Allowing equal interview time to cases and controls can reduce which of the following bias?

Bias: - Type of systematic error. - Subject bias - Recall bias ; Hawthorn bias . - Investigatory bias: Interviewer bias, selection bias, misclassification bias. Allowing equal time for interview can take care of interviewer bias to some extent. Interviewer bias happens in case-control studies where the interviewer knows about the disease status of the person and probes more for exposure amongst cases as compared to controls. - Analyzer bias : Calculation bias - not seen now a days.