<i>Annals</i> Understanding Clinical Research: Implications of Missing Data Due to Dropout

Abstract

Special Articles18 April 2017Annals Understanding Clinical Research: Implications of Missing Data Due to DropoutJoshua M. Liao, MD and Catharine B. Stack, PhDJoshua M. Liao, MDFrom University of Pennsylvania and American College of Physicians, Philadelphia, Pennsylvania. and Catharine B. Stack, PhDFrom University of Pennsylvania and American College of Physicians, Philadelphia, Pennsylvania.Author, Article, and Disclosure Informationhttps://doi.org/10.7326/M17-0195 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Through a series of "Understanding Clinical Research" articles, Annals aims to help nonstatisticians assess the implications of analytic methods used in research. These articles use illustrations from published studies to identify questions that are critical to understanding particular methods and appropriate interpretation of findings. This installment addresses the issue of missing data due to dropout (for the definition of this and other terms used in the article, see the Glossary)—a common problem that can affect the validity of trial findings. Several analytic methods exist to handle this problem; each has assumptions that require explicit statement and consideration (see the Table).... References1. Bronfort G, Hondras MA, Schulz CA, Evans RL, Long CR, Grimm R. Spinal manipulation and home exercise with advice for subacute and chronic back-related leg pain: a trial with adaptive allocation. Ann Intern Med. 2014;161:381-91. [PMID: 25222385]. doi:10.7326/M14-0006 LinkGoogle Scholar2. National Research Council. Division of Behavioral and Social Sciences and Education. Committee on National Statistics. Panel on Handling Missing Data in Clinical Trials. The Prevention and Treatment of Missing Data in Clinical Trials. Washington, DC: National Academies Pr; 2010. Google Scholar3. Little RJ, D'Agostino R, Cohen ML, Dickersin K, Emerson SS, Farrar JT, et al. The prevention and treatment of missing data in clinical trials. N Engl J Med. 2012;367:1355-60. [PMID: 23034025] doi:10.1056/NEJMsr1203730 CrossrefMedlineGoogle Scholar4. Molenberghs G, Kenward M. Missing Data in Clinical Studies. London: J Wiley; 2007. Google Scholar5. Carpenter JR, Kenward MG. Missing data in randomised controlled trials - a practical guide. Publication RM03/JH17/MK. Birmingham, United Kingdom: National Institute for Health Research; 2008. Google Scholar6. Bell ML, Fairclough DL. Practical and statistical issues in missing data for longitudinal patient-reported outcomes. Stat Methods Med Res. 2014;23:440-59. [PMID: 23427225] doi:10.1177/0962280213476378 CrossrefMedlineGoogle Scholar7. Mallinckrodt C, Roger J, Chuang-Stein C, Molenberghs G, O'Kelly M, Ratitch B, et al. Recent developments in the prevention and treatment of missing data. Ther Innov Regul Sci. 2014;48:68-80. doi:10.1177/2168479013501310 CrossrefMedlineGoogle Scholar8. White IR, Royston P, Wood AM. Multiple imputation using chained equations: issues and guidance for practice. Stat Med. 2011;30:377-99. [PMID: 21225900] doi:10.1002/sim.4067 CrossrefMedlineGoogle Scholar Author, Article, and Disclosure InformationAffiliations: From University of Pennsylvania and American College of Physicians, Philadelphia, Pennsylvania.Acknowledgment: The authors thank the Annals senior clinical and statistical editors for their input and review of earlier drafts of the manuscript.Disclosures: Authors have disclosed no conflicts of interest. Forms can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=M17-0195.Corresponding Author: Joshua M. Liao, MD, Department of Medicine, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104.Current Author Addresses: Dr. Liao: Department of Medicine, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104.Dr. Stack: American College of Physicians, 190 N. Independence Mall West, Philadelphia, PA 19106.Author Contributions: Conception and design: J.M. Liao, C.B. Stack.Drafting of the article: J.M. Liao, C.B. Stack.Critical revision of the article for important intellectual content: J.M. Liao, C.B. Stack.Final approval of the article: J.M. Liao, C.B. Stack.Statistical expertise: C.B. Stack.This article was published at Annals.org on 28 February 2017. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetailsSee AlsoAnnals Understanding Clinical Research: Intention-to-Treat Analysis Joshua M. Liao , Catharine B. Stack , Michael E. Griswold , and A. 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Stack, PhD, Trevor Butterworth, BA, MPhil, MS, and Rebecca Goldin, PhDComment on CONCEPT by Reginster et al : are the authors' interpretations supported by the data analysis?Annals Understanding Clinical Research: Intention-to-Treat AnalysisJoshua M. Liao, MD, Catharine B. Stack, PhD, Michael E. Griswold, PhD, and A. Russell Localio, PhD 18 April 2017Volume 166, Issue 8Page: 596-598KeywordsClinical trialsExerciseExercise therapyForecastingInformation technologyPostural controlRandomized trialsResearch designStatistical dataTechnicians ePublished: 28 February 2017 Issue Published: 18 April 2017 Copyright & PermissionsCopyright © 2017 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...