The claims are everywhere: on posters and T-shirts, on the Internet and in books, even sometimes headlining the national news. Thomas Jefferson's eccentricities were actually a form of autism. Albert Einstein's genius flourished despite a learning disability. And Winston Churchill overcame a stutter and later suffered from Alzheimer's disease.

The conclusions, made many years after the deaths of these famous men, grab the public's attention, inspire today's patients and bring in money for research and advocacy. There's only one problem: Often, the diagnoses are wrong.

"It's a lie. It's like saying to somebody, `Churchill overcame this; therefore you can.' Maybe you can, but it shouldn't be a lie, or a misrepresentation," said Dr. John Mather, a Washington physician who has debunked several medical myths about Churchill. "It's a matter of forthrightness and accuracy."

The roll call of historic disease sufferers seems endless: Hans Christian Andersen was supposed to be dyslexic. Marie Curie may have had a form of autism. Frederick Chopin could have suffered from cystic fibrosis. Sergei Rachmaninoff may have had Marfan syndrome.

Scholars, physicians and history buffs have always been fascinated by the medical stories behind famous people. The connections are also compelling to the public, who feel they know these figures. At the University of Maryland Medical Center, doctors have been doing post-mortems on historical figures for a decade, and they have grabbed headlines and worldwide attention.

"There's something very powerful about this, particularly for people who don't have any direct experience with the disease," said David Shenk, an author who recently spent time examining similar claims for his book on Alzheimer's, The Forgetting. After extensive work, he concluded Churchill didn't have the condition. Said Shenk: "It's so easy to be reckless about this."

Those who make these retrospective diagnoses, sometimes called "pathographies," say they have researched biographies and other evidence. But historians say old records can be scanty and unreliable. Few if any contemporaries are alive to speak for the dead. And most of the time, the bodies can't be examined.

Yet plenty of people are publicizing their spin on history.

The Stuttering Foundation of America ran a full-page ad in a May issue of the Journal of the American Medical Association, with a photo of Churchill and this headline: "The voice of freedom never faltered, even though it stuttered." The foundation cites five sources, all dated before 1975, making references varying from a "slight stutter" to a "stutter that took him years to overcome." Mather and others say Churchill never had a stutter; they point to tapes of his speeches and a medical evaluation that show Churchill simply had a lisp on his s's and p's.

Likewise, a color poster of six accomplished figures from history, including Andersen, Churchill, Thomas Edison and Einstein, highlights them as people who had learning disabilities and managed to succeed. Created almost 20 years ago by the Hill School in Fort Worth, Texas, the poster has gone into its third printing and is hanging in 41 states and 13 countries. Lucille Helton, the school's former principal, said a committee, looking for famous figures to inspire children, found the information in the local library.

But experts who have closely studied the lives of these men say there is little or no evidence that four of them had a learning disability. Thomas Edison got kicked out of school for not paying attention and later had a hearing problem, but historians say there isn't any proof that he had a learning disability. Similarly, besides speaking later than most children, Einstein never revealed in his schoolwork or voluminous writings problems consistent with a learning disability, experts say.

"Something that can't be proved is taken very blithely as fact," said Marlin Thomas, an expert in learning disabilities at Iona College who published an analysis of the claim about Einstein. Thomas became curious when he saw the diagnosis showcased on T-shirts, Web sites, ads and even brochures from the American Academy of Pediatrics.

Two years ago, Danish researchers published an analysis of Andersen's letters, poems and diaries and concluded a long-standing claim that Andersen was dyslexic was wrong.

It's unclear where the rumor started that Churchill had Alzheimer's. But the connection circulated enough that recently, when Charlton Heston announced he had the degenerative disease, ABC's World News Tonight and Fox television named the former British prime minister as another prominent person who died with the condition.

Celebrity advocates

In a celebrity-driven culture, the strategy is a popular public relations tool. Pharmaceutical companies are increasingly hiring stars with health problems, such as actress Kathleen Turner and skater Dorothy Hamill, to promote medicines. Patient advocacy groups post names of prominent patients on Web sites such as "Famous Texans with Disabilities," "Famous People with Asthma," and a quiz that matches celebrities with their disorders.

"It's just one of the pitiful facts of our society that you have to have a famous person to get the attention," said Abbey Meyers, president of the National Organization for Rare Disorders.

But those who have advanced some of these connections say they have done their homework, closely reading biographies and looking for symptoms and patterns. Jane Fraser, the Stuttering Foundation's president, said Churchill's stutter wasn't always evident because he memorized his speeches.

"I think he [Mather] doesn't have an in-depth understanding of stuttering," Fraser said. "And I think by denying that Churchill stuttered, he's trying to turn it into something to be ashamed of."