Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Wedges01:24

Wedges

1.7K
A wedge is a simple machine that serves various purposes, such as adjusting the elevation of structural or mechanical parts, providing stability for heavy objects, and splitting a body into two parts. This versatile tool can amplify an applied force, making it easier to manipulate large or heavy objects.
Consider using a wedge to lift a heavy slab. Here, the wedge functions by converting the applied force into a much larger force directed almost perpendicular to the initial force. This...
1.7K
Trial and Error and Algorithm01:12

Trial and Error and Algorithm

429
A problem-solving strategy is a plan of action used to find a solution. Different strategies have distinct action plans. Trial and error involves trying different solutions until one works. For instance, to fix a broken printer, you might check ink levels, ensure the paper tray isn't jammed, and verify the printer's connection to your laptop. This method can be time-consuming but is commonly used. Thomas Edison, for example, used trial and error to find a suitable filament for the light...
429
Clinical Trials: Overview01:11

Clinical Trials: Overview

5.0K
Clinical development focuses on how the drug will interact with the human body and encompasses four key phases of clinical trials, each serving a specific purpose in assessing the safety and effectiveness of new drugs. These phases overlap and build upon one another. Phase I involves a small group of healthy volunteers (typically 20-80 individuals) or, in cases where significant toxicity is expected, patients with the targeted disease, such as cancer or AIDS. The volunteers are tested for...
5.0K
Clinical Trials01:16

Clinical Trials

10.9K
Clinical trials are prospective experimental studies conducted on humans to determine the safety and efficacy of treatments, drugs, diet methods, and medical devices. Using statistics in clinical trials enables researchers to derive reasonable and accurate conclusions from the collected data, allowing them to make wise decisions in uncertain situations. In medical research, statistical methods are crucial for preventing errors and bias.
There are four phases in a clinical trial. A phase one...
10.9K
Random Error01:04

Random Error

9.8K
Random or indeterminate errors originate from various uncontrollable variables, such as variations in environmental conditions, instrument imperfections, or the inherent variability of the phenomena being measured. Usually, these errors cannot be predicted, estimated, or characterized because their direction and magnitude often vary in magnitude and direction even during consecutive measurements. As a result, they are difficult to eliminate. However, the aggregate effect of these errors can be...
9.8K
Random Variables01:09

Random Variables

17.9K
A random variable is a single numerical value that indicates the outcome of a procedure. The concept of random variables is fundamental to the probability theory and was introduced by a Russian mathematician, Pafnuty Chebyshev, in the mid-nineteenth century.
Uppercase letters such as X or Y denote a random variable. Lowercase letters like x or y denote the value of a random variable. If X is a random variable, then X is written in words, and x is given as a number.
For example, let X = the...
17.9K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Principal stratification with U-statistics under principal ignorability.

Journal of the Royal Statistical Society. Series B, Statistical methodology·2026
Same author

A comparison of methods for designing hybrid type 2 cluster-randomized trials with continuous effectiveness and implementation endpoints.

Statistical methods in medical research·2026
Same author

Advancing palliative care in cardiac arrest and cardiogenic shock: identifying evidence gaps and future research priorities.

Frontiers in cardiovascular medicine·2026
Same author

Addressing Cluster-Level Treatment Effect Heterogeneity in Sample Size Determination for Hierarchical 2 × 2 Factorial Designs.

Biometrical journal. Biometrische Zeitschrift·2026
Same author

Time-Varying Treatment Effect Models in Stepped-Wedge Cluster-Randomized Trials With Multiple Interventions.

Statistics in medicine·2026
Same author

Doubly Robust Estimators of the Restricted Mean Time in Favor Estimands in Individual- and Cluster-Randomized Trials.

Statistics in medicine·2026

Related Experiment Video

Updated: Feb 11, 2026

Author Spotlight: Advancements and Challenges in Surgical Treatments for Postamputation Pain
03:26

Author Spotlight: Advancements and Challenges in Surgical Treatments for Postamputation Pain

Published on: March 8, 2024

3.6K

On Anticipation Effect in Stepped Wedge Cluster Randomized Trials.

Hao Wang1,2, Xinyuan Chen3, Katherine R Courtright4,5

  • 1Department of Biostatistics, Yale University, New Haven, Connecticut, USA.

Statistics in Medicine
|February 10, 2026
PubMed
Summary

Ignoring anticipation effects in stepped wedge cluster randomized trials (SW-CRTs) can bias treatment effect estimates. This study introduces a framework to address anticipation in SW-CRTs, improving accuracy and sample size calculations for these complex trials.

Keywords:
anticipation effectbias formulaexposure timelinear mixed modelsmodel misspecificationsample size calculation

More Related Videos

Author Spotlight: Evaluating the Adjuvant Efficacy and Safety of Angong Niuhuang Pill in Viral Encephalitis Treatment
08:36

Author Spotlight: Evaluating the Adjuvant Efficacy and Safety of Angong Niuhuang Pill in Viral Encephalitis Treatment

Published on: April 19, 2024

1.2K
Author Spotlight: Methodologies and Advancements of Chronic Pain Management Research
08:33

Author Spotlight: Methodologies and Advancements of Chronic Pain Management Research

Published on: January 5, 2024

1.8K

Related Experiment Videos

Last Updated: Feb 11, 2026

Author Spotlight: Advancements and Challenges in Surgical Treatments for Postamputation Pain
03:26

Author Spotlight: Advancements and Challenges in Surgical Treatments for Postamputation Pain

Published on: March 8, 2024

3.6K
Author Spotlight: Evaluating the Adjuvant Efficacy and Safety of Angong Niuhuang Pill in Viral Encephalitis Treatment
08:36

Author Spotlight: Evaluating the Adjuvant Efficacy and Safety of Angong Niuhuang Pill in Viral Encephalitis Treatment

Published on: April 19, 2024

1.2K
Author Spotlight: Methodologies and Advancements of Chronic Pain Management Research
08:33

Author Spotlight: Methodologies and Advancements of Chronic Pain Management Research

Published on: January 5, 2024

1.8K

Area of Science:

  • Biostatistics
  • Clinical Trials Methodology
  • Epidemiology

Background:

  • Stepped wedge cluster randomized trials (SW-CRTs) are increasingly used for evaluating interventions in real-world settings.
  • Standard analysis of SW-CRTs assumes no anticipation of the intervention, which may be violated when awareness of rollout timing influences behavior.
  • Anticipation effects can lead to biased treatment effect estimation in SW-CRTs.

Purpose of the Study:

  • To develop an analytical framework to address and quantify anticipation effects in SW-CRTs.
  • To assess the impact of ignoring anticipation on treatment effect estimators.
  • To provide updated sample size formulas accounting for anticipation and exposure-time heterogeneity.

Main Methods:

  • Derivation of estimator expectations using a collection of linear mixed models.
  • Development of analytical framework to incorporate anticipation effects.
  • Simulation studies and empirical analyses to compare estimators with and without anticipation adjustment.

Main Results:

  • Ignoring anticipation effects results in biased treatment effect estimates in SW-CRTs.
  • The proposed framework provides adjusted estimators that mitigate bias.
  • Updated sample size formulas demonstrate the impact of anticipation on study power.

Conclusions:

  • Accounting for anticipation effects is crucial for accurate treatment effect estimation in SW-CRTs.
  • The developed framework and updated sample size calculations enhance the methodological rigor of SW-CRTs.
  • Practical considerations for implementing anticipation-adjusted analyses are provided.