000340129 001__ 340129 000340129 005__ 20240228054314.0 000340129 022__ $$a1536-8634 000340129 0247_ $$2doi$$a10.22004/ag.econ.340129 000340129 037__ $$a199-2024-511 000340129 041__ $$aeng 000340129 245__ $$aReference-based sensitivity analysis via multiple imputation for longitudinal trials with protocol deviation 000340129 260__ $$c2016-04 000340129 269__ $$a2016-04 000340129 336__ $$aJournal Article 000340129 520__ $$aRandomized controlled trials provide essential evidence for the evaluation of new and existing medical treatments. Unfortunately, the statistical analysis is often complicated by the occurrence of protocol deviations, which mean we cannot always measure the intended outcomes for individuals who deviate, resulting in a missing-data problem. In such settings, however one approaches the analysis, an untestable assumption about the distribution of the unobserved data must be made. To understand how far the results depend on these assumptions, the primary analysis should be supplemented by a range of sensitivity analyses, which explore how the conclusions vary over a range of different credible assumptions for the missing data. In this article, we describe a new command, mimix, that can be used to perform reference-based sensitivity analyses for randomized controlled trials with longitudinal quantitative outcome data, using the approach proposed by Carpenter, Roger, and Kenward (2013, Journal of Biopharmaceutical Statistics 23: 1352–1371). Under this approach, we make qualitative assumptions about how individuals’ missing outcomes relate to those observed in relevant groups in the trial, based on plausible clinical scenarios. Statistical analysis then proceeds using the method of multiple imputation. 000340129 546__ $$aEnglish 000340129 6531_ $$ast0440 000340129 6531_ $$amimix 000340129 6531_ $$aclinical trial 000340129 6531_ $$aprotocol deviation 000340129 6531_ $$amissing data 000340129 6531_ $$amultiple imputation 000340129 6531_ $$asensitivity analysis 000340129 700__ $$aCro, Suzie 000340129 700__ $$aMorris, Tim P. 000340129 700__ $$aKenward, Michael G. 000340129 700__ $$aCarpenter, James R. 000340129 773__ $$j16$$k2$$q443$$o463$$tStata Journal 000340129 8560_ $$fbecke073@umn.edu 000340129 8564_ $$917e77499-40fe-40d0-bdbc-719a4819b46a$$s282236$$uhttps://ageconsearch.umn.edu/record/340129/files/Cro.pdf 000340129 909CO $$ooai:ageconsearch.umn.edu:340129$$pGLOBAL_SET 000340129 913__ $$aBy depositing this Content ('Content') in AgEcon Search, I agree that I am solely responsible for any consequences of uploading this Content to AgEcon Search and making it publicly available, and I represent and warrant that: I am either the sole creator and the owner of the copyrights and all other rights in the Content; or, without obtaining another’s permission, I have the right to deposit the Content in an archive such as AgEcon Search. To the extent that any portions of the Content are not my own creation, they are used with the copyright holder’s express permission or as permitted by law. Additionally, the Content does not infringe the copyrights or other intellectual property rights of another, nor does the Content violate any laws or another’s rights of privacy or publicity. The Content contains no restricted, private, confidential, or otherwise protected data or information that should not be publicly shared. I understand that AgEcon Search will do its best to provide perpetual access to my Content. In order to support these efforts, I grant the Regents of the University of Minnesota ('University'), through AgEcon Search, the following non-exclusive, irrevocable, royalty-free, world-wide rights and licenses: to access, reproduce, distribute and publicly display the Content, in whole or in part, in order to secure, preserve and make it publicly available, and to make derivative works based upon the Content in order to migrate the Content to other media or formats, or to preserve its public access. These terms do not transfer ownership of the copyright(s) in the Content. These terms only grant to the University the limited license outlined above. 000340129 980__ $$a199