Traumatic and chronic mental health problems have heightened the socio-economic cost, inducing military-civil collaboration. Since the military-civilian partnership offers conceptual development and technological development, we explored the partner-selection process in the military-civil strategic alliance for therapeutic products. Following the institutional approach, we applied legitimacy to the organisational and technological levels. First, we proposed that the military-civilian collaboration stands for the organisation's legitimacy (experience in the field). Second, we proposed the military-civilian collaboration predicts technological legitimacy (drugs versus psychotherapies).

We used a worldwide clinical trial dataset (10,585 projects) on military-civilian cooperation in mental health projects, comprising clinical trials for all types of therapies for mental health management. Especially, PTSD, stress and anxiety were the main concepts in the conditions of the sampled clinical trials since the National Institutes of Health (NIH) in the USA began to maintain the database from 1997 onwards.

For the legitimacy of the partner, we find support for the legitimacy of the organisation in the military-civilian partner selection. The military selects partners with an extensive portfolio of completed projects in the field. For the product's legitimacy, contrary to expectations, we find that mental health problems use psychotherapies more than drug therapies. Drug therapy has institutional support and higher legitimacy; psychotherapy is higher in the frequency of usage.

The theoretical and practical role of inter-organisational legitimacy and inter-project (inter-technology) legitimacy suggest that the sponsor's prestige is more important than the technological prestige.