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

Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches01:23

Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches

157
Biopharmaceutical studies constitute a vital field aiming to enhance drug delivery methods and refine therapeutic approaches, drawing upon diverse interdisciplinary knowledge. In research methodologies, the choice between controlled and non-controlled studies significantly influences the study's reliability and accuracy.
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...
157
Clinical Trials: Overview01:11

Clinical Trials: Overview

3.1K
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...
3.1K
Clinical Trials01:16

Clinical Trials

6.9K
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...
6.9K
Randomized Experiments01:13

Randomized Experiments

7.1K
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...
7.1K

You might also read

Related Articles

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

Sort by
Same author

Securing Commercial Nucleic Acid Synthesis.

Rand health quarterly·2024
Same author

Dependence-Robust Confidence Intervals for Capture-Recapture Surveys.

Journal of survey statistics and methodology·2023
Same author

Geographic and temporal trends in fentanyl-detected deaths in Connecticut, 2009-2019.

Annals of epidemiology·2023
Same author

Randomization for the susceptibility effect of an infectious disease intervention.

Journal of mathematical biology·2022
Same author

Evaluating the Mediating Role of Recall of Intervention Knowledge in the Relationship Between a Peer-Driven Intervention and HIV Risk Behaviors Among People Who Inject Drugs.

AIDS and behavior·2022
Same author

Sociodemographic characteristics and HIV risk behaviors of native-born and displaced Syrian men and transgender women who have sex with men in Lebanon.

AIDS and behavior·2022

Related Experiment Video

Updated: Aug 22, 2025

Preparation of Peripheral Blood Mononuclear Cell Pellets and Plasma from a Single Blood Draw at Clinical Trial Sites for Biomarker Analysis
07:40

Preparation of Peripheral Blood Mononuclear Cell Pellets and Plasma from a Single Blood Draw at Clinical Trial Sites for Biomarker Analysis

Published on: March 20, 2021

17.0K

Randomized controlled trials of biomarker targets.

Margret Erlendsdottir1,2, Forrest W Crawford1,3,4,5

  • 1Department of Biostatistics, Yale School of Public Health, New Haven, CT, USA.

Clinical Trials (London, England)
|November 14, 2022
PubMed
Summary

Randomized controlled trials (RCTs) evaluating biomarker targets can yield conflicting results. Causal reasoning reveals threats to validity, including blinding issues and adaptive treatment strategies, necessitating critical assessment of meta-analyses and trial designs.

Keywords:
Intention-to-treatcausal inferencehypertensionmeta-analysisrandomized controlled trial

More Related Videos

Dried Blood Spot Collection of Health Biomarkers to Maximize Participation in Population Studies
07:20

Dried Blood Spot Collection of Health Biomarkers to Maximize Participation in Population Studies

Published on: January 28, 2014

36.6K
Selecting Multiple Biomarker Subsets with Similarly Effective Binary Classification Performances
07:35

Selecting Multiple Biomarker Subsets with Similarly Effective Binary Classification Performances

Published on: October 11, 2018

7.6K

Related Experiment Videos

Last Updated: Aug 22, 2025

Preparation of Peripheral Blood Mononuclear Cell Pellets and Plasma from a Single Blood Draw at Clinical Trial Sites for Biomarker Analysis
07:40

Preparation of Peripheral Blood Mononuclear Cell Pellets and Plasma from a Single Blood Draw at Clinical Trial Sites for Biomarker Analysis

Published on: March 20, 2021

17.0K
Dried Blood Spot Collection of Health Biomarkers to Maximize Participation in Population Studies
07:20

Dried Blood Spot Collection of Health Biomarkers to Maximize Participation in Population Studies

Published on: January 28, 2014

36.6K
Selecting Multiple Biomarker Subsets with Similarly Effective Binary Classification Performances
07:35

Selecting Multiple Biomarker Subsets with Similarly Effective Binary Classification Performances

Published on: October 11, 2018

7.6K

Area of Science:

  • Clinical research methodology
  • Biostatistics
  • Causal inference

Background:

  • Randomized controlled trials (RCTs) are standard for estimating treatment effects.
  • Biomarker targets are increasingly used in RCTs for conditions like hypertension.
  • Conflicting recommendations and inconclusive meta-analyses have emerged from trials of biomarker targets.

Purpose of the Study:

  • To explain, using causal reasoning, why RCTs of biomarker targets can produce misleading conclusions.
  • To identify key threats to the validity of trials that use biomarker targets.

Main Methods:

  • Causal reasoning applied to analyze potential biases in biomarker target trials.
  • Examination of four key threats: intention-to-treat with lack of blinding, incomparability across trials, time-varying adaptive treatment strategies, and Goodhart's law.
  • Illustration using 15 RCTs of blood pressure targets for hypertension management.

Main Results:

  • Intention-to-treat analysis can be misleading without blinding.
  • Significant variation exists in patient populations, therapies, and treatment strategies across trials.
  • Lack of accounting for time-varying treatment strategies and potential off-target effects complicates interpretation.

Conclusions:

  • Meta-analyses of target trials require critical assessment for therapy variations and off-target effects.
  • Future RCTs should compare treatment algorithms incorporating biomarkers, not just targets.
  • Causal inference methods adjusting for time-varying confounding are recommended for observational studies.