Multiphase Optimization Strategy (MOST) for Treating Pediatric Post-traumatic Stress Disorder (PTSD)

This study is working to find the best combination of therapy techniques for children and teenagers who have PTSD (post-traumatic stress disorder) after experiencing a traumatic event. Researchers are testing different treatment approaches — delivered partly via smartphone app — to figure out which combination works best for kids. **You may be eligible if...** - Your child is between 8 and 17 years old - Your child has experienced at least one traumatic event and meets the diagnostic criteria for PTSD - You are the caregiver with legal custody and can provide parental permission - Your child and family are willing to participate in therapy and complete surveys - Your child can read and understand English - Your child is in a stable home environment - If your child takes psychiatric medication, the dose has not changed in the past 2 months - You and/or your child have a smartphone that can download an app **You may NOT be eligible if...** - Your child does not meet PTSD diagnostic criteria - Your child is not in a stable living situation or a change is expected soon - You are not able to participate in treatment sessions Talk to your doctor to see if this trial is right for you.