Mediating Role of Post-Traumatic Stress Disorder in the Relationship Between Trauma Exposure and Job Performance Among Police Officers in Njoro Sub-County, Nakuru County, Kenya

Police officers are frequently exposed to traumatic incidents that can impair their psychological wellbeing and job performance. This study examined the mediating role of Post-Traumatic Stress Disorder (PTSD) in the relationship between trauma exposure and job performance among police officers in Njoro Sub-County, Nakuru County, Kenya. The objectives were to assess the extent of trauma exposure, evaluate its effect on job performance, and determine whether PTSD mediates this relationship. The target population comprised 152 police officers drawn from all stations within Njoro Sub-County, from which a sample of 133 officers participated, yielding an 87.5% response rate. A descriptive and inferential research design was adopted, utilizing structured questionnaires as the primary data collection instrument. Quantitative data were analyzed using descriptive statistics, correlation analysis, multiple regression, and structural equation modeling (SEM) with the aid of SPSS and AMOS software. Results revealed that trauma exposure had a significant negative effect on job performance and that PTSD significantly mediated this relationship. Officers with higher levels of trauma exposure exhibited more severe PTSD symptoms such as irritability, hypervigilance, and emotional exhaustion which in turn reduced decision-making ability, concentration, and interpersonal functioning. These findings affirm that PTSD is a critical psychological pathway linking trauma to diminished performance in policing contexts. The study recommends that the National Police Service institutionalize regular psychological screening, counseling, and wellness programs to facilitate early detection and management of PTSD. Moreover, post-incident debriefing, peer-support systems, and mentorship programs should be integrated into operational protocols to enhance resilience and safeguard officers’ mental health and performance. Future research should adopt longitudinal and comparative designs to establish causal relationships and explore the moderating roles of organizational culture and gender in trauma response among police officers.

Job Performance, Kenya, Police Officers, Post-Traumatic Stress Disorder, Trauma Exposure

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