But you’d never know that reading AEI’s highly dubious contribution to the literature in this week’s Health Affairs (lay Reuters article here). Consistent with their free-market solves everything and can do no wrong (cover ears and yell “nananananananana”) attitude towards the broken US healthcare system, they have managed to contaminate the literature with a paper that suggests our higher expenditures on cancer are generating significant returns in patient survival. Except that it doesn’t show this, and to her great credit, Reuter’s Sharon Begley nails it:
Cancer patients in the United States who were diagnosed from 1995 to 1999 lived an average 11.1 years after that, compared with 9.3 years for those in 10 countries in Europe, researchers led by health economist Tomas Philipson of the University of Chicago reported in an analysis published Monday in the journal Health Affairs.
Those extra years came at a price. By 1999 (the last year the researchers analyzed), the United States was spending an average of $70,000 per cancer case (up 49 percent since 1983), compared with $44,000 in Europe (up 16 percent). Using standard figures for an extra year of life, the researchers concluded that the value of the U.S. survival gains outweighed the cost by an average $61,000 per case. The greater spending on cancer care in the United States, they conclude, is therefore “worth it.”
Experts shown an advance copy of the paper by Reuters argued that the tricky statistics of cancer outcomes tripped up the authors.
“This study is pure folly,” said biostatistician Dr. Don Berry of MD Anderson Cancer Center in Houston. “It’s completely misguided and it’s dangerous. Not only are the authors’ analyses flawed but their conclusions are also wrong.”
I am amazed, this is real science reporting here, because rather than just doing a press-release rehashing of the AEI-authors’ dubious assertions, she found some real cancer experts and shredded it.
The mistake they made, or possibly ignored, is lead-time bias. By using survival from diagnosis, rather than the patient’s actual mortality, they create the appearance of improved outcomes. But the reality is, earlier diagnosis is creating a false survival signal. The US isn’t actually extending lives in comparison to treatment in other countries, the overall mortality rates are the same.
Further the paper only showed the benefit in prostate cancer and breast cancer, and, if anything, worse survival for colon and uterine cancer given the amount of expenditure. The reason is pretty straightforward, and consistent with the lead-time bias issue. In the US, we probably over-screen for breast and prostate cancer, which means more people live with these diagnoses than do in other countries. It’s been a topic of debate among medical professions and discussed extensively by other medical bloggers like Orac because it’s quite possible, especially for breast and prostate cancers, that screening protocols are too inclusive. The result is there are more patients in the US that are given a cancer diagnosis, but they have disease that may never progress to being a life-threatening illness. Excessive screening may even result in unnecessary procedures and treatments when it comes to these two diseases, and we are still trying to work out what protocols will include the most patients with serious disease, while excluding as many false-positive patients as possible. This is acknowledged by Begley’s expert reviewers:
Even more problematic, said Berry, is a problem cancer experts have only recently recognized: overdiagnosis. Because cancer screening is much more widespread in the United States than in Europe, especially for breast and prostate cancer, “we find many more cancers than are found in Europe,” he said. “These are cancers that tend to be slowly growing and many would never kill anyone.”
Screening therefore turns thousands of healthy people into cancer patients, even though their tumor would never threaten their health or life. Counting these cases, of which there are more in the United States than Europe, artificially inflates survival time, experts said.
“As long as your calculation is based on survival gains, it is fundamentally misleading,” said Dr. H. Gilbert Welch, a healthcare expert at the Dartmouth Institute for Health Policy & Clinical Practice.
In the new analysis, the survival gains in the United States compared with Europe were greatest for prostate cancer, at more than triple the gains for breast cancer, the cancer with the second-greatest U.S. survival edge. “These are the two cancers where screening has raised the most serious issues about lead-time bias and overdiagnosis,” said Welch.
For melanoma and colorectal and uterine cancer, survival gains over the period analyzed were greater in Europe than the United States.
If anything the opposite is true based on the correct analysis which is based on mortality statistics, not survival.
Other calculations cast doubt on the superiority of U.S. cancer care. For instance, breast cancer mortality fell 36 percent in the United Kingdom from 1990 to 2006, calculates MD Anderson’s Berry, and fell 30 percent among whites in the United States. (The U.S. figure would be even lower, he said, if it included African-Americans, who generally have less access to health care.)
Cancer mortality in the United States is higher than in 11 countries reporting to the Organization for Economic Co-operation and Development, and lower than the rate in 14. Mortality is lower in Switzerland, Sweden, Japan and Finland, among others, but higher in Hungary, Slovenia, France and Britain, in the latest years for which OECD has data.
The reduction in cancer mortality in the United States since 2000 also puts it toward the middle of OECD countries. It is less than in Israel, Japan, Switzerland and some others, for instance, but better than in Britain, Estonia and Poland.
To sum up, the authors successfully identified lead-time bias in two cancers which the US is known to screen more for than other nations with universal healthcare systems that have health expenditures of roughly 50% less than ours, per capita. They then falsely attributed this lead time bias to our excessive health expenditures, then generalized this biased finding to suggest our excessive expenditures overall provide benefit to our population. This is despite a large body of literature, using appropriate measures of health outcomes, that suggest many other countries do better than us in cancer and medically-preventible disease mortality in general.
It is amazing that this paper passed peer-review, and that such a substandard analysis by authors with clear ideological biases was not detected and rejected. And one could have predicted this considering the author’s affiliation with AEI and Manhattan Institutes, think tanks which routinely engage in denial of science like global warming. This is a comparable mistake to accepting a paper from the Discovery Institute, or Peter Duesberg without approaching it with a hefty dose of skepticism. Anti-science ideologues tend to write shoddy, unscientific papers, and some basic peer review should have prevented this analysis from contaminating the literature.
Shame on Health Affairs for publishing this garbage, but let’s a salute Reuter’s for doing an excellent job in appropriate post hoc review of this flawed paper.
Leave a Reply