title: To Treat or to Prevent?: Reducing the Population Burden of Violence-related Post-traumatic Stress Disorder.
abstract: BACKGROUND
  Violence-related post-traumatic stress disorder (PTSD) remains a prevalent and disabling psychiatric disorder in urban areas. However, the most effective allocation of resources into prevention and treatment to reduce this problem is unknown. We contrasted the impact of two interventions on violence-related PTSD: (1) a population-level intervention intended to prevent violence (i.e., hot-spot policing), and (2) an individual-level intervention intended to shorten PTSD duration (i.e., cognitive-behavioral therapy-CBT).
  
  
  METHODS
  We used agent-based modeling to simulate violence and PTSD in New York City under four scenarios: (1) no intervention, (2) targeted policing to hot spots of violence, (3) increased access to CBT for people who suffered from violence-related PTSD, and (4) a combination of the two interventions.
  
  
  RESULTS
  Combined prevention and treatment produced the largest decrease in violence-related PTSD prevalence: hot-spot policing plus a 50% increase in CBT for 5 years reduced the annual prevalence of violence-related PTSD from 3.6% (95% confidence interval = 3.5%, 3.6%) to 3.4% (3.3%, 3.5%). It would have been necessary to implement hot-spot policing or to increase CBT by 200% for 10 years for either intervention to achieve the same reduction in isolation.
  
  
  CONCLUSIONS
  This study provides an empirically informed demonstration that investment in combined strategies that target social determinants of mental illness and provide evidence-based treatment to those affected by psychiatric disorders can produce larger reductions in the population burden from violence-related PTSD than either preventive or treatment interventions alone. However, neither hot-spot policing nor CBT, alone or combined, will produce large shifts in the population prevalence of violence-related PTSD.
authors.affiliation: From the aViolence Prevention Research Program, University of California, Davis, Sacramento, CA; bDepartment of Emergency Medicine, School of Medicine, University of California, Davis, Sacramento, CA; cDepartment of Epidemiology, University at Albany School of Public Health, Rensselaer, NY; dDepartment of Epidemiology, Columbia University Mailman School of Public Health, New York, NY; and eSchool of Public Health, Boston University, Boston, MA.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Cerdá
authors.forename: Melissa
authors.initials: M
authors.lastname: Tracy
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Keyes
authors.forename: Sandro
authors.initials: S
authors.lastname: Galea
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015928:Cognitive Behavioral Therapy; D003198:Computer Simulation; D005260:Female; D006801:Humans; D035846:Law Enforcement / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D015233:Models, Statistical; D009519:New York City; D011322:Primary Prevention / Q000379:methods*; D013313:Stress Disorders, Post-Traumatic / Q000209:etiology / Q000517:prevention & control / Q000628:therapy*; D014754:Violence / Q000517:prevention & control* / Q000523:psychology; D055815:Young Adult