Bad Math in the Media

[toonces]

This is a quote from the Guiliani health care advisor explaining why the survival rate for prostate cancer is only 43% in England, compared to 82% in the United States. Guiliani has been using the quote in radio ads over the past month. See if you can figure out where the bad math/logic comes in.

Let me be very clear about why the Giuliani campaign is correct: the percentage of people diagnosed with prostate cancer who die from it is much higher in Britain than in the United States. The Organisation for Economic Co-operation and Development reports on both the incidence of prostate cancer in member nations and the number of resultant deaths. According to OECD data published in 2000, 49 Britons per 100,000 were diagnosed with prostate cancer, and 28 per 100,000 died of it. This means that 57 percent of Britons diagnosed with prostate cancer died of it; and, consequently, that just 43 percent survived.

The article defending this number is here in its enirety.

 

[London Colin]

Lies, damned lies, and statistics ....

http://info.cancerresearchuk.org/cancerstats/types/prostate/incidence

It is estimated that 15–30% of men over 50 have histological evidence of cancer in the prostate rising to 60–70% by the age of 80, but only 1 in 25 men (4%) will die from this disease. In other words, men are more likely to die with prostate cancer than from it.

If testing is much more common and routine in the U.S., while in the U.K. it is more likely to be done in response to someone showing symptoms, then it makes no sense to compare survival rates in the way that has been done. Many of those surviving, having been diagnosed as part of a routine test, will be among the group who would have survived in any case.

 

[toonces]

http://info.cancerresearchuk.org/cancerstats/types/prostate/incidence


If testing is much more common and routine in the U.S., while in the U.K. it is more likely to be done in response to someone showing symptoms, then it makes no sense to compare survival rates in the way that has been done. Many of those surviving, having been diagnosed as part of a routine test, will be among the group who would have survived in any case.

That's essentially true, and is the root cause behind the statistic. But the quote I showed has a fundamental flaw. It says that out of every 100,000 Britons in the year 2000, 49 Britons were diagnosed with Prostate Cancer, and out of every 100,000 Britons in the year 2000, 28 died from Prostate Cancer. However, the people who were diagnosed in the year 2000 are not the same people who died from prostate cancer in the year 2000. They are a completely different group of people. All the statistic says is that the annual death rate is 57% of the diagnosis rate.

 

[London Colin]

I see what you mean

It seems there's a lot of data available, broken down in all sorts of useful and meaningful ways. In summing all that up into a simple headline-grabber, we get conveniently misled.

 

[tgun]

to the point

The question is, "is socialized medicine a good thing or a bad thing"? I'm not sure! Why don't you Brits tell us what you think.


tgun