K S Gurusamy1, C Gluud, D Nikolova, B R Davidson. 1. University Department of Surgery, Royal Free Hospital and University College School of Medicine, London, UK. kurinchi2k@hotmail.com
Abstract
BACKGROUND: Meta-analysis of randomized clinical trials (RCTs) with low risk of bias is considered the highest level of evidence available for evaluating an intervention. Bias in RCTs may overestimate or underestimate the true effectiveness of an intervention. METHODS: The causes of bias in surgical trials as described by The Cochrane Collaboration, and the methods that can be used to avoid them, are reviewed. RESULTS: Blinding is difficult in many surgical trials but careful trial design can reduce the bias risk due to lack of blinding. It is possible to conduct surgical trials with low risk of bias by using appropriate trial design. CONCLUSION: The risk of providing a treatment based on a biased effect estimate must be balanced against the difficulty of conducting trials with very low risk of bias. Better understanding of the risk of bias may result in improved trials with a closer estimate of the true effectiveness of an intervention. (c) 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.
BACKGROUND: Meta-analysis of randomized clinical trials (RCTs) with low risk of bias is considered the highest level of evidence available for evaluating an intervention. Bias in RCTs may overestimate or underestimate the true effectiveness of an intervention. METHODS: The causes of bias in surgical trials as described by The Cochrane Collaboration, and the methods that can be used to avoid them, are reviewed. RESULTS: Blinding is difficult in many surgical trials but careful trial design can reduce the bias risk due to lack of blinding. It is possible to conduct surgical trials with low risk of bias by using appropriate trial design. CONCLUSION: The risk of providing a treatment based on a biased effect estimate must be balanced against the difficulty of conducting trials with very low risk of bias. Better understanding of the risk of bias may result in improved trials with a closer estimate of the true effectiveness of an intervention. (c) 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.
Authors: Edmund A M Neugebauer; Monika Becker; Gerhard F Buess; Alfred Cuschieri; Hans-Peter Dauben; Abe Fingerhut; Karl H Fuchs; Brigitte Habermalz; Leonid Lantsberg; Mario Morino; Stella Reiter-Theil; Gabriela Soskuty; Wolfgang Wayand; Thilo Welsch Journal: Surg Endosc Date: 2010-01-07 Impact factor: 4.584
Authors: Mahmoud Abu-Amara; Kurinchi Selvan Gurusamy; George Glantzounis; Barry Fuller; Brian R Davidson Journal: Cochrane Database Syst Rev Date: 2009-10-07
Authors: Giuseppe Fede; Giacomo Germani; Christian Gluud; Kurinchi Selvan Gurusamy; Andrew K Burroughs Journal: Cochrane Database Syst Rev Date: 2011-06-15
Authors: Bobby V M Dasari; Chuan Jin Tan; Kurinchi Selvan Gurusamy; David J Martin; Gareth Kirk; Lloyd McKie; Tom Diamond; Mark A Taylor Journal: Cochrane Database Syst Rev Date: 2013-12-12