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Clinical Trials

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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.
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Related Experiment Video

Updated: Jun 26, 2026

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

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

Published on: September 20, 2019

Considerations in adapting clinical trial design.

H M James Hung¹

¹Division of Biometrics I, Office of Biostatistics and Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Maryland, USA. hsienming.hung@fda.hhs.gov

Journal of the Formosan Medical Association = Taiwan Yi Zhi

|January 9, 2009

Summary

Adapting clinical trial designs during a study is gaining traction due to complex hypotheses and insufficient pre-trial data. However, these adaptations require careful management to avoid bias and ensure interpretable results.

Related Experiment Videos

Last Updated: Jun 26, 2026

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

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

Published on: September 20, 2019

Area of Science:

Clinical trial methodology
Pharmaceutical research
Biostatistics

Background:

Increasing complexity of clinical trial hypotheses and decision trees.
Insufficient pre-trial data for robust pivotal trial design.
Limitations of conventional fixed trial designs in accommodating complex statistical needs.

Purpose of the Study:

To explore the concept and implications of adapting clinical trial designs.
To address the challenges posed by complex statistical decision trees.
To investigate the balance between design flexibility and methodological rigor.

Main Methods:

Review of current practices in clinical trial design adaptation.
Analysis of the statistical challenges associated with adaptive designs.
Examination of regulatory considerations for protocol amendments.

Main Results:

Growing interest in adaptive trial designs within the pharmaceutical industry.
Protocol amendments are a common regulatory mechanism for design adjustments.
Potential for bias and reduced interpretability due to design modifications.

Conclusions:

Adaptive clinical trial designs offer potential benefits for complex studies.
Careful consideration of bias and interpretability is crucial for adaptive designs.
Further research is needed to optimize adaptive trial methodologies and regulatory oversight.