This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Epidemiology, Subject name: Social & Preventive Medicine
[{'content': 'True regarding secular trends- \nSelect and explain. \nA. Changes in disease pattern in terms of months, B. Changes in disease pattern seasonally, C. Changes in disease pattern over a sho period of timer, D. Changes in disease pattern over a long period of time', 'role': 'user'}, {'content': 'Answer: D \nExplanation: .long term or secular trends implies changes in the occurrence of disease over a long period of time.generally several years or decades.a secular trend implies a consistent tendency to change in a paicular direction or a definitive movement in one direction. ref:park&;s textbook,ed 22,pg no 63', 'role': 'assistant'}]