This Article  • Full text  • PDF  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citing articles on Web of Science (1)  • Contact me when this article is cited  Related Content  • Related article  • Similar articles in JAMA  Topic Collections  • HIV/AIDS  • Statistics and Research Methods  • Randomized Controlled Trial  • Infectious Diseases  • Alert me on articles by topic  Social Bookmarking   What's this?

	Since this article does not have an abstract, we have provided the first 150 words of the full text and any section headings.

In Reply: Although the terms "equivalence" and "noninferiority" are not strictly the same, we did use them interchangeably, as is commonly done.¹ This study was designed as a noninferiority study with a prespecified noninferiority margin of 10% chosen as in the "Methods" section.

The 2-sided 95% CI of the difference between 2 trial arms is an appropriate and traditional method for assessing equivalence of 2 treatments.^1-2 The same procedure is often advocated for assessing noninferiority of a new drug (or regimen) compared with a reference drug,¹ even though in noninferiority studies emphasis is on the lower bound of the 95% CI. Indeed, the use of a 2-sided 95% CI (equivalent to a 1-sided 97.5% CI) is advocated by US and European regulatory agencies^3-6 for noninferiority studies. While academic statisticians often use 1-sided 95% CIs to assess noninferiority, we chose the more conservative 2-sided approach, as suggested by these regulatory authorities.

. . . [Full Text of this Article]

Joel E. Gallant, MD, MPH
jgallant@jhmi.edu
Division of Infectious Diseases
Johns Hopkins University School of Medicine
Baltimore, Md

Schlomo Staszewski, MD
Department of Internal Medicine
University Hospital, J. W. Goethe-Universität
Frankfurt, Germany

Anton L. Pozniak, MD
Department of Genitourinary Medicine
Chelsea and Westminster Hospital
London, England

Edwin DeJesus, MD
Infectious Disease Consultants Research Initiative
Altamonte Springs, Fla

Jamal M. A. H. Suleiman, MD
Instituto de Infectologia Emilio Ribas
Sao Paolo, Brazil

Biao Lu, PhD; John J. Toole, MD, PhD; Andrew K. Cheng, MD, PhD
Gilead Sciences
Foster City, Calif

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter     What's this?

RELATED ARTICLE

Tenofovir, Equivalence, and Noninferiority
Jean-Jacques Parienti
JAMA. 2004;292(16):1951.
EXTRACT | FULL TEXT