Question

1. In the United States, among a representative group of 6,006 white men and 1,126 black men, ages 70-79 years at diagnosis with stage IV prostate cancer, 2,337 white men and 344 black men were alive after 5 years of follow-up. The goal of this analysis is to examine the association between race and survival.

a. What is the exposure and what is the disease? The exposure is race and the disease is stage IV prostate cancer

b. Set up the two by two table for these data with labels for exposures and disease status.

Answer 1

Given data-

Data of 7132 men aged 70-79, in United states, diagnosed with stage IV prostate cancer

Total men (71332) = white men (6006) + black men (1126)

After 5 years, total survivors (2681) = white men (2337) + black men (344)

a. In this case, exposure is: men aged 70-79 (prostate cancer risk increases with age). Disease is prostate cancer.

b. Follwing table shows racewise exposure to prostate cancer and % survival in men aged 70-79

Men aged 70-79	Number of men diagnosed with stage IV prostate cancer	Number of survivors (percent survivors) after 5 years
White men	6006	2337 (38.9%)
Black men	1126	344 (30.55%)