Burt RW Strategies for colon cancer screening with considerations of cost and access to care. J Natl Compr Canc Netw. 2010 Jan;8(1):2-5.
Centers for Disease Control and Prevention (CDC) Vital signs: colorectal cancer screening among adults aged 50-75 years - United States, 2008. MMWR Morb Mortal Wkly Rep. 2010 Jul 9;59(26):808-12.
Greiner KA, Born W, Nollen N, Ahluwalia JS Knowledge and perceptions of colorectal cancer screening among urban African Americans. J Gen Intern Med. 2005 Nov;20(11):977-83.
Lasser KE, Ayanian JZ, Fletcher RH, Good MJ Barriers to colorectal cancer screening in community health centers: a qualitative study. BMC Fam Pract. 2008 Feb 27;9:15. doi: 10.1186/1471-2296-9-15.
Zapka J Innovative provider- and health system-directed approaches to improving colorectal cancer screening delivery. Med Care. 2008 Sep;46(9 Suppl 1):S62-7. doi: 10.1097/MLR.0b013e31817fdf57.
Health Literacy Interventions to Overcome Disparities in CRC Screening
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.