Faiz O, Brown T, Bottle A, Burns EM, Darzi AW, Aylin P Impact of hospital institutional volume on postoperative mortality after major emergency colorectal surgery in English National Health Service Trusts, 2001 to 2005. Dis Colon Rectum. 2010 Apr;53(4):393-401. doi: 10.1007/DCR.0b013e3181cc6fd2.
Faiz O, Haji A, Bottle A, Clark SK, Darzi AW, Aylin P Elective colonic surgery for cancer in the elderly: an investigation into postoperative mortality in English NHS hospitals between 1996 and 2007. Colorectal Dis. 2011 Jul;13(7):779-85. doi: 10.1111/j.1463-1318.2010.02290.x. Epub 2010 Apr 19.
Grocott MP, Pearse RM Prognostic studies of perioperative risk: robust methodology is needed. Br J Anaesth. 2010 Sep;105(3):243-5. doi: 10.1093/bja/aeq207.
Hennis PJ, Meale PM, Grocott MP Cardiopulmonary exercise testing for the evaluation of perioperative risk in non-cardiopulmonary surgery. Postgrad Med J. 2011 Aug;87(1030):550-7. doi: 10.1136/pgmj.2010.107185. Epub 2011 Jun 21. Review.
Jack S, West M, Grocott MP Perioperative exercise training in elderly subjects. Best Pract Res Clin Anaesthesiol. 2011 Sep;25(3):461-72. doi: 10.1016/j.bpa.2011.07.003. Review.
Robinson TN, Wu DS, Stiegmann GV, Moss M Frailty predicts increased hospital and six-month healthcare cost following colorectal surgery in older adults. Am J Surg. 2011 Nov;202(5):511-4. doi: 10.1016/j.amjsurg.2011.06.017. Epub 2011 Sep 3.
Sündermann S, Dademasch A, Rastan A, Praetorius J, Rodriguez H, Walther T, Mohr FW, Falk V One-year follow-up of patients undergoing elective cardiac surgery assessed with the Comprehensive Assessment of Frailty test and its simplified form. Interact Cardiovasc Thorac Surg. 2011 Aug;13(2):119-23; discussion 123. doi: 10.1510/icvts.2010.251884. Epub 2011 Mar 4.
Tan KY, Kawamura YJ, Tokomitsu A, Tang T Assessment for frailty is useful for predicting morbidity in elderly patients undergoing colorectal cancer resection whose comorbidities are already optimized. Am J Surg. 2012 Aug;204(2):139-43. doi: 10.1016/j.amjsurg.2011.08.012. Epub 2011 Dec 16.
Prospective Observational Study of Patients Aged >=60 Years Undergoing Major Gastrointestinal Surgery With 1 Year Follow-up
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.
