In: Statistics and Probability
In 2019, the University of Alabama (UA) homecoming event took
place in Tuscaloosa from July 21 until July 24, 2019. People at the
event included UA Alumni, their families, and friends who did not
attend UA. Between August 3 and August 15, some of those who had
been present at the event became ill with a type of pneumonia. No
one attending the event had the disease before July 21, 2019. The
number of UA alumni and non-Alumni who acquired the illness between
August 3 and August 15, 2019, is shown in the table
below.
Had pneumonia
Yes No
Non-UA Alumni 50 750
UA Alumni 300 900
1) Compute the cumulative incidence of pneumonia among UA Alumni
Interpret the result
2) Compute the cumulative incidence of pneumonia among Non- Alumni
Interpret the result
3) Calculate the cumulative incidence ratio of pneumonia among UA Alumni compared to Non- Alumni
Interpret the result
4) Calculate the cumulative incidence difference of pneumonia among UA Alumni compared to Non- Alumni. (2pts)
Interpret the result
(1)
The cumulative incidence of pneumonia among UA Alumni =
= = 0.25
Interpretation: 25% of pneumonia in the period of Aug 3 to Aug 15 among UA alumni.
(2)
The cumulative incidence of pneumonia among Non - Alumni =
= = 0.0625
Interpretation: 6.25% of pneumonia in the period of Aug 3 to Aug 15 among Non-alumni.
(3)
Cumulative incidence ratio of pneumonia among UA Alumni compared to Non- Alumni =
=
= 4
Interpretation: Here the person who belongs to UA alumni has 4 times the risk of affecting pneumonia as compared to the person who belongs to Non alumni.
(4)
Cumulative incidence difference of pneumonia among UA Alumni compared to Non- Alumni
= CI among UA alumini - CI among Non Alumni = 0.25 - 0.0625 = 0.1875
Interpretation: There were 1875 cases with pneumonia out of 10000 among UA Alumni as compared to Non-Alumni