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
Point prevalence studies tend to over estimate the occurence of which of the following diseases? 
Select and explain. 
A. Diseases with a high incidence, B. Disease with a long duration, C. Disease with a high moality, D. Diseases with a sho duration
B: Disease with a long duration
Answer: B: Disease with a long duration 
Explanation: .point prevalence of a disease is defined as the number of all current cases old and new of a disease at one point of time.point prevalence can be made specific for age,sex,and other relevant factors or attributes. prevalence studies are mainly employed in the study of those diseases which have a longer duration of action. ref:park&;s textbook,ed 22,pg no 59