MCQ – 11720

In a population of 5000 people, 500 are already myopic on January 1, 2011, number of new myopic cases till December 31, 2011, is 9. Calculate incidence:

Correct Answer » B Explanation

Correct Answer:
– Incidence = (New cases / Total population at risk) × 100.
– Total population at risk = 5,000 (excluding existing myopic cases).
– New cases = 9, so incidence = (9 / 5,000) × 100 = 0.18%.
– Rounding to one decimal place gives 0.2%.