Introduction to Epidemiology 6th Edition by Ray M Merrill

Exercise 17

There were recently 120 people diagnosed in a certain region with disease A. A total of 440 persons lived in the households where these cases resided. If 50 of these diagnosed patients were primary cases, what is the secondary attack rate?

Step 1 of 2

Secondary attack rate (SAR) can be defined as those new cases that are happened due to the primary cases that are already happened previously. Mathematically, this can be calculated by a formula which is described below: