Mace H, Lightfoot N, McCluskey S, Selby R, Roy D, Timoumi T, Karkouti K Validity of Thromboelastometry for Rapid Assessment of Fibrinogen Levels in Heparinized Samples During Cardiac Surgery: A Retrospective, Single-center, Observational Study. J Cardiothorac Vasc Anesth. 2016 Jan;30(1):90-5. doi: 10.1053/j.jvca.2015.04.030. Epub 2015 May 5.
Mallaiah S, Barclay P, Harrod I, Chevannes C, Bhalla A Introduction of an algorithm for ROTEM-guided fibrinogen concentrate administration in major obstetric haemorrhage. Anaesthesia. 2015 Feb;70(2):166-75. doi: 10.1111/anae.12859. Epub 2014 Oct 7. Erratum in: Anaesthesia. 2015 Nov;70(11):1334.
Pérez-Calatayud ÁA, Briones-Garduño JC, Rojas-Arellano ML [Use of thromboelastography and thromboelastometry for the rational and opportune transfusion of hemoderivatives in obstetric hemorrhage]. Ginecol Obstet Mex. 2015 Sep;83(9):569-77. Review. Spanis
Song JG, Jeong SM, Jun IG, Lee HM, Hwang GS Five-minute parameter of thromboelastometry is sufficient to detect thrombocytopenia and hypofibrinogenaemia in patients undergoing liver transplantation. Br J Anaesth. 2014 Feb;112(2):290-7. doi: 10.1093/bja/aet325. Epub 2013 Sep 24.
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.