Calderwood AH, Jacobson BC Comprehensive validation of the Boston Bowel Preparation Scale. Gastrointest Endosc. 2010 Oct;72(4):686-92. doi: 10.1016/j.gie.2010.06.068.
Matro R, Tupchong K, Daskalakis C, Gordon V, Katz L, Kastenberg D The effect on colon visualization during colonoscopy of the addition of simethicone to polyethylene glycol-electrolyte solution: a randomized single-blind study. Clin Transl Gastroenterol. 2012 Nov 29;3:e26. doi: 10.1038/ctg.2012.16.
Moraveji S, Casner N, Bashashati M, Garcia C, Dwivedi A, Zuckerman MJ, Carrion A, Ladd AM The role of oral simethicone on the adenoma detection rate and other quality indicators of screening colonoscopy: a randomized, controlled, observer-blinded clinical trial. Gastrointest Endosc. 2019 Jul;90(1):141-149. doi: 10.1016/j.gie.2019.03.018. Epub 2019 Mar 26.
Pan P, Zhao SB, Li BH, Meng QQ, Yao J, Wang D, Li ZS, Bai Y Effect of supplemental simethicone for bowel preparation on adenoma detection during colonoscopy: A meta-analysis of randomized controlled trials. J Gastroenterol Hepatol. 2019 Feb;34(2):314-320. doi: 10.1111/jgh.14401. Epub 2018 Aug 27.
Rostom A, Jolicoeur E Validation of a new scale for the assessment of bowel preparation quality. Gastrointest Endosc. 2004 Apr;59(4):482-6. Erratum in: Gastrointest Endosc. 2004 Aug;60(2):326.
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.
