31.   But the authors said that the trend of recent years would eventually resume, so that a larger proportion of Americans would be uninsured.

32.   But the authors said they found that excess weight carried less risk in the elderly than in younger people.

33.   But the authors said more study was needed to confirm the theory.

34.   But the authors said that the gaps between subprime lending to whites and to minorities were probably too large to reflect credit differences alone.

35.   But the authors said the disparity between Medicare and private insurance did not prove that Medicare was less able to control costs.

36.   But the authors say a companion study of Hispanic students is under way.

37.   But the authors say the trends they saw have accelerated since the surveys were conducted.

38.   But the authors say they have adjusted for that, too, and that without that adjustment the advantage of youth appears to be even greater.

39.   But the authors say this approach ignores the complex chemistry of environmental tobacco smoke.

40.   But the study was not designed to determine the cause of any such biases, the authors said.