1. Consider the following issue:
17.1. A major controversy has occurred about apparent contradictions in biostatistical data as researchers try to convince Congress to allocate more funds for intramural and extramural investigations supported by the NIH. Citing improved survival rates for conditions such as cervical cancer, breast cancer, and leukemia, clinicians claim we are “winning the war” against cancer. Citing increased incidence rates for these (and other cancers), with minimal change in mortality rates, public-health experts claim that the “war” has made little progress, and we should focus on prevention rather than cure.
17.1.1. What explanation would you offer to suggest that the rising incidence of cancer is a statistical consequence of “winning” rather than “losing” the battle?
17.1.2. What explanation would you offer to reconcile the contradictory trends for survival and mortality rates, and to suggest that both sets of results are correct?
The pessimistic explanation is that early detection detects more benign cancers, leading to inflated five-year survival stats. But the question is looking for the optimistic answer.
Brainstorm a reason (or set of reasons) why cancer mortality rates would stay the same even as survival rates go up.
