Desmond DM, Maclachlan M Prevalence and characteristics of phantom limb pain and residual limb pain in the long term after upper limb amputation. Int J Rehabil Res. 2010 Sep;33(3):279-82. doi: 10.1097/MRR.0b013e328336388d.
Richardson C, Glenn S, Horgan M, Nurmikko T A prospective study of factors associated with the presence of phantom limb pain six months after major lower limb amputation in patients with peripheral vascular disease. J Pain. 2007 Oct;8(10):793-801. doi: 10.1016/j.jpain.2007.05.007. Epub 2007 Jul 12. Erratum In: J Pain. 2007 Dec;8(12):998.
Richardson C, Glenn S, Nurmikko T, Horgan M Incidence of phantom phenomena including phantom limb pain 6 months after major lower limb amputation in patients with peripheral vascular disease. Clin J Pain. 2006 May;22(4):353-8. doi: 10.1097/01.ajp.0000177
Yin Y, Zhang L, Xiao H, Wen CB, Dai YE, Yang G, Zuo YX, Liu J The pre-amputation pain and the postoperative deafferentation are the risk factors of phantom limb pain: a clinical survey in a sample of Chinese population. BMC Anesthesiol. 2017 May 26;17(1):69. doi: 10.1186/s12871-017-0359-6.
Sciatic Block in Contralateral Limb for Treatment of Refractory Phantom and Residual Limb Pain; a Triple-Blind Randomized Crossover Controlled Trial
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.
