This study aims to examine the effect of transformational leadership on organizational citizenship behavior (OCB) by considering group cohesiveness as a mediating variable. This study is motivated by the important role of leadership and work group dynamics in encouraging employee contributions that go beyond formal duties. The research method used is quantitative with a survey approach to 278 employees of PT Pema Global Energi. Data collection instruments include transformational leadership scale, group cohesiveness scale, and OCB scale which have been tested for validity and reliability. Data analysis was conducted using Partial Least Squares Structural Equation Modeling (PLS-SEM) technique. The results showed that transformational leadership has a positive and significant effect on OCB, both directly and through group cohesiveness as a partial mediator. In addition, it was found that group cohesiveness significantly strengthened the relationship between transformational leadership and OCB. These findings confirm the importance of developing an inspirational leadership style and creating a cohesive work environment to encourage employees' prosocial behavior. This study provides theoretical contributions in the development of organizational behavior models, as well as practical implications for management in improving effectiveness and productivity through leadership interventions and strengthening work group ties
Rizky et al. (Mon,) studied this question.