The US Centers for Medicare and Medicaid Services, which runs the federal Medicare health insurance plan for elderly people, last month proposed changes to how it pays for clinical trials.

If accepted, the changes would help Medicare compare existing treatments and make scientific and payment decisions that could save money while still providing effective treatment.

Under the current policy, developed in 2000, Medicare pays for certain items and services and for healthcare costs of Medicare beneficiaries who are taking part in clinical trials, but it does not pay for the “investigational” drugs, tests, and devices used in trials even when these drugs, tests, …