A town has a population of 500 000. In a 5 year period, 1250 cases of lung cancer were registered by death certification. It was also found in the same town, 500 people were diagnosed with lung cancer from the community hospital. The 1 year survival rate is 0%. What is the SINGLE most likely annual prevalence of lung cancer per million in this population?
A. 200
B. 400
C. 500
D. 700
E. 1250
In this question, we must figure out the total amount of people affected with lung cancer within the 5 year period first: 1250 + 500 = 1750. Therefore, annually there are 1750 / 5 = 350 deaths from lung cancer. This is based on the assumption that the 1 year survival rate is 0% therefore all cases should be accounted for. Since 350 deaths/year is from a population of 500 000, to find out the annual prevalence per million, would be (350 x 1 000 000) / 500 000 = 700 [cross multiply].