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Bias

Bias

Bias refers to any tendency that prevents a question from being considered unprejudiced. In research, bias occurs when one outcome or answer is selected or encouraged over others in sampling or testing. Bias can occur during any research phase, including study design, data collection, analysis, and publication.
In statistics, a sampling bias is created when a sample is collected from a population, and some members of the population are not as likely to be chosen as others (remember, each member...

Ethics in Research

Ethics in Research

Today, scientists agree that good research is ethical in nature and is guided by a basic respect for human dignity and safety. However, this has not always been the case. Modern researchers must demonstrate that the research they perform is ethically sound.

Bias in Epidemiological Studies

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:

Naturalistic Observations

Naturalistic Observations

If you want to understand how behavior occurs, one of the best ways to gain information is to simply observe the behavior in its natural context. However, people might change their behavior in unexpected ways if they know they are being observed. How do researchers obtain accurate information when people tend to hide their natural behavior? As an example, imagine that your professor asks everyone in your class to raise their hand if they always wash their hands after using the restroom. Chances...

Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches

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...

Blind Procedures

Blind Procedures

Ideally, the people who observe and record the children’s behavior are unaware of who was assigned to the experimental or control group, in order to control for experimenter bias. Experimenter bias refers to the possibility that a researcher’s expectations might skew the results of the study. Remember, conducting an experiment requires a lot of planning, and the people involved in the research project have a vested interest in supporting their hypotheses. If the observers knew which child was...

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Bias: considerations for research practice.

Tobias Gerhard¹

¹Center for Education and Research on Mental Health Therapeutics, Institute for Health, Health Care Policy, and Aging Research, and Ernest Mario School of Pharmacy, Rutgers University, New Brunswick, NJ 08901, USA. tgerhard@rci.rutgers.edu

American Journal of Health-System Pharmacy : AJHP : Official Journal of the American Society of Health-System Pharmacists

|November 11, 2008

Summary

Understanding research bias is crucial for accurate health studies. This review covers bias sources, methods to address it, and its impact across study designs.

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Area of Science:

Health research methodology
Biostatistics
Epidemiology

Background:

Bias introduces systematic error into research studies.
Understanding bias is essential for conducting sound research.
Bias can affect study results and their interpretation.

Purpose of the Study:

To review the concept of bias in research.
To identify major sources of bias in health care intervention studies.
To present methods for addressing bias in study design and analysis.

Main Methods:

Literature review of bias in research methodology.
Categorization of bias sources: patient exposure, study inclusion, and assessment/measurement.
Overview of bias mitigation techniques: restriction, matching, multivariate analysis, instrumental variables, and misclassification prevention.

Main Results:

Bias can be introduced through patient treatment exposure, study participant selection, and data assessment.
Methods to address bias include design strategies and analytical adjustments.
Bias mitigation strategies are applicable across various study designs, including randomized controlled trials and observational studies.

Conclusions:

Investigators must proactively avoid bias during study design.
If bias cannot be avoided, it should be adjusted for during analysis.
The impact of any residual bias on study findings must be quantified and discussed.