Last month, the White House announced that President Reagan would stop off at the Bethesda Naval Hospital on his way to Camp David "for the first of his normal and routine post-operative exams. . . ." The press release said those exams would include "chest X-rays and blood tests" and that the results would be announced the following week. That was Sept. 18. As yet, there has been no announcement.

Instead, the results of the various tests have been characterized. The first characterization came from the president himself. Emerging from the hospital following his examination, he replied to a shouted question that he had made "a 100 percent complete recovery." Either by coincidence or orchestration, those were precisely the words the White House itself later used in quoting the president's doctors and in describing the results of their tests. It said the results were normal and that the president, at the age of 74, had made complete recovery from both cancer and the operation to remove it.

Let us hope that is the case. But hope is all we have so far, since the test results the White House said would be forthcoming have been withheld. When spokesman Larry Speakes is asked about the results of the president's examination, he says he has nothing to say. In private, other White House aides say Speakes is adhering to Nancy Reagan's policy. She considers detailed reports about her husband's health to be nothing less than an invasion of privacy.

Now may be the time to say why this column is being written. It is not that I know or suspect or have heard that President Reagan's cancer has reoccurred or that he is sick in some other way -- a way that would become obvious if the medical reports were made public. In fact, there is every reason to believe the reports are as described -- clean bills of health. The president -- knock on wood -- is standing tall.

But if that is the case, then there is no reason not to release the reports. Not only would that be consistent with the policy of candor adopted when the president underwent surgery, but it would dispel some of the cynicism resulting from the later attempt to conceal the president's skin cancer. Candor, like virtue, is its own reward.

In July, the country was confident it knew all there was to know. That is not the case now, and no desire for privacy, no matter how sincere, changes any of that. In the first place, the First Family's privacy is invaded all the time -- and often to its advantage. We have seen pictures of a vigorous and ruddy president chopping wood and swimming in the surf. The press covers White House dinners. Nancy Reagan permitted a television crew into the Santa Barbara ranch house and also allowed it to film a staff meeting. When it comes to the First Family, the words "invasion of privacy" are so selectively used that they amount to the familiar version of "national security" -- another excuse for keeping a secret. It's rare that's the real reason for silence.

It's not that there is no such thing as an invasion of privacy. We certainly are not entitled to know things of a strictly personal nature that have noth with the way the country is governed. For instance, it would be interesting to know if Michael Reagan and Nancy Reagan are getting along, but you can hardly insist on some First Amendment right to know it. Juicy is not the same as germane.

The president's health is a different matter. We all have a stake in it. It affects the future of everyone in terms that are so obvious they go without saying. But there is yet another, less tangible, stake the public has too. Ronald Reagan is our president. Even his critics care about the man. In a television age, the term First Family does not connote a kind of American royalty as much as it suggests kinship. When we are talking about the health of a popular president, we are all family.

In due course, the White House's refusal to release detailed results of the tests at Bethesda will only fuel rumors that there is really something to hide. Not only is the president approaching 75, but he will, like anyone, get a cold and look like hell. When that happens, the rumors will start.

The president's health is not a private matter. It's easy to see how Nancy Reagan feels. Ronald Reagan is her husband. Yes. But he's our president.