INTRODUCTIONDisruptive clinician behavior (DCB) refers to unethical and unprofessional behavior that seriously affects patient safety by disrupting relationships among healthcare professionals and causing dysfunctional communication and teamwork. DCB often persists as an organizational culture in Japanese healthcare settings because of problems in the conventional leadership system along with professional and positional hierarchies. Therefore, this study verified a causal model of DCB in Japanese healthcare, including triggers, response, and impact.METHODSStaff at two general hospitals (751 and 661 beds) were surveyed using a web-based questionnaire. In total, 256 staff who had experienced victimization and agreed to complete the questionnaire were included in this study. The questionnaire comprised demographic information, a DCB scale, and items covering causal indicators of DCB: triggers, response, and impact (psychological/social and medical/management).RESULTSMediation and moderated mediation analyses showed that: (1) DCB had a negative impact on the medical/managerial state, which was partially mediated by psychological/social impact; and (2) the responses of victims and others acted as a bulwark in reducing the psychological/social impact to some extent.DISCUSSIONA prompt response to DCB as a bulwark reduces victims’ psychological and social adaptation deterioration. Therefore, occurrences of DCB should not be overlooked, and the victim and those around them should respond positively. However, response as a bulwark cannot protect the organization’s medical care and management. Therefore, it is important to prevent DCB.