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

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

Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches

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, controlled...
Bias in Epidemiological Studies01:29

Bias in Epidemiological Studies

Biases can arise at various stages of research, from study design and data collection to analysis and interpretation. Recognizing and addressing these biases is essential to ensure the validity and reliability of epidemiological findings.Broadly speaking, biases in epidemiology fall into three main categories: selection bias, information bias, and confounding. A more detailed description of possible biases is:
Accuracy and Errors in Hypothesis Testing01:13

Accuracy and Errors in Hypothesis Testing

Hypothesis testing is a fundamental statistical tool that begins with the assumption that the null hypothesis H0 is true. During this process, two types of errors can occur: Type I and Type II. A Type I error refers to the incorrect rejection of a true null hypothesis, while a Type II error involves the failure to reject a false null hypothesis.
In hypothesis testing, the probability of making a Type I error, denoted as α, is commonly set at 0.05. This significance level indicates a 5% chance...
Systematic Error: Methodological and Sampling Errors01:15

Systematic Error: Methodological and Sampling Errors

In the case of systematic errors, the sources can be identified, and the errors can be subsequently minimized by addressing these sources. According to the source, systematic errors can be divided into sampling, instrumental, methodological, and personal errors.
Sampling errors originate from improper sampling methods or the wrong sample population. These errors can be minimized by refining the sampling strategy. Defective instruments or faulty calibrations are the sources of instrumental...
Errors occurring during blood pressure monitoring01:25

Errors occurring during blood pressure monitoring

Blood pressure monitoring is a crucial clinical procedure in diagnosing and managing various cardiovascular conditions. Despite its significance, the accuracy of blood pressure measurements can be compromised by multiple factors, potentially leading to either falsely high or low readings. These inaccuracies are critical as they can significantly impact patient care. So, it is vital to understand these challenges deeply and adopt strategic approaches to minimize errors.
Several factors...

You might also read

Related Articles

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

Sort by
Same author

Do subtle neurological impairments predict treatment resistance to clomipramine in children and adolescents with obsessive-compulsive disorder?

Journal of child and adolescent psychopharmacology·2009
Same author

Impact of generalized social anxiety disorder in managed care.

The American journal of psychiatry·2001
Same author

Mini-SPIN: A brief screening assessment for generalized social anxiety disorder.

Depression and anxiety·2001
Same author

New technologies to improve clinical trials.

Journal of clinical psychopharmacology·2001
Same author

An open-label trial of St. John's Wort (Hypericum perforatum) in obsessive-compulsive disorder.

The Journal of clinical psychiatry·2000
Same author

Randomized trial of a depression management program in high utilizers of medical care.

Archives of family medicine·2000

Related Experiment Video

Updated: Jun 10, 2026

An Open Source Technology Platform to Manufacture Hydrogel-Based 3D Culture Models in an Automated and Standardized Fashion
08:29

An Open Source Technology Platform to Manufacture Hydrogel-Based 3D Culture Models in an Automated and Standardized Fashion

Published on: March 31, 2022

Inaccuracy in clinical trials: effects and methods to control inaccuracy.

K A Kobak1

  • 1Center for Psychological Consultation, 22 North Harwood, Madison, WI 53717, USA. kobak@charter.net

Current Alzheimer Research
|August 14, 2010
PubMed
Summary
This summary is machine-generated.

Clinical trials for Alzheimer's disease face challenges due to inconsistent clinician rating scales. Improving rater training and using independent raters can enhance reliability and reduce trial failures.

More Related Videos

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

Related Experiment Videos

Last Updated: Jun 10, 2026

An Open Source Technology Platform to Manufacture Hydrogel-Based 3D Culture Models in an Automated and Standardized Fashion
08:29

An Open Source Technology Platform to Manufacture Hydrogel-Based 3D Culture Models in an Automated and Standardized Fashion

Published on: March 31, 2022

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

Area of Science:

  • Neuroscience
  • Clinical Trials
  • Gerontology

Background:

  • Clinical trials for mood and anxiety disorders have a high failure rate, a trend now observed in Alzheimer's disease research.
  • Issues with clinician rating scales, including poor inter-rater reliability, interview quality, and rater bias, are contributing factors.
  • Problematic inter-rater reliability in Alzheimer's studies persists even with less subjective measures, often due to a lack of standardized administration and scoring.

Purpose of the Study:

  • To identify key factors contributing to the high failure rate of clinical trials in Alzheimer's disease.
  • To explore the impact of clinician rating scale administration on trial outcomes.
  • To propose potential solutions for improving the reliability and validity of Alzheimer's clinical trials.

Main Methods:

  • Analysis of factors affecting clinician rating scale administration in Alzheimer's studies.
  • Review of existing literature on inter-rater reliability and rater bias in clinical trials.
  • Evaluation of remediation strategies, including training, calibration, and centralized raters.

Main Results:

  • Poor inter-rater reliability, interview quality, and rater bias significantly impact Alzheimer's trial outcomes.
  • Lack of standardization in scale administration and scoring is a primary cause of unreliability.
  • While improved training can help, ongoing calibration is necessary to prevent rater drift.
  • Expectancy bias and baseline score inflation are difficult to remediate and increase placebo response.
  • Centralized, independent raters may help mitigate site-specific issues.

Conclusions:

  • Addressing methodological issues in clinician rating scales is crucial for improving Alzheimer's clinical trial success rates.
  • Implementing standardized procedures, enhanced rater training, and independent central raters are recommended strategies.
  • Further research into novel approaches is warranted, as the cost of methodological improvement should be offset by reduced trial failures.