Review Questions for Crude, Specific, and Adjusted Rates 1 . A. There are 10,000 individuals in City A, which is located in Massachusetts. Eight young individuals and 420 old individuals develop the flu over the course of a year. Use these data to calculate the crude influenza rate per 1,000 individuals per years in City A. B. Now show how to calculate the crude flu rate for City A using weighted average method. The needed information is given in the chart below. Age % of Population in Age Group Influenza Rate per 1,000 Group person-years CITY CITY CITY Massachusetts CITY CITY CITY C A B C A B YOUNG 40 % 50% 80% 60% 2 10 30 OLD 60% 50% 20% 40% 70 110 5 C. What is the crude rate of influenza in City B? D. What is the crude rate of influenza in City C? E. Calculate an age-adjusted influenza rate for each of the cities. Use the age distribution for the State of Massachusetts as the standard