Imperial College London
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ProfessorDeborahAshby

Faculty of Medicine, School of Public Health

Dean of the Faculty of Medicine
 
 
 
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Contact

 

+44 (0)20 7594 8704deborah.ashby Website

 
 
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Location

 

2.15Faculty BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Cook:2018:10.1186/s13063-018-2884-0,
author = {Cook, JA and Julious, SA and Sones, W and Hampson, LV and Hewitt, C and Berlin, JA and Ashby, D and Emsley, R and Fergusson, DA and Walters, SJ and Wilson, ECF and Maclennan, G and Stallard, N and Rothwell, JC and Bland, M and Brown, L and Ramsay, CR and Cook, A and Armstrong, D and Altman, D and Vale, LD},
doi = {10.1186/s13063-018-2884-0},
journal = {Trials},
title = {DELTA(2) guidance on choosing the target difference and undertaking and reporting the sample size calculation for a randomised controlled trial},
url = {http://dx.doi.org/10.1186/s13063-018-2884-0},
volume = {19},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - BackgroundA key step in the design of a RCT is the estimation of the number of participants needed in the study. The most common approach is to specify a target difference between the treatments for the primary outcome and then calculate the required sample size. The sample size is chosen to ensure that the trial will have a high probability (adequate statistical power) of detecting a target difference between the treatments should one exist.The sample size has many implications for the conduct and interpretation of the study. Despite the critical role that the target difference has in the design of a RCT, the way in which it is determined has received little attention. In this article, we summarise the key considerations and messages from new guidance for researchers and funders on specifying the target difference, and undertaking and reporting a RCT sample size calculation. This article on choosing the target difference for a randomised controlled trial (RCT) and undertaking and reporting the sample size calculation has been dual published in the BMJ and BMC Trials journalsMethodsThe DELTA2 (Difference ELicitation in TriAls) project comprised five major components: systematic literature reviews of recent methodological developments (stage 1) and existing funder guidance (stage 2); a Delphi study (stage 3); a two-day consensus meeting bringing together researchers, funders and patient representatives (stage 4); and the preparation and dissemination of a guidance document (stage 5).Results and DiscussionThe key messages from the DELTA2 guidance on determining the target difference and sample size calculation for a randomised caontrolled trial are presented. Recommendations for the subsequent reporting of the sample size calculation are also provided.
AU  - Cook,JA
AU  - Julious,SA
AU  - Sones,W
AU  - Hampson,LV
AU  - Hewitt,C
AU  - Berlin,JA
AU  - Ashby,D
AU  - Emsley,R
AU  - Fergusson,DA
AU  - Walters,SJ
AU  - Wilson,ECF
AU  - Maclennan,G
AU  - Stallard,N
AU  - Rothwell,JC
AU  - Bland,M
AU  - Brown,L
AU  - Ramsay,CR
AU  - Cook,A
AU  - Armstrong,D
AU  - Altman,D
AU  - Vale,LD
DO  - 10.1186/s13063-018-2884-0
PY  - 2018///
SN  - 1745-6215
TI  - DELTA(2) guidance on choosing the target difference and undertaking and reporting the sample size calculation for a randomised controlled trial
T2  - Trials
UR  - http://dx.doi.org/10.1186/s13063-018-2884-0
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000449480500001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - http://hdl.handle.net/10044/1/64470
VL  - 19
ER  -
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