Biases

Placebo effect

A psychological phenomenon where a patient experiences an improvement in symptoms due to the belief that they are receiving treatment, despite receiving a non-active substance or intervention.

Hawthorne effect

The alteration of people's behavior when they are aware they are being observed, which can skew study results, often resulting in improved performance simply because individuals are being noticed.

Measurement bias

Occurs when data is not accurately recorded in a research study, leading to unreliable results; this can happen due to poor data collection methods or instruments.

Publication bias

The tendency for researchers to handle positive experimental results differently from negative or inconclusive results, leading to a misleading bias; often, studies yielding positive results are more likely to be published.

Observer/experimenter bias

When the researcher allows their expectations to influence the results, leading to distorted data, which can occur unintentionally during data collection or analysis.

Reporting bias

A type of bias where researchers selectively report or omit information based on outcomes or personal beliefs, potentially compromising the integrity of the research findings.

Sampling bias

When the selection of participants is not representative of the entire population, leading to misrepresentation of data; this can undermine the generalizability of study results.

Recall bias

Occurs when participants do not accurately remember previous events, affecting the credibility of research results; this is particularly common in retrospective studies.

Selection bias

Occurs when the selection method produces an outcome not representative of the total population, often due to the way participants are chosen for a study.

Confirmation bias

The tendency to favor information confirming one's pre-existing beliefs while underestimating alternative possibilities, which can cloud judgment and decision-making.

Interviewer bias

A form of bias where the researcher's beliefs can sway the direction of the interview or how responses are interpreted, potentially leading to skewed data.

Social desirability bias

When participants respond in a way that presents them more favorably rather than revealing their true thoughts or feelings; this can compromise the authenticity of survey results.