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

Bioequivalence Experimental Study Designs: Repeated Measures, Cross-Over, Carry-Over, and Latin Square Designs01:15

Bioequivalence Experimental Study Designs: Repeated Measures, Cross-Over, Carry-Over, and Latin Square Designs

Bioequivalence experimental study designs play a pivotal role in testing the effectiveness of various treatments. Key among these are the repeated measures, cross-over, carry-over, and Latin square designs. In the repeated measures design, each subject receives all treatments, allowing for temporal comparisons. This type of design is useful in reducing variability but requires careful planning to avoid bias.The cross-over design, an economical method, involves sequential administration of...
Crossover Experiments01:16

Crossover Experiments

Crossover experiments, also called the repeated-measurements design, is a study design in which all experimental units are exposed to all treatments in different periods. Crossover experiments are generally used in psychology, the pharmaceutical industry, agriculture, and medicine.
Crossover designs are performed even with smaller sample sizes since the samples can act as their controls. These are better than simple randomized trials since patients are exposed to all the treatments.
Clinical Trials01:16

Clinical Trials

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...
Clinical Trials: Overview01:11

Clinical Trials: Overview

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...
Bioequivalence Experimental Study Designs: Completely Randomized and Randomized Block Designs01:20

Bioequivalence Experimental Study Designs: Completely Randomized and Randomized Block Designs

Bioequivalence experimental study designs are crucial methodologies used in evaluating and comparing the bioavailability of different drug products. These designs are categorized into various types: completely randomized, randomized block, repeated measures, cross and carry-over, and Latin square designs.Completely randomized designs involve randomly allocating treatments to all subjects participating in the experiment. This allocation is achieved by assigning unique random numbers to subjects...
Randomized Experiments01:13

Randomized Experiments

The randomization process involves assigning study participants randomly to experimental or control groups based on their probability of being equally assigned. Randomization is meant to eliminate selection bias and balance known and unknown confounding factors so that the control group is similar to the treatment group as much as possible. A computer program and a random number generator can be used to assign participants to groups in a way that minimizes bias.
Simple randomization
Simple...

You might also read

Related Articles

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

Sort by
Same author

Not All Randomized Control Trials Are the Same: Response.

The American journal of sports medicine·2026
Same author

Group-Sequential Designs With an Externally-Driven Change of Primary Endpoint.

Statistics in medicine·2025
Same author

In Silico Clinical Trials in Drug Development: A Systematic Review.

Therapeutic innovation & regulatory science·2025
Same author

ACO/ARO/AIO-22 - External beam radiotherapy combined with endorectal high-dose-rate brachytherapy in elderly and frail patients with rectal cancer: A prospective multicentre trial of the German Rectal Cancer Study Group.

Clinical and translational radiation oncology·2025
Same author

Systematic review and meta-analysis of intravenous iron therapy for patients with heart failure and iron deficiency.

Nature medicine·2025
Same author

Intravenous Ferric Carboxymaltose in Heart Failure With Iron Deficiency: The FAIR-HF2 DZHK05 Randomized Clinical Trial.

JAMA·2025

Related Experiment Video

Updated: Jul 1, 2026

A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition
04:53

A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition

Published on: September 20, 2019

A group-sequential design for clinical trials with treatment selection.

Nigel Stallard1, Tim Friede

  • 1Warwick Medical School, The University of Warwick, Coventry, UK. n.stallard@warwick.ac.uk

Statistics in Medicine
|September 16, 2008
PubMed
Summary

This study introduces an advanced group-sequential design for clinical trials, enhancing treatment selection. The new method strongly controls the type I error rate, offering a more reliable approach for comparing experimental treatments against a control.

More Related Videos

The Adjuvant Efficacy of Angong Niuhuang Pill in the Treatment of Viral Encephalitis: A Meta-Analysis of Randomized Controlled Trials
08:36

The Adjuvant Efficacy of Angong Niuhuang Pill in the Treatment of Viral Encephalitis: A Meta-Analysis of Randomized Controlled Trials

Published on: April 19, 2024

Related Experiment Videos

Last Updated: Jul 1, 2026

A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition
04:53

A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition

Published on: September 20, 2019

The Adjuvant Efficacy of Angong Niuhuang Pill in the Treatment of Viral Encephalitis: A Meta-Analysis of Randomized Controlled Trials
08:36

The Adjuvant Efficacy of Angong Niuhuang Pill in the Treatment of Viral Encephalitis: A Meta-Analysis of Randomized Controlled Trials

Published on: April 19, 2024

Area of Science:

  • Biostatistics
  • Clinical Trial Design
  • Pharmaceutical Research

Background:

  • Existing group-sequential designs for treatment selection may not strongly control Type I error rates.
  • Previous extensions allowed multiple treatments but had limitations in error rate control.
  • The need for flexible designs that accommodate factors like safety data is recognized.

Purpose of the Study:

  • To extend group-sequential designs for comparing multiple experimental treatments with a control.
  • To develop a method that strongly controls the familywise Type I error rate.
  • To provide a robust framework for adaptive treatment selection in clinical trials.

Main Methods:

  • Extension of the Stallard and Todd group-sequential design.
  • Incorporation of methods to ensure strong Type I error rate control.
  • Simulation studies to evaluate performance under different selection criteria.

Main Results:

  • The proposed method strongly controls the Type I error rate when the number of treatments is pre-specified.
  • Simulations indicate the design is conservative when treatment selection is data-driven.
  • The approach offers a more reliable statistical framework for adaptive clinical trials.

Conclusions:

  • The extended group-sequential design provides strong Type I error rate control.
  • This offers a statistically sound method for clinical trials involving treatment selection.
  • The design is adaptable and offers improved reliability over previous methods.