Senator John McCain is 71 years old, a survivor of an aggressive form of skin cancer. If elected, he would be the oldest man to become president.

These factors are not disqualifying, but they impose on Mr. McCain a larger duty than usual to provide detailed, timely disclosure about his health. So far, he has failed to meet this obligation to voters, even though he is now the presumed Republican nominee.

And it is not just on health issues that there is a lack of transparency in this campaign. Neither Mr. McCain nor Senator Hillary Clinton has been forthcoming enough about financial records.

No presidential candidate should get to the point that he has locked up his party’s nomination without public vetting of his health. And Mr. McCain, in particular, knows that. Early in his first run for president, in 1999, he provided an in-depth look at his medical history: 1,500 pages of medical and psychiatric records collected by a Navy project on the health of former prisoners of war. He has released precious little medical information since his surgery for melanoma in August 2000.