Detering KM, Hancock AD, Reade MC, Silvester W The impact of advance care planning on end of life care in elderly patients: randomised controlled trial. BMJ. 2010 Mar 23;340:c1345. doi: 10.1136/bmj.c1345.
Fried TR, Redding CA, Robbins ML, O'Leary JR, Iannone L Agreement between older persons and their surrogate decision-makers regarding participation in advance care planning. J Am Geriatr Soc. 2011 Jun;59(6):1105-9. doi: 10.1111/j.1532-5415.2011.03412.x.
Heyland DK, Ilan R, Jiang X, You JJ, Dodek P The prevalence of medical error related to end-of-life communication in Canadian hospitals: results of a multicentre observational study. BMJ Qual Saf. 2016 Sep;25(9):671-9. doi: 10.1136/bmjqs-2015-004567. Epu
Johnston SC, Pfeifer MP, McNutt R The discussion about advance directives. Patient and physician opinions regarding when and how it should be conducted. End of Life Study Group. Arch Intern Med. 1995 May 22;155(10):1025-30.
Rhee JJ, Zwar NA, Kemp LA Advance care planning and interpersonal relationships: a two-way street. Fam Pract. 2013 Apr;30(2):219-26. doi: 10.1093/fampra/cms063. Epub 2012 Oct 1.
Silveira MJ, Kim SY, Langa KM Advance directives and outcomes of surrogate decision making before death. N Engl J Med. 2010 Apr 1;362(13):1211-8. doi: 10.1056/NEJMsa0907901.
Teno JM, Fisher ES, Hamel MB, Coppola K, Dawson NV Medical care inconsistent with patients' treatment goals: association with 1-year Medicare resource use and survival. J Am Geriatr Soc. 2002 Mar;50(3):496-500.
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.