Biases & Confounders Flashcards
Confirmation Bias
tendency to seek out information that supports something you already believe
Dunning Kruger effect
people perceive a concept or event to be simplistic because their knowledge about is may be simple or lacking
- can lead people to think they are smarter than they are
Cultural Bias
involves those who perceive other cultures as being abnormal, outlying or exotic, simply based on a comparison to their own culture
- created attitudes or stereotypes
In Group Bias
refers to how people are more likely to support or believe someone within their own social group rather than an outsider
Self serving Bias
assumption that good things happen to us when we have done all things right, but bad things happen to us because of circumstances outside our control or thing other people purport
Selection Bias (personal/Cognitive Bias)
refers to the way individuals notice things more when something has happened to make us notice that particular thing more
Confirmation Bias
selective gathering and interpretation of evidence consistent with current beliefs and the neglect of evidence that contradicts them
Anchoring Bias
practice of prioritising information and data that support a clinicians initial impressions, even when first impressions are wrong
Selection Bias (in research)
when individuals or groups in a study differ systematically from the population of interest leading to a systematic error in an association or outcome
- Preventative steps (true randomisation)
Recall Bias
- Systematic error due to differences in accuracy or completeness of recall to memory of past events or experiences
- common problem in studies that use self-reporting, such as pain during the week
Information Bias
- arises from systematic differences in the collection, recall, recording or handling of information used in a study
Observer Bias
process of observing and recording information which includes systematic discrepancies from the truth
Hawthorne Effect
when individuals modify an aspect of their behaviour in response to their awareness of being observed
Lack of Blinding Effect
- blinding is to reduce bias due to knowledge of which intervention or control is being received by study participants
- blinding can be single, double or triple blinded
Volunteer Bias
- Participants volunteering to take part in a study intrinsically have different characteristics from the general population if interest
- sample consists of volunteers
- can include attitudes towards the trial, interventions, and institutions involved
Attrition Bias
unequal loss of participants from study groups in a trial
Publication Bias
likelihood of a study being published is affected by the findings if the study
Correlation
when two factors are related, but one does not necessarily cause the other
Causation
when one factor causes another
Confounders
- influence of an extraneous, third variable , which distorts the association between exposure and outcome variables
- occurs when observed exposure-outcome relationship is in part or wholly due to a third factor
- something than other than the thing being studied, that could be causing the results seen in a study
- commonly occurs in observational studies
Criteria for Confounder
- Independent predictor of the outcome
- Associated with the exposure of interest
- Not an intermediate link in the causal pathway between exposure and outcome
Universal Confounders
Age
Gender
Socioeconomic
