Charles C, Gafni A, Whelan T Shared decision-making in the medical encounter: what does it mean? (or it takes at least two to tango). Soc Sci Med. 1997 Mar;44(5):681-92. doi: 10.1016/s0277-9536(96)00221-3.
Dowdy DW, Rodriguez RM, Hare CB, Kaplan B Cost-effectiveness of targeted human immunodeficiency virus screening in an urban emergency department. Acad Emerg Med. 2011 Jul;18(7):745-53. doi: 10.1111/j.1553-2712.2011.01110.x.
Durand MA, Carpenter L, Dolan H, Bravo P, Mann M, Bunn F, Elwyn G Do interventions designed to support shared decision-making reduce health inequalities? A systematic review and meta-analysis. PLoS One. 2014 Apr 15;9(4):e94670. doi: 10.1371/journal.pone.0094670. eCollection 2014.
Dye C, Glaziou P, Floyd K, Raviglione M Prospects for tuberculosis elimination. Annu Rev Public Health. 2013;34:271-86. doi: 10.1146/annurev-publhealth-031912-114431. Epub 2012 Dec 14.
Marseille E, Larson B, Kazi DS, Kahn JG, Rosen S Thresholds for the cost-effectiveness of interventions: alternative approaches. Bull World Health Organ. 2015 Feb 1;93(2):118-24. doi: 10.2471/BLT.14.138206. Epub 2014 Dec 15.
Menzies NA, Cohen T, Lin HH, Murray M, Salomon JA Population health impact and cost-effectiveness of tuberculosis diagnosis with Xpert MTB/RIF: a dynamic simulation and economic evaluation. PLoS Med. 2012;9(11):e1001347. doi: 10.1371/journal.pmed.1001347. Epub 2012 Nov 20.
Sandelowski M, Leeman J Writing usable qualitative health research findings. Qual Health Res. 2012 Oct;22(10):1404-13. doi: 10.1177/1049732312450368. Epub 2012 Jun 28.
Sandelowski MJ Justifying qualitative research. Res Nurs Health. 2008 Jun;31(3):193-5. doi: 10.1002/nur.20272. No abstract available.
Spiegelman D, Hertzmark E Easy SAS calculations for risk or prevalence ratios and differences. Am J Epidemiol. 2005 Aug 1;162(3):199-200. doi: 10.1093/aje/kwi188. Epub 2005 Jun 29. No abstract available.
Voils CI, Sandelowski M, Barroso J, Hasselblad V Making Sense of Qualitative and Quantitative Findings in Mixed Research Synthesis Studies. Field methods. 2008;20(1):3-25. doi: 10.1177/1525822X07307463.
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.