Bernstein CN, Blanchard JF, Rawsthorne P, Yu N The prevalence of extraintestinal diseases in inflammatory bowel disease: a population-based study. Am J Gastroenterol. 2001 Apr;96(4):1116-22.
Haroon NN, Paterson JM, Li P, Inman RD, Haroon N Patients With Ankylosing Spondylitis Have Increased Cardiovascular and Cerebrovascular Mortality: A Population-Based Study. Ann Intern Med. 2015 Sep 15;163(6):409-16. doi: 10.7326/M14-2470.
Lichtenstein GR, Yan S, Bala M, Blank M, Sands BE Infliximab maintenance treatment reduces hospitalizations, surgeries, and procedures in fistulizing Crohn's disease. Gastroenterology. 2005 Apr;128(4):862-9.
Manasson J, Scher JU Spondyloarthritis and the microbiome: new insights from an ancient hypothesis. Curr Rheumatol Rep. 2015 Feb;17(2):10. doi: 10.1007/s11926-014-0487-7. Review.
Sieper J, van der Heijde D Review: Nonradiographic axial spondyloarthritis: new definition of an old disease? Arthritis Rheum. 2013 Mar;65(3):543-51. doi: 10.1002/art.37803. Review.
Subramaniam K, Tymms K, Shadbolt B, Pavli P Spondyloarthropathy in inflammatory bowel disease patients on TNF inhibitors. Intern Med J. 2015 Nov;45(11):1154-60. doi: 10.1111/imj.12891.
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.
