<i>Annals</i> Understanding Clinical Research: Interpreting Results With Large <i>P</i> Values
Authors: Joshua M. Liao, Catharine B. Stack, Steven Goodman
Journal: Annals of Internal Medicine (2018)

Special Articles2 October 2018Annals Understanding Clinical Research: Interpreting Results With Large P ValuesJoshua M. Liao, MD, MSc, Catharine B. Stack, PhD, and Steven Goodman, MD, MHS, PhDJoshua M. Liao, MD, MScUniversity of Washington, Seattle, Washington (J.M.L.)Search for more papers by this author, Catharine B. Stack, PhDAmerican College of Physicians, Philadelphia, Pennsylvania (C.B.S.)Search for more papers by this author, and Steven Goodman, MD, MHS, PhDStanford University School of Medicine, Stanford, California (S.G.)Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M18-2003 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Reliance on dichotomous or bright-line interpretations of study results (for example, a treatment does or does not work) based solely on P values is widely recognized as a suboptimal research practice, but it remains the dominant method of study interpretation in biomedicine and many other fields. Recognizing this, the American Statistical Association issued a policy statement on statistical significance that attempted to discourage this practice and dispel the notion that any “single index should substitute for scientific reasoning” (1).Treating all results that are not statistically significant as “negative” is a damaging misuse of P values. Doing so confuses 2 ...References1. Wasserstein RL, Lazar NA. The ASA's statement on p-values: context, process, and purpose. Am Stat. 2016;70:129-33. doi:10.1080/00031305.2016.1154108 CrossrefGoogle Scholar2. Altman DG, Bland JM. Absence of evidence is not evidence of absence. BMJ. 1995;311:485. [PMID: 7647644] CrossrefMedlineGoogle Scholar3. Alderson P. Absence of evidence is not evidence of absence [Editorial]. BMJ. 2004;328:476-7. [PMID: 14988165] CrossrefMedlineGoogle Scholar4. Goodman SN. Toward evidence-based medical statistics. 1: The P value fallacy. Ann Intern Med. 1999;130:995-1004. [PMID: 10383371]. doi:10.7326/0003-4819-130-12-199906150-00008 LinkGoogle Scholar5. Goodman SN, Berlin JA. The use of predicted confidence intervals when planning experiments and the misuse of power when interpreting results. Ann Intern Med. 1994;121:200-6. [PMID: 8017747]. doi:10.7326/0003-4819-121-3-199408010-00008 LinkGoogle Scholar6. Callahan CM, Boustani MA, Schmid AA, LaMantia MA, Austrom MG, Miller DK, et al. Targeting functional decline in Alzheimer disease: a randomized trial. Ann Intern Med. 2017;166:164-71. [PMID: 27893087]. doi:10.7326/M16-0830 LinkGoogle Scholar Author, Article, and Disclosure InformationAffiliations: University of Washington, Seattle, Washington (J.M.L.)American College of Physicians, Philadelphia, Pennsylvania (C.B.S.)Stanford University School of Medicine, Stanford, California (S.G.)Disclosures: Authors have disclosed no conflicts of interest. Forms can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=M18-2003.Corresponding Author: Catharine B. Stack, PhD, American College of Physicians, 190 N. Independence Mall West, Philadelphia, PA 19106; e-mail, [email protected]org.Current Author Addresses: Dr. Liao: University of Washington, 1959 NE Pacific Street, BB 1240, Seattle, WA 98195.Dr. Stack: American College of Physicians, 190 N. Independence Mall West, Philadelphia, PA 19106.Dr. Goodman: Stanford University School of Medicine, 259 Campus Drive, T265 Redwood Building/HRP, Stanford, CA 94305.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, S. Goodman.Final approval of the article: J.M. Liao, C.B. Stack, S. Goodman.Statistical expertise: C.B. Stack, S. Goodman.This article was published at Annals.org on 11 September 2018. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics Cited byP-values – a chronic conundrumOptimal dosing of zoledronate to prevent fractures: improving risk‐benefit balanceEffect of Catheter Ablation vs Antiarrhythmic Drug Therapy on Mortality, Stroke, Bleeding, and Cardiac Arrest Among Patients With Atrial FibrillationVitamin D status and bone health: a possible inverse association 2 October 2018Volume 169, Issue 7Page: 485-486KeywordsActivities of daily livingAlzheimer diseaseCaregiversConfidence intervalsConflicts of interestDementiaDisclosureForecastingNursesReasoning ePublished: 11 September 2018 Issue Published: 2 October 2018 Copyright & PermissionsCopyright © 2018 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...