Burrows GD, Norman TR, Judd FK Definition and differential diagnosis of treatment-resistant depression. Int Clin Psychopharmacol. 1994 Jun;9 Suppl 2:5-10. Review.
Correll GE, Futter GE Two case studies of patients with major depressive disorder given low-dose (subanesthetic) ketamine infusions. Pain Med. 2006 Jan-Feb;7(1):92-5.
Correll GE, Maleki J, Gracely EJ, Muir JJ, Harbut RE Subanesthetic ketamine infusion therapy: a retrospective analysis of a novel therapeutic approach to complex regional pain syndrome. Pain Med. 2004 Sep;5(3):263-75.
First MB, Spitzer RL, Miriam G, Williams JBW Structured Clinical Interview for DSM-IV-TR Axis I Disorders, Research Version, Patient Edition. (SCID-I/P). New York: Biometrics Research, New York State Psychiatric Institute; 2002
HAMILTON M A rating scale for depression. J Neurol Neurosurg Psychiatry. 1960 Feb;23:56-62.
Hirota K, Lambert DG Ketamine: its mechanism(s) of action and unusual clinical uses. Br J Anaesth. 1996 Oct;77(4):441-4.
Kudoh A, Takahira Y, Katagai H, Takazawa T Small-dose ketamine improves the postoperative state of depressed patients. Anesth Analg. 2002 Jul;95(1):114-8, table of contents.
Leonard B Clinical implications of mechaniszms of action of antidepresants. Advan Psychiatr Treat. 2000;6:178-186.
Overall J, Gorham D The brief psychiatric rating scale. Psycol Rep. 1962;10:799-812.
Paul IA, Skolnick P Glutamate and depression: clinical and preclinical studies. Ann N Y Acad Sci. 2003 Nov;1003:250-72. Review.
Pincus HA, Pettit AR The societal costs of chronic major depression. J Clin Psychiatry. 2001;62 Suppl 6:5-9. Review.
Sackeim HA The definition and meaning of treatment-resistant depression. J Clin Psychiatry. 2001;62 Suppl 16:10-17. Burrows GD, Norman TR, Judd FK. Definition and differential diagnosis of treatment-resistant depression. Int Clin Psychopharmacol. Jun 1994;9 Suppl 2:5-10.
Stewart CE Ketamine as a street drug. Emerg Med Serv. 2001 Nov;30(11):30, 32, 34 passim. Review.
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.