Reducing Dropout and Improving Outcomes From PTSD Therapy: When to Switch Therapies or Stay the Course

Investigators' overall objective is to compare methods of identifying individuals who may be experiencing challenges in Cognitive Processing Therapy (CPT) and compare methods of intervening to optimize treatment retention and outcomes. Investigators' specific aims are: 1. to determine whether the use of CPT skills versus collaboratively considering switching to Present Centered Therapy (PCT) is more effective in improving outcomes for individuals experiencing challenges with CPT. Outcomes include post-traumatic stress disorder (PTSD) severity \[primary\], depression, functioning, and treatment retention; 2. to compare two approaches to identifying individuals in CPT in need of additional support during treatment; 3. to study the barriers and facilitators of implementing these intervention strategies. Finally, exploratory aims will examine the stability of differences between treatment conditions, compare combinations of interventions tested, and examine moderators of intervention effects.