Dindo D, Demartines N, Clavien PA Classification of surgical complications: a new proposal with evaluation in a cohort of 6336 patients and results of a survey. Ann Surg. 2004 Aug;240(2):205-13.
Kehlet H, Wilmore DW Multimodal strategies to improve surgical outcome. Am J Surg. 2002 Jun;183(6):630-41. Review.
Lee TG, Kang SB, Kim DW, Hong S, Heo SC, Park KJ Comparison of early mobilization and diet rehabilitation program with conventional care after laparoscopic colon surgery: a prospective randomized controlled trial. Dis Colon Rectum. 2011 Jan;54(1):21-8. doi: 10.1007/DCR.0b013e3181fcdb3e.
Ljungqvist O, Scott M, Fearon KC Enhanced Recovery After Surgery: A Review. JAMA Surg. 2017 Mar 1;152(3):292-298. doi: 10.1001/jamasurg.2016.4952. Review.
Wang Q, Suo J, Jiang J, Wang C, Zhao YQ, Cao X Effectiveness of fast-track rehabilitation vs conventional care in laparoscopic colorectal resection for elderly patients: a randomized trial. Colorectal Dis. 2012 Aug;14(8):1009-13. doi: 10.1111/j.1463-1318.2011.02855.x.
Wilmore DW, Kehlet H Management of patients in fast track surgery. BMJ. 2001 Feb 24;322(7284):473-6. Review.
Zaouter C, Kaneva P, Carli F Less urinary tract infection by earlier removal of bladder catheter in surgical patients receiving thoracic epidural analgesia. Reg Anesth Pain Med. 2009 Nov-Dec;34(6):542-8.
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.