If you think it’s good news that the death rates by stroke, heart disease, cancer, and just plain accidents have declined last year (diabetes deaths have remained steady), then you’re not trying hard enough to find the dark lining to this silver cloud.
But, thank goodness, death rates from COPD have “skyrocketed“, so we don’t need to stop worrying! The New York Times even supplied a graph (below) as evidence of this calamity.
There are two things wrong with this bleak outlook. The first is an error in logic, the second is one of bad graphics.
Can you see what’s wrong with the statistical graph? Looks like a dramatic increase in COPD deaths, right? Well, maybe. But hasn’t the population, for men and women, also increased—skyrocketed—since 1980? I have only been able to discover (from this site) the COPD deaths per 100,000 up until 2004 (not 2005 like the Times picture), but here is that picture:
They certainly increased a bit for women, stayed steady for men, and even leveled off around 2000 for women. No skyrockets here. This leads to a simple graphics rule: always normalize by the base population!
To investigate the logical error, first read this, which is advice doctors are supposed to give patients on hearing the allegedly cheering news that death rates have fallen (advice is from this site):
Explain to patients that while age-adjusted death rates are declining, heart disease, stroke, cancer, accidents, COPD and diabetes remain the leading causes of death
Ready? First, that list of things that can kill you together caused nearly all deaths. Now, it is an observational fact that these diseases, heart disease, stroke, accidents, and cancer are killing people at a slower rate, and that diabetes kills at the same rate. It is also true that people are dying each year. And something must kill these people. Therefore, since COPD is the only major killer left in the list, death rates due to it must increase, even if the behaviors and external causes that lead to COPD remain unchanged.
The corollary to this is that you have to die of something, and that some disease will have to be the leading cause of death. No matter how much money you spend, or how many laws that you pass, or how much you exercise and diet, some malady will always be Number One in the Grim Repear’s play book.