Abstract:
Objectives
To find evidence, either corroborating or refuting, for many persisting beliefs regarding the feasibility of carrying out surgical randomised controlled trials with a placebo arm, with emphasis on the challenges related to recruitment, funding, anaesthesia or blinding.
Design
Systematic review.
Data sources and study selection
The analysis involved studies published between 1959 and 2014 that were identified during an earlier systematic review of benefits and harms of placebo-controlled surgical trials published in 2014.
Results
63 trials were included in the review. The main problem reported in many trials was a very slow recruitment rate, mainly due to the difficulty in finding eligible patients. Existing placebo trials were funded equally often from commercial and non-commercial sources. General anaesthesia or sedation was used in 41% of studies. Among the reviewed trials, 81% were double-blinded, and 19% were single-blinded. Across the reviewed trials, 96% (range 50–100%) of randomised patients completed the study. The withdrawal rate during the study was similar in the surgical and in the placebo groups.
Conclusions
This review demonstrated that placebo-controlled surgical trials are feasible, at least for procedures with a lower level of invasiveness, but also that recruitment is difficult. Many of the presumed challenges to undertaking such trials, for example, funding, anaesthesia or blinding of patients and assessors, were not reported as obstacles to completion in any of the reviewed trials.
Citation: Karolina Wartolowska, Gary S Collins, Sally Hopewell, Andrew Judge, Benjamin J F Dean, Ines Rombach, David J Beard, Andrew J Carr Feasibility Of Surgical Randomised Controlled Trials With A Placebo Arm: A Systematic Review BMJ Open 2016;6:e010194 doi:10.1136/bmjopen-2015-010194
Received 6 October 2015 Revised 19 January 2016 Accepted 15 February 2016 Published 15 March 2016
Copyright: This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY 4.0) license, which permits others to distribute, remix, adapt and build upon this work, for commercial use, provided the original work is properly cited.
Contributors
KW contributed to study concept and design. KW, AJ, SH and GSC contributed to design of the search strategy and statistical analysis. KW, IR and BJFD contributed to data collection and management. KW contributed to drafting of the manuscript and the guarantor of the study. KW, AJC, DJB, IR, BJFD, SH and GSC contributed to critical revision of the manuscript for important intellectual content. All authors had full access to all of the data in the study and can take responsibility for the integrity of the data and the accuracy of the data analysis. All authors revised and approved the final version of the article.
Funding
The study was funded by the National Institute of Health Research Oxford Musculoskeletal Biomedical Research Unit.
Competing interests
The authors are involved in a placebo-controlled surgical trial on shoulder pain (NCT01623011).
