Randomization is not the (Only) Answer: A Plea for Structured Objective Evaluation of Endoscopic Therapy

Endoscopic therapy clearly has a primary role in many clinical conditions (such as dysphagia, obstructive jaundice, bleeding, and colonic polyps). There is much less certainty about the role of endoscopy in many other clinical contexts (e. g. management of chronic pancreatitis). Randomization is the gold standard for evaluation of competing therapies. Unfortunately, there are many difficulties in mounting meaningful randomized controlled trials of endoscopic methods. Many have been done, but few have provided us with real practical answers. This article argues that the evidence we need to advise patients is often better obtained through very stringent observational studies, provided that all necessary data elements are defined and documented and independent objective arbiters (referees) are fully involved in the process.

References

• 1 Cotton P B. Therapeutic gastrointestinal endoscopy. Problems in proving efficacy.  N Engl J Med. 1992;  326 1626-1628
• 2 Cotton P B. Outcomes of endoscopy procedures: struggling towards definitions.  Gastrointest Endosc. 1994;  40 514-518
• 3 Cotton P B. Endoscopy in crisis. The challenge of new technology.  Gastrointest Endosc. 1997;  46 189-191
• 4 Smith A C, Dowsett J F, Russell R CG, et al. Randomised trial of endoscopic stenting versus surgical bypass in malignant low bile duct obstruction.  Lancet. 1994;  344 1655-1660
• 5 McDermott W M, Amorosino C S. Sounding board of mice but not men.  N Engl J Med. 1991;  324 1585-1589
• 6 Passamani E. Clinical trials - are they ethical?.  N Engl J Med. 1991;  324 1589-1592
• 7 Pollock A V. Surgical evaluation at the crossroads.  Br J Surg. 1993;  80 964-966
• 8 Lans J I, Geenen J E, Johanson J F, et al. Endoscopic therapy in patients with pancreas divisum and acute pancreatitis: a prospective, randomized, controlled clinical trial.  Gastrointest Endosc. 1992;  38 430-434
• 9 Warshaw A L, Banks P A, Fernandez-del Castillo C. AGA technical review on treatment of pain in chronic pancreatitis.  Gastroenterology. 1998;  115 763-764
• 10 Cotton P B, Jowell P S, Baillie J, et al. Spectrum of complications after diagnostic ERCP and effect of comorbidities.  Gastrointest Endosc. 1994;  40 (2) A16
• 11 Keat A S. The ASA classification of physical status: a recapitulation.  Anesthesiology. 1978;  49 233-237
• 12 Iezzoni L I, Ash A S, Shwartz M, et al. Predicting who dies depends on how severity is measured: implications for evaluation patient outcomes.  Ann Int Med. 1995;  123 763-770
• 13 Thomas J W, Ashcraft M LF. Measuring severity of illness: six severity systems and their ability to explain cost variations.  Inquiry. 1991;  28 39-55
• 14 Charlson M E, Pompei P, Ales K L, Mackenzie C R. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation.  J Chron Dis. 1987;  40 373-383
• 15 Cotton P B, Schmitt C. Quality of life in palliative management of malignant obstructive jaundice.  Scand J Gastroenterol. 1993;  28 Suppl. 199 44-46
• 16 Ware J E, Sherborne C D. The MOS 36-item short-form health survey (SF-36): I. Conceptual framework and item selection.  Med Care. 1992;  30 473-483
• 17 Eypasch E, Williams J I, Wood-Dauphinee S, et al. Gastrointestinal quality of life index: development, validation and application of a new instrument.  Br J Surg. 1995;  82 216-222
• 18 Palesch Y Y, Herbert R L, Tarnasky P R, et al. DDQ-15: A health-related quality of life instrument for patients with digestive disorders. Amer J Gastro Submitted 1999
• 19 Irvine E J, Feagan B, Rochon J, et al. Quality of life: a valid and reliable measure of therapeutic efficacy in the treatment of inflammatory bowel disease.  Gastroenterology. 1994;  106 287-296