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Biases

Here is a list of all Biases in the Catalogue.  Check back regularly as we are adding new ones over time.

 

Previous opinion bias

The results of a previous assessment, test result or diagnosis, if known, may affect the results of subsequent processes on the same patient.

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Racial bias

A distortion arising from systemic, institutional, interpersonal or individual forms of explicit (conscious) or implicit (unconscious) prejudice against individuals or groups based on social constructs of race or ethnicity that influences the planning, methods, results, interpretation, dissemination and application of health research.

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Recall bias

Systematic error due to differences in accuracy or completeness of recall to memory of past events or experiences.

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Referral filter bias

Referral of any group of unwell people from primary to secondary to tertiary care, causing an increase in the concentration of rare cases, more complex cases or people with worse outcomes.

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Reporting biases

A systematic distortion that arises from the selective disclosure or withholding of information by parties involved in the design, conduct, analysis, or dissemination of a study or research findings

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Review biases

Occurs in diagnostic test accuracy studies when the person interpreting the results of the index test has knowledge of the results of the reference standard (diagnostic review bias), or, the person interpreting the results of the reference standard has knowledge of the results of the index test (index review bias). Clinical review bias occurs when relevant clinical and patient information is available to the person interpreting the test or reference result. These are all forms of observer bias.

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Selection bias

occurs when individuals or groups in a study differ systematically from the population of interest leading to a systematic error in an association or outcome.

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Spectrum bias

Occurs when a diagnostic test is studied in a different range of individuals to the intended population for the test

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Spin bias

The intentional or unintentional distorted interpretation of research results, unjustifiably suggesting favourable or unfavourable findings that can result in misleading conclusions

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