Performing well on some newly introduced HEDIS 2000 measures may be a real challenge for some health plans. The National Committee for Quality Assurance tells Managed Care that four HMOs field-tested the measure controlling high blood pressure, and compiled weak scores of between 32 and 42 percent.... PacifiCare of California has released publicly its second Quality Index, which measures performance of more than 100 physician groups.... A U.S. Senate committee has concluded that the medical field is lagging badly in its Year 2000 computer preparations. More than 90 percent of physicians' offices have yet to address the problem.... The American Association of Health Plans and the National Institutes of Health are trying to reach an agreement that would allow more HMO enrollees to participate in clinical trials. Billing issues arise when members want to join research-related activities.... Most private-practice physicians in British Columbia, Canada, walked off the job for five days last month after a government decision to reduce payments to them. "We're not being paid to work those days," one physician told a Canadian wire service.