Subgroup analyses in randomised controlled trials: cohort study on trial protocols and journal publications

Kasenda, Benjamin and Schandelmaier, Stefan and Sun, Xin and von Elm, Erik and You, John and Blümle, Anette and Tomonaga, Yuki and Saccilotto, Ramon and Amstutz, Alain and Bengough, Theresa and Meerpohl, Joerg J. and Stegert, Mihaela and Olu, Kelechi K. and Tikkinen, Kari A. O. and Neumann, Ignacio and Carrasco-Labra, Alonso and Faulhaber, Markus and Mulla, Sohail M. and Mertz, Dominik and Akl, Elie A. and Bassler, Dirk and Busse, Jason W. and Ferreira-González, Ignacio and Lamontagne, Francois and Nordmann, Alain and Gloy, Viktoria and Raatz, Heike and Moja, Lorenzo and Rosenthal, Rachel and Ebrahim, Shanil and Vandvik, Per O. and Johnston, Bradley C. and Walter, Martin A. and Burnand, Bernard and Schwenkglenks, Matthias and Hemkens, Lars G. and Bucher, Heiner C. and Guyatt, Gordon H. and Briel, Matthias and Disco Study Group, . (2014) Subgroup analyses in randomised controlled trials: cohort study on trial protocols and journal publications. BMJ, 349. g4539.

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Official URL: http://edoc.unibas.ch/53537/

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To investigate the planning of subgroup analyses in protocols of randomised controlled trials and the agreement with corresponding full journal publications.; Cohort of protocols of randomised controlled trial and subsequent full journal publications.; Six research ethics committees in Switzerland, Germany, and Canada.; 894 protocols of randomised controlled trial involving patients approved by participating research ethics committees between 2000 and 2003 and 515 subsequent full journal publications.; Of 894 protocols of randomised controlled trials, 252 (28.2%) included one or more planned subgroup analyses. Of those, 17 (6.7%) provided a clear hypothesis for at least one subgroup analysis, 10 (4.0%) anticipated the direction of a subgroup effect, and 87 (34.5%) planned a statistical test for interaction. Industry sponsored trials more often planned subgroup analyses compared with investigator sponsored trials (195/551 (35.4%) v 57/343 (16.6%), P<0.001). Of 515 identified journal publications, 246 (47.8%) reported at least one subgroup analysis. In 81 (32.9%) of the 246 publications reporting subgroup analyses, authors stated that subgroup analyses were prespecified, but this was not supported by 28 (34.6%) corresponding protocols. In 86 publications, authors claimed a subgroup effect, but only 36 (41.9%) corresponding protocols reported a planned subgroup analysis.; Subgroup analyses are insufficiently described in the protocols of randomised controlled trials submitted to research ethics committees, and investigators rarely specify the anticipated direction of subgroup effects. More than one third of statements in publications of randomised controlled trials about subgroup prespecification had no documentation in the corresponding protocols. Definitive judgments regarding credibility of claimed subgroup effects are not possible without access to protocols and analysis plans of randomised controlled trials.
Faculties and Departments:03 Faculty of Medicine > Departement Klinische Forschung > Clinical Epidemiology and Biostatistics CEB > Klinische Epidemiologie (Bucher H)
UniBasel Contributors:Kasenda, Benjamin
Item Type:Article, refereed
Article Subtype:Research Article
Publisher:BMJ Publishing Group
Note:Publication type according to Uni Basel Research Database: Journal article
Identification Number:
Last Modified:26 Oct 2017 14:59
Deposited On:26 Oct 2017 14:59

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