Recall bias

Recall bias (also known as recall error or response bias) is a type of cognitive bias that can occur in epidemiological research. It refers to the systematic error caused by differences in the accuracy or completeness of the recollections retrieved ("recalled") by study participants regarding events or experiences from the past.

Overview

Recall bias can lead to measurement bias and thus affect the validity of epidemiological studies. It is a significant concern in retrospective studies and case-control studies where participants are asked to recall past behaviors, events, or exposures.

Types of Recall Bias

There are several types of recall bias, including:

• Proactive recall bias: This occurs when past memories interfere with the recall of newer events.
• Retroactive recall bias: This occurs when new information interferes with the recall of older memories.
• Motivated recall bias: This occurs when individuals selectively recall memories that align with their current beliefs or feelings.

Impact on Research

Recall bias can significantly impact the results of research studies. It can lead to either an overestimate or underestimate of the association between exposure and disease, depending on whether the bias is differential or non-differential.

Mitigation Strategies

Several strategies can be used to minimize the impact of recall bias in research studies. These include the use of prospective designs, validation studies, blinding, and the use of objective measures of exposure or disease.

See Also

• Cognitive bias
• Epidemiological method
• Bias (statistics)