This is an exploratory qualitative interview study being conducted with a primary objective of examining perceptions held by active military and veterans regarding help-seeking attitudes and mental health beliefs which influence the decision to consent or decline participation in Post-Traumatic Stress Disorder (PTSD) or Traumatic Brain Injury (TBI) clinical trials. Active duty military and/or veterans aged 18 years and older who consent to participate (N = 50), or have recently declined participation (N = 50), in an INTRuST affiliated outpatient clinical trial for deployment-related PTSD or TBI will be recruited. Participants who consent to participate in an INTRuST clinical trial (Group 1) will be interviewed once at the beginning the of the clinical trial, and again following participation in the trial. Participants who decline participation in an INTRuST affiliated outpatient clinical trial (Group 2) will be interviewed once. For participants in both groups, study participation will initiate within 1 month of referral to study. Total duration of study participation is based on the specific clinical trial that the participant is recruitment from; the longest trial is estimated to be 24 weeks or less. Semi-structured qualitative individual interviews will be conducted to carry out a thematic analysis of the data exploring familial, social and institution-level constructs which may influence the subjective experience of the research treatment process.

Inclusion Criteria:

1. Age between 18 and over
2. Active duty and/or veteran
3. Referred to participate in INTRuST-affiliated outpatient clinical trials for PTSD or TBI
4. Ability to provide written informed consent

Active military and/or veterans ages 18 or over who have recently considered participating in an outpatient clinical trial for PTSD or TBI.