Breast Cancer Screening

The often confusing issue of screening for breast cancer just got more confusing. First, a major medical group disputed the need for regular mammograms for all women ages 40 to 49, as is currently recommended. Then a widely used computer system that was supposed to make mammograms more accurate was judged to make them less accurate. And guidelines just issued by the American Cancer Society recommend annual M.R.I. scans — in addition to mammograms — for all women at especially high risk of developing breast cancer, starting at age 30.

Nothing in the new material shakes the long-standing recommendation that all women age 50 or older should get regular mammograms. Women in their 40s, however, will need to weigh the pros and cons carefully. Most expert groups believe they should get mammograms every year or two. But clinical guidelines issued by the American College of Physicians take a more discriminating approach.

The guidelines acknowledge that regular mammograms for women in their 40s can reduce the risk of dying from breast cancer by a modest amount: for every 10,000 women screened, six might avoid death from breast cancer. But a very high percentage of the women screened, the college warns, will get false positive results that lead to unnecessary biopsies, increased costs and risk of injury. There is also a tiny risk that radiation from the screening might itself cause cancer. In the end, women deeply worried about breast cancer will want to get screened, while those who judge — with the help of their doctors — that they are at low risk may prefer to wait.

The latest verdicts on two advanced technologies were mixed. One new study found that M.R.I. scans could find tumors that mammograms had missed in a small percentage of women. The downside is that the costly scans are so sensitive they pick up lots of suspicious but harmless growths.

Another new study found that a costly computerized system to help radiologists read mammograms was no better at finding cancer than traditional mammography and led to many more false alarms that required needless biopsies. The computerized systems are used in some 30 percent of all mammography centers, where they are driving up costs for no clear medical benefit. Government and private insurers may need to reconsider whether the systems are worth covering.

The non-aligned movement

The quality of aid matters as much as the quantity
MAIMONIDES, a 12th-century rabbi and philosopher, argued that it is better to give anonymously, like the sages who secretly placed coins under the doors of the poor, than to flaunt your generosity. Better still, he said, to pool your charity—by contributing to a tzedakah box, for example—so that neither the poor nor their benefactor know the other's identity.
The club of 22 governments who dominate foreign aid would not rate very highly by the Torah's reckoning. This week they met in Paris to measure progress on two big commitments made in 2005. In July of that year, those world leaders who gathered for the G8 summit in Gleneagles in Scotland promised to increase aid to $130 billion, and double aid to Africa, by 2010.
But giving freely only gets you past the lowest rank of benefactors in Maimonides' scheme. An earlier pledge, made in Paris four months before, would have impressed him more. Donors promised to be more self-effacing in their charity, to “harmonise” their efforts with other benefactors, and “align” them with the priorities of governments they were trying to help.
Sadly, progress on both pledges is weak.
Such uncertainties should worry a prudent African finance minister. Can he count on seeing some of the extra $25 billion the continent is promised by 2010? Of the G8 leaders who signed that pledge, half have already departed, two are on their way out, and the remaining pair will be gone before 2010. Even if donors meet the target, the aid may arrive in a sudden and unmanageable rush a year or two before the deadline.
Only about 65% of aid actually arrives on schedule, according to the OECD. Finance ministers must cope with shortfalls and windfalls. Zambia was due to receive $930m in 2005, but ended up with just $696m. Vietnam which was expecting about $400m, got roughly $2 billion.
Because the aid they receive is such a capricious, volatile commodity, governments dare not make full use of it. They could hire legions of extra teachers, clinicians and civil servants, but only if they are prepared to fire them when the aid spigot is closed. They could put AIDS-sufferers on anti-retroviral therapies, but only if they are willing to discontinue treatment once the money stops. Not surprisingly, some governments choose to hoard aid rather than spend it. In 2001-03, Ghana received an extra $1.3 billion of aid; $1.2 billion collected in the vaults of its central bank.
Aid is also poorly co-ordinated. A trio of researchers compared donors with a gaggle of crop-growers, spraying water hither and thither, leaving some plants parched, others deluged. After the Indian Ocean tsunami, according to a report in El Pais, an Acehnese girl developed measles symptoms thanks to three identical jabs from different aid agencies.
Where donors and governments do see eye to eye, there may be little need for aid agencies at all. The British government, for example, could simply write a cheque to its Tanzanian counterpart. Some donors do just this, bankrolling governments they trust, and letting them manage the money themselves. About £1.2 billion ($2.4 billion) of British aid will top up government budgets in this way next fiscal year.
Other donors are less enthusiastic. They may want to trumpet their good deeds, or have real or imagined doubts about the recipient's book-keeping and budgeting. Even countries with “moderately strong” exchequers were not always trusted to audit their aid money, the OECD notes. “The very countries that helped us reform our systems, then don't use our systems,” complains Paul Lupunga, a senior Zambian official.
The Paris declaration says that donors must be accountable to beneficiaries. For now, most prefer to please their voters.

Air pressure

America's Supreme Court rules on the environment
THROUGHOUT George Bush’s presidency, the federal government has refused to countenance any regulation of the greenhouse gases that cause global warming. Whenever the subject comes up, officials tend to mumble about uncertainties. But on Monday April 2nd, in its most important environmental decision for many years, the Supreme Court at last settled one of the biggest outstanding questions: whether the government has the authority to curb emissions in the first place.
The court ruled, by the slenderest of margins, that the Clean Air Act—a law from the 1960s designed to combat smog and acid rain-gives the Environmental Protection Agency (EPA) the power to regulate carbon dioxide, the main greenhouse gas. It also said the EPA would need an excuse grounded in the original law if it decided not to use this power. It dismissed the justifications the EPA had provided for inaction—that emissions from American cars were insignificant in the grand scheme of things and that unilateral action by America would undermine efforts to achieve international consensus on global warming—as inadequate. Strictly speaking, the decision applies only to emissions from vehicles, but another, similar case involving coal-fired power plants is pending in a lower court. The EPA says it is now examining the ruling.
It might examine it for some time, of course. Any regulations it comes up with in response might still defer action into the distant future, since the law allows the EPA to delay implementation until appropriate technology can be acquired at a reasonable cost. Even if it proceeds quite swiftly, a new president and Congress with globe-cooling ideas of their own will be in place long before any new rules come into effect.
That suits the environmental lobby just fine. They hope the ruling will spur Congress to address global warming with proper legislation. After all, it makes little sense for such an important issue to be tackled tangentially through a 40-year-old law. At the very least, they can use the ruling to rally the faithful and shame climate-change sceptics in next year’s elections. And if 2009 sees the inauguration of a greener president, he or she will now have the power to dictate stricter fuel efficiency, in the form of lower CO2 emissions, without reference to Congress. If the lawsuit involving power plants goes the same way, the new president will be able to enforce across-the-board cuts in emissions by fiat. As Barbara Boxer, an environmentally-minded senator from California, stated gleefully, “This decision puts the wind at our back.”
That is true of California in particular. In 2002, the state assembly passed a law regulating emissions of CO2 from vehicles, based on a provision of the Clean Air Act that allows California to adopt stricter pollution standards than the federal government (other states can then choose to follow the Californian standards if they wish). Carmakers have challenged the law, in part on the ground that CO2 was not an air pollutant—a notion the Supreme Court has now comprehensively quashed.
California still needs a waiver from the EPA in order to enforce its own emissions standards. The EPA will presumably hesitate to withhold its permission after its setback in court. But it might argue that California does not face the “compelling and extraordinary conditions” the law requires before stricter standards can be imposed. That would prompt another protracted legal battle. On the one hand, global warming is, as its name suggests, a global problem. On the other, a big share of California’s water supply is threatened by decreasing snowfalls in the Sierra Nevada mountains-a change attributed to global warming.
The car industry, at any rate, seems rattled by the ruling. Its trade group quickly declared that the issue of global warming is best handled by at the federal level by Congress. Thanks to the Supreme Court, that now seems more likely.

All washed up

WE WERE right, all along. That is the thrust of the latest report from the Intergovernmental Panel on Climate Change (IPCC), a United Nations body set up to pronounce authoritatively on the science of global warming. In 2001 it predicted that global warming would lead to many ills, including greater numbers of extinctions, growing shortages of water, higher incidence of tropical diseases, and lower yields from agriculture, fishing and forestry in some places. Now the scientists who write the reports say they have much stronger evidence that such calamities are indeed occurring—faster, in many cases, than they originally thought.
The previous IPCC report, in February, examined the evidence that the globe was actually warming. It called the trend “unequivocal”, and expressed “very high confidence” that it was largely man-made. The new report assesses the likely impact of global warming. It was released on April 6th, after a week of negotiations between scientists and governments over the wording. Representatives of China, Russia, Saudi Arabia and America in partiuclar were said to have tried to water down the report, prompting a last-ditch all-night haggle.
The resulting document predicts the same sorts of consequences as its predecessor did in 2001, but with much greater confidence and precision, says Camille Parmesan, a professor at the University of Texas who vetted part of it. By her count, the chapter on current impacts alone rests on a review of over 1,000 academic studies, most of them already published—compared with about 100 last time around.
In a paper published in 2003, Professor Parmesan concluded that half of all species were already altering their behaviour or shifting their range in response to global warming. Others have found that some 26% of coral reefs have already died as a result of warming waters, and that the remainder will probably disappear if average water temperatures rise by another degree—along with the fisheries and tourism they sustain. In a synthesis of such studies, the report concluded that 30% of species face an increased risk of extinction if temperatures rise by 2ºC (3.6ºF).
This sort of finding suggests that the effects of global warming will be “non-linear”, says Paul Epstein, a Harvard University professor who has reviewed the entire report. For one thing, most projections of the impact derive from estimates of changes in average temperature. But many of the ill effects hinge on changes in the minimum temperature, which has been rising twice as fast. This trend is particularly strong near the poles, where the climate is changing fastest. Winters no longer get cold enough in many places to kill off different pests and diseases. So noxious species of ants and bees are marching northwards across America, ticks carrying Lyme disease are proliferating in Scandinavia and tropical highlands around the world are witnessing an invasion of mosquitoes carrying malaria, dengue fever and Japanese encephalitis. “The winter is the most wonderful thing that was ever invented for public health,” Dr Epstein says, “and we're losing it.”
Multiple factors will amplify the effects of global warming on agriculture and forestry. Warmer and drier conditions in many places will reduce yields. Meanwhile, pests such as tree-killing beetles and crop-killing fungi will both increase their range and breed more rapidly. And an increasing incidence of extreme weather, be it floods or droughts, will both damage crops directly and nurture species that prey on them. The poor, especially in tropical climes, will be hardest hit by all this, since they have little means of adapting to such changes.
The report is supposed only to inform policymaking, not to direct it. But the point of the frightening statistics about impending water shortages, epidemics and crop failures, says one of the authors, is to jolt politicians into preparing for the coming afflictions. In other words, the report intends to end the debate between those who think mankind's main effort should be trying to reverse climate change and those who would prefer to concentrate on adapting to its effects. Both strategies, it implies, are urgently needed.