1 - (SYM 27) Treatment of PTSD in the Military Health System: Which Patients Receive Evidence Based Psychotherapy?

Reach of psychotherapy is defined both by the proportion of potential beneficiaries who receive the intervention and by inequities in who does and does not receive treatment. Service members diagnosed with PTSD who receive an EBP may not represent all service members who could benefit from such treatments. Information on which patients initiate an EBP or receive a minimally adequate dosage of an EBP can inform efforts to increase the reach of EBPs in the Military Health System (MHS, e.g., targeted outreach efforts, provider training on contraindications to EBPs). The goal of the current study was to identify administrative, demographic, and clinical characteristics associated with receiving an EBP for PTSD. Among N=3,459 patients (26,429 psychotherapy encounters over ~4 years), 51% received any EBP sessions, 26% received 3 or more EBP sessions within 90 days, and 6% received 8 EBP sessions within 14 weeks. Machine learning models predicting each of these dose variables found that total number of sessions received, service branch, and mood disorder were predictors common to all three models. To our knowledge, this is the most comprehensive examination of EBP use in the MHS to date and the first to examine predictors of EBP use in the MHS. Findings highlight that the probability of receiving an EBP is higher when there is provider-patient capacity for regular sessions, within certain military branches, and in the absence of comorbid mood disorders.