Miles SH, Koepp R, Weber EP Advance end-of-life treatment planning. A research review. Arch Intern Med. 1996 May 27;156(10):1062-8. Review.
Molina J, Pérez M, Herreros B, Martín MD, Velasco M [Knowledge and attitude regarding previous instructions for the patients of a public hospital of Madrid]. Rev Clin Esp. 2011 Oct;211(9):450-4. doi: 10.1016/j.rce.2011.06.007. Epub 2011 Aug 2. Spanish.
Pérez M, Herreros B, Martín MD, Molina J, Guijarro C, Velasco M [Changes in knowledge and carrying out the advance directives of patients admitted to internal medicine]. Rev Calid Asist. 2013 Sep-Oct;28(5):307-12. doi: 10.1016/j.cali.2013.03.008. Epub 20
Pérez M, Herreros B, Martín MD, Molina J, Kanouzi J, Velasco M Do Spanish Hospital Professionals Educate Their Patients About Advance Directives? : A Descriptive Study in a University Hospital in Madrid, Spain. J Bioeth Inq. 2016 Jun;13(2):295-303. doi:
Evaluating the Efficacy of an Advanced Care Planning Program for Health Decisions in Patients With Advanced Heart Failure
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.