many parts of the world, including China, where public stigma is particularly pervasive among university students. The Acceptance and Commitment to Empowerment intervention (ACE), an integration of Acceptance and Commitment Therapy and Group Empowerment Psychoeducation, was adapted and piloted in a Chinese university context. This study aimed to evaluate the effectiveness of the ACE intervention in reducing both explicit and implicit public stigma toward people with mental illness among Chinese university students.

METHODS

We conducted a cluster-randomized waitlist-controlled trial at a university in Shandong Province, China, with a total of 111 students participating. Participants were randomly assigned to either an intervention group or a control group. The ACE intervention combined a self-paced online course on mental health literacy with a five-day, in-person experiential training focused on acceptance, mindfulness, values, and empowerment. Explicit stigma was assessed using self-report questionnaires (Attribution Questionnaire-9 and Social Distance Scale), while implicit stigma was measured through a Single-Category Implicit Association Test (SC-IAT).

RESULTS

Mixed-measures ANOVA revealed a significant reduction in explicit stigma in the ACE intervention group over time, with no significant change in the control group. SC-IAT scores indicated that participants in the ACE group had significantly lower levels of implicit stigma compared to the control group.

CONCLUSIONS

This study provides preliminary evidence that the ACE intervention can effectively reduce public stigma among Chinese university students. The findings support the cultural adaptability of ACE and offer insights for implementing stigma-reduction programs in China. Recommendations for future research are also discussed.

TRIAL REGISTRATION: Retrospectively registered with the Chinese Clinical Trial Registry (ChiCTR2500105456). Date of registration July 3, 2025.