Gor N, Salem SB, Jakate S, Patel R, Shah N, Patil A Histological adequacy of EUS-guided liver biopsy when using a 19-gauge non-Tru-Cut FNA needle. Gastrointest Endosc. 2014 Jan;79(1):170-2. doi: 10.1016/j.gie.2013.06.031. Epub 2013 Jul 31.
Lee WJ, Uradomo LT, Zhang Y, Twaddell W, Darwin P Comparison of the Diagnostic Yield of EUS Needles for Liver Biopsy: Ex Vivo Study. Diagn Ther Endosc. 2017;2017:1497831. doi: 10.1155/2017/1497831. Epub 2017 Sep 13.
Rombaoa C CA Mo1351 The safety and feasibileity of endoscopic ultrasound-guided parenchymal liver biopsy at a large community hospital. Gastrointestinal endoscopy; 87(6): AB458.
Schulman AR, Thompson CC, Odze R, Chan WW, Ryou M Optimizing EUS-guided liver biopsy sampling: comprehensive assessment of needle types and tissue acquisition techniques. Gastrointest Endosc. 2017 Feb;85(2):419-426. doi: 10.1016/j.gie.2016.07.065. Epub 2016 Aug 13.
Sey MS, Al-Haddad M, Imperiale TF, McGreevy K, Lin J, DeWitt JM EUS-guided liver biopsy for parenchymal disease: a comparison of diagnostic yield between two core biopsy needles. Gastrointest Endosc. 2016 Feb;83(2):347-52. doi: 10.1016/j.gie.2015.08.012. Epub 2015 Aug 13.
Shah ND, Sasatomi E, Baron TH Endoscopic Ultrasound-guided Parenchymal Liver Biopsy: Single Center Experience of a New Dedicated Core Needle. Clin Gastroenterol Hepatol. 2017 May;15(5):784-786. doi: 10.1016/j.cgh.2017.01.011. Epub 2017 Jan 23.
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.
