Engel CC, Hyams KC, Scott K Managing future Gulf War Syndromes: international lessons and new models of care. Philos Trans R Soc Lond B Biol Sci. 2006 Apr 29;361(1468):707-20.
Engel CC Improving primary care for military personnel and veterans with posttraumatic stress disorder--the road ahead. Gen Hosp Psychiatry. 2005 May-Jun;27(3):158-60.
Hoge CW, Auchterlonie JL, Milliken CS Mental health problems, use of mental health services, and attrition from military service after returning from deployment to Iraq or Afghanistan. JAMA. 2006 Mar 1;295(9):1023-32.
Lisa S Meredith, Terri L. Tanielian, Michael D. Greenberg, Ana Suárez, Elizabeth Eiseman. "Expanding Access to Mental Health Counselors: Evaluation of the Tricare Demonstration" RAND/DRR-3458-1-OSD (available at www.rand.org)
Litz BT, Engel CC, Bryant RA, Papa A A randomized, controlled proof-of-concept trial of an Internet-based, therapist-assisted self-management treatment for posttraumatic stress disorder. Am J Psychiatry. 2007 Nov;164(11):1676-83.
Spira, J L., Pyne, J.M., & Wiederhold, B. (2006). Chapter 10: Experiential Methods in the Treatment of Combat PTSD. In Figley, C.R. and Nash, W.P. In For Those Who Bore the Battle: Combat Stress Injury Theory, Research, and Management. For the Routledge Psychosocial Stress Book Series
Tanielian, T & Jaycox, L., Eds. "Invisible Wounds of War: Psychological and Cognitive Injuries, Their Consequences, and Services to Assist Recovery." RAND/MG-720- CCF (available at http://veterans.rand.org)
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.