Feasibility, acceptability, and effects of a self-stigma reduction pilot program for Japanese individuals with type 2 diabetes

•T2DM self-help psychoeducational self-stigma reduction program used patient stories.•A theory-based approach, integrating behavior change techniques was used.•The study examines feasibility, acceptability, and effects of the program for T2DM.•The program was acceptable, although its feasibility can be strengthened.•Results show that the intervention could help reduce levels of self-stigma.