This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Social & Preventive Medicine
[{'content': 'Randomization is done to reduce ? \nSelect and explain. \nA. Recall bias, B. Selection bias, C. Berksonian bias, D. Repoing bias', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Selection bias Types of bias * Selection bias is a distoion in the estimate of association between risk factor and disease that results from how the subjects are selected for the study. * Information bias is due to systematic measurement error or misclassification of subjects on one or more variables, either risk factor or disease status. * Confounding -results when the risk factor being studied is so mixed up with other possible risk factors that its single effect is very difficult to distinguish. Ref: Park 24th edition', 'role': 'assistant'}]