Peace and Conflict: Journal of Peace Psychology, Vol 32(2), May 2026, 151-162; doi:10.1037/pac0000823
This study explored a short-term program’s effectiveness in teaching the integrating conflict resolution skills to Japanese junior high school students. The primary variable was the integrating conflict resolution skills, and secondary variables included friendship satisfaction, school enjoyment, and psychological stress response. Utilizing a multiple-baseline design, the program was implemented among eighth-grade students (103 in the late-winter group, 117 in the early-winter group, and 108 in the fall group; 159 boys, 166 girls, and three unidentified) through two 50-min sessions conducted in different seasons over a 3-year period. With a linear mixed model, intention-to-treat analysis showed interaction between intervention time and implementation season in the integrating conflict resolution skills. Intervention time and implementation season also had a main effect on friendship satisfaction, and implementation season had a main effect on psychological stress responses. Results were discussed according to the perspective of effective implementation and future direction. (PsycInfo Database Record (c) 2026 APA, all rights reserved)