Hermann LK, Weingart SD, Duvall WL, Henzlova MJ The limited utility of routine cardiac stress testing in emergency department chest pain patients younger than 40 years. Ann Emerg Med. 2009 Jul;54(1):12-6. doi: 10.1016/j.annemergmed.2009.01.006. Epub 2009 Feb 23.
Hollander JE, Sites FD, Pollack CV Jr, Shofer FS Lack of utility of telemetry monitoring for identification of cardiac death and life-threatening ventricular dysrhythmias in low-risk patients with chest pain. Ann Emerg Med. 2004 Jan;43(1):71-6.
O'Neill DR Low-risk classified chest pain patients: Do they need cardiac monitoring in the emergency department and can they be cared for in non-monitored beds? Australian Emerg Nur J 2007; 10:58-63.
Perkins J, McCurdy MT, Vilke GM, Al-Marshad AA Telemetry bed usage for patients with low-risk chest pain: review of the literature for the clinician. J Emerg Med. 2014 Feb;46(2):273-7. doi: 10.1016/j.jemermed.2013.08.098. Epub 2013 Nov 22. 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.
