Background: There are conflicting results on the role of neuroticism as a risk factor for post-traumatic stress disorder (PTSD). The objectives of this study were to estimate the magnitude and direction of the association between neuroticism and PTSD, and to analyze the influence of different moderator variables on effect size.
Methods: A systematic review and a meta-analysis were carried out. The search for studies was conducted in Medline, IME, PsycINFO, Trip Database, and Google Scholar, until October 2012. A hand search was also carried out and main researchers were contacted.
Inclusion criteria: (a) empirical studies of the association between neuroticism and PTSD using validated scales or diagnostic criteria (DSM, ICD), (b) in participants exposed to a traumatic event and (c) written in English or Spanish. Two independent evaluators performed the selection and extracted the data following a previously developed protocol. The random-effects model was applied to obtain the mean effect size and to explore moderators.
Results: Out of 96 potential articles, 34 fulfilled the inclusion criteria (9,941 participants). The mean effect size was r+ = 0.371 (95%CI: 0.327 and 0.414). Publication bias was discarded as a threat. A predictive model was elaborated with three variables (reporting of ethnicity, age, and type of sample).
Conclusion: Neuroticism can be considered as a risk factor for PTSD in people who have been exposed to a traumatic event. These findings are relevant for developing preventive interventions and treatments.