most effective treatment or intervention for reducing the risk of developing depression or dying by suicide associated with living at high altitude. (2) Report Not later than 150 days after completing the study conducted under paragraph (1), the Secretary shall submit to the Committee on Veterans’ Affairs of the Senate and the Committee on Veterans’ Affairs of the House of Representatives a report on the results of the study. 303. Establishment by Department of Veterans Affairs and Department of Defense of clinical practice guidelines for comorbid mental health conditions (a) In general Not later than two years after the date of the enactment of this Act, the Secretary of Veterans Affairs, in consultation with the Secretary of Defense and the Secretary of Health and Human Services, shall complete the development of clinical practice guidelines for the treatment of post-traumatic stress disorder, military sexual trauma, and traumatic brain injury that is comorbid with substance use disorder or chronic pain. (b) Work group (1) Establishment In carrying out subsection (a), the Secretary of Veterans Affairs, the Secretary of Defense, and the Secretary of Health and Human Services shall create a Trauma and Comorbid Substance Use Disorder or Chronic Pain Work Group (in this section referred to as the Work Group ). (2) Membership The work group created under paragraph (1) shall be comprised of individuals that represent Federal Government entities and non-Federal Government entities with expertise in the areas covered by the work group, including the following: (A) Academic institutions that specialize in research for the treatment of conditions described in subsection (a). (B) The National Center for Posttraumatic Stress Disorder of the Department of Veterans Affairs. (C) The Office of the Assistant Secretary for Mental Health and Substance Use of the Department of Health and Human Services. (3) Relation to other work groups The Work Group shall be created and conducted in the same manner as other work groups for the