JAMAevidence JAMA Guide to Statistics and Methods

Natalie Exner Dean, PhD, associate professor of biostatistics and bioinformatics at Emory, studies infectious disease and vaccine effectiveness. She explains enrolling symptomatic people, using test-positives versus test-negatives to estimate effectiveness. She covers calculating effectiveness from odds ratios, key assumptions about disease specificity, bias reduction via healthcare-seeking restrictions, and limits from test performance and misclassification.

Steve A. Webb, intensive care physician and professor specializing in adaptive and platform trial design. He explains what platform trials are and how they differ from traditional single-question studies. He describes adding and dropping interventions adaptively. He highlights operational and statistical efficiencies, handling heterogeneity, and when platforms may not be appropriate.

Kendra D. Sims, PhD, postdoctoral associate in Epidemiology, Boston University, discusses Tipping Point Analysis: Assessing the Potential Impact of Missing Data with JAMA Statistical Editor Roger J. Lewis, MD, PhD. Related Content: Tipping Point Analysis

Edward C. Norton, PhD, University of Michigan Health Management and Policy, discusses Instrumental Variables and Heterogeneous Treatment Effects with JAMA Statistical Editor Roger J. Lewis, MD, PhD. Related Content: Instrumental Variables and Heterogeneous Treatment Effects

Jody D. Ciolino, PhD, Northwestern University, Feinberg School of Medicine discusses Factorial Clinical Trial Designs with JAMA Statistical Editor Roger J. Lewis, MD, PhD Related Content: Factorial Clinical Trial Designs Reporting of Factorial Randomized Trials

Maria Mori Brooks, PhD, University of Pittsburgh School of Public Health, discusses "Assessing Unexpected Circumstances That Lead to Modifications in Clinical Trial Design, Conduct, or Analysis" in the JAMA Guide to Statistics and Methods series, with JAMA Statistical Editor Roger J. Lewis, MD, PhD. Related Content: Assessing Unexpected Circumstances That Lead to Modifications in Clinical Trial Design, Conduct, or Analysis

In this engaging discussion, Lars W. Andersen, a professor at Aarhus University Hospital renowned for his work in acute care, delves into the intricate world of collider bias with statistical editor Roger J. Lewis. They clarify its critical importance in ensuring accurate treatment effect estimates in research. Lars illustrates collider bias using examples from diet and cognitive assessments and discusses its implications in COVID-19 medication studies. He emphasizes the need for rigorous study designs and thoughtful population selection to mitigate this pervasive bias.

John M. Lachin, ScD, Biostatistics Center, George Washington University, discusses Nonparametric Statistical Analysis with JAMA Statistical Editor Roger J. Lewis, MD, PhD. Related Content: Nonparametric Statistical Analysis

Andrew D. Althouse, PhD, University of Pittsburgh School of Medicine discusses The Use of Historical Controls in Clinical Trials with JAMA Statistical Editor Roger J. Lewis, MD, PhD. Related Content: The Use of Historical Controls in Clinical Trials

Barbara Wendelberger, PhD, Berry Consultants, discusses Futility in Clinical Trials with JAMA Statistical Editor Roger J. Lewis, MD, PhD. Related Content: Futility in Clinical Trials