When president is ill or injured, who needs to know?

(CNN) -- March 30, 1981. Arguably the most powerful man in the world is shot.

As measures were taken to save President Reagan's life, the press was trying to bring the story to the American people. But information was scarce; the media both at the scene and at the hospital had no idea just how serious it was.

"We did not know, the general public or the press, how near death he was when he collapsed in the ER," recalled Sam Donaldson, a former ABC White House correspondent. "The first briefing did not give us any of those details; the first briefing was a fairly upbeat briefing."

Former White House reporter Helen Thomas has covered every president from John Kennedy to George W. Bush for United Press International. She says the atmosphere was tense and the answers few.

"We were asking many questions, which the White House refused to answer. There was a great sense of frustration in terms of what was really going on," Thomas said.

Today, HIPAA, the Health Insurance Portability and Accountability Act, protects the privacy rights of ordinary Americans, but what about when the patient is the president?

Over the years, covering a health crisis has been a delicate dance for the White House Press Corps. History shows that administrations have for years covered up presidential illness. Take a quiz on presidential health facts »

Woodrow Wilson had a series of small strokes before he was sworn in to office in 1913. It wasn't known whether he would survive his first term, and his doctors never talked about it.

Presidential historian Robert Dallek said Wilson suffered a debilitating stroke in 1919. He and his doctor discussed the possibility that Wilson would resign, but his wife talked him out of it. According to Dallek, she largely ran the presidency in 1920.

Elected to the first of four terms in 1932, Franklin Delano Roosevelt was paralyzed from the waist down with polio. In private, he used a wheelchair, but in public, it was a different story. He was able to downplay his disability -- it's said with the media's help -- and was almost always photographed without his chair. Gravely ill, Roosevelt died less than six months into his fourth term, even though his personal physician claimed that he was in excellent health.

In 1955, Dwight Eisenhower suffered a massive heart attack while vacationing in Denver, Colorado. Facing a run for re-election, he and his staff tried to minimize the political impact.

"We usually received evasive answers," Thomas said. "James Haggerty, the press secretary and a former reporter, insisted on relaying the un-garbled truth about Ike's illness. Even then, reporters were given confusing details: some calling it a heart attack, others a stroke."

Eisenhower announced that he would seek another term when he was cleared by his doctors five months later.

Even presidents who were in good physical health have had medical emergencies while in office. On September 15, 1979, President Carter collapsed while running a 10k race near Camp David, Maryland. After a few tense minutes, he was diagnosed with heatstroke.

"By the time we'd heard about the incident ... they'd ruled out heart attack; they'd ruled out something terrible," Donaldson remembered. "He'd simply collapsed from a combination of exhaustion; he'd lost weight; he'd run himself ragged, if you will, in those months of his presidency."

Dallek says the public is entitled to a full accounting of the medical condition of the commander in chief but often doesn't get it. Kennedy had a number of illnesses kept from the public, as was Richard Nixon's drinking, according to Dallek.

"The people around them want to shield them from the public knowledge that this is an individual who is not going to be able to function all that effectively," Dallek said. "They think they're doing it to serve the national well-being, because the public doesn't want to be so alarmed that a president is immobilized and cannot face a possible foreign or domestic crisis that might emerge."

The balance between personal privacy and the public's right to know has shifted some over the years. More recent administrations have been a little more accommodating, a little more open about the health of U.S. presidents. In the search for answers, verbal sparring between the press and White House spokesmen is common. Donaldson said reporters often have to dig deep.

"White House doctors were forthcoming to the extent, I think, that they didn't lie about the information," Donaldson said. "But there's a difference between lying about something and telling it all, expanding on it and giving us the detail ... and I think in that sense, they weren't that forthcoming."

Former CNN White House correspondent Charles Bierbauer remembers covering George H.W. Bush when the president fell ill at a state dinner in Japan on January 8, 1992. He says he watched in frustration as it all unfolded on a video monitor in the Banquet Hall.

"We couldn't hear what was going on; we could only see pictures. Which only adds to the consternation of what's happening and how do we find out," Bierbauer said. "We tried to get in touch with the White House press office. ... I or the producer would get on the phone and say, 'We need to talk to Marlon [Fitzwater],' and they would say, 'Marlon can't talk right now.' "

But some in the working press feel that we're seeing a new era and the lines of communication are getting better.

In 2002, when President George W. Bush choked on a pretzel and passed out while watching a Miami Dolphins football game in the White House residence, then-White House press secretary Ari Fleischer alerted the press immediately.

"If the president has a little skin tag removed, does the country need to know? Now, I can make a case for privacy there," Fleischer said.

"President passes out, country needs to know. So there is still a zone of medical privacy that presidents and candidates should be entitled, to but I think it's a small and it's a narrow zone. Anything that could affect a performance in office, I think the public has a right to know."

Of course, when the president is sporting a bruise on his face that's nearly the size of a quarter, there's really no way to keep that under wraps or hidden from the White House Press Corps.

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