Cukor D, Coplan J, Brown C, Peterson RA, Kimmel PL Course of depression and anxiety diagnosis in patients treated with hemodialysis: a 16-month follow-up. Clin J Am Soc Nephrol. 2008 Nov;3(6):1752-8. doi: 10.2215/CJN.01120308. Epub 2008 Aug 6.
Cukor D, Rosenthal DS, Jindal RM, Brown CD, Kimmel PL Depression is an important contributor to low medication adherence in hemodialyzed patients and transplant recipients. Kidney Int. 2009 Jun;75(11):1223-1229. doi: 10.1038/ki.2009.51. Epub 2009 Feb 25.
Davison SN, Jhangri GS The impact of chronic pain on depression, sleep, and the desire to withdraw from dialysis in hemodialysis patients. J Pain Symptom Manage. 2005 Nov;30(5):465-73.
Duarte PS, Miyazaki MC, Blay SL, Sesso R Cognitive-behavioral group therapy is an effective treatment for major depression in hemodialysis patients. Kidney Int. 2009 Aug;76(4):414-21. doi: 10.1038/ki.2009.156. Epub 2009 May 20.
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.