RESUMEN
Although cross-sectional research highlights similarities between symptoms of obsessive-compulsive disorder (OCD) and posttraumatic stress disorder (PTSD) among individuals exposed to sexual trauma, little is known about how these disorders relate over time. The goal of the present study was to examine whether 1) OCD symptoms prospectively predicted daily symptoms of PTSD, and 2) OCD and PTSD symptoms prospectively predicted daily experiences of sexual trauma-related mental contamination (i.e., dirtiness in the absence of a physical pollutant). Forty-one women with a sexual trauma history completed baseline measures of OCD and PTSD, as well as twice-daily assessments of PTSD symptoms and mental contamination over a two-week period. Total OCD symptoms and the unacceptable thoughts dimension significantly predicted daily PTSD symptoms after accounting for other OCD dimensions. Only total OCD symptoms significantly predicted daily mental contamination when examined together with total PTSD symptoms. No individual PTSD or OCD clusters/dimensions significantly predicted daily mental contamination when examined simultaneously. Findings from this study highlight the nuanced associations among OCD symptoms, PTSD symptoms, and experiences of mental contamination. Future research is needed to further understand the development of PTSD, OCD, and mental contamination over time to inform targets for intervention.