This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
[{'content': 'Direct standardization is used to compare the mortality rates between two countries. This is done because of the difference in- \nSelect and explain. \nA. Causes of death, B. Numerators, C. Age distributions, D. Denominators', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Adjusted or standardized rates\n\nStandardization (or adjustment) of rates is used to unable the valid comparison of groups that differ regarding an important health determinant (most commonly age).\nFor example, if we want to compare the death rates of two different populations with different age composition, the crude death rate is not right yardstick because rates are only comparable if the populations upon which they are based are comparable.\nTo remove this confounding effect of different age structure, adjustment or standardization is done.\nTwo major approaches to standardization have been used :-\n\n\nDirect standardization\nIndirect standardization', 'role': 'assistant'}]