My grandfather always said, "You're your own best doctor." But he didn't live to see the Information Age and couldn't have foreseen the anarchy that would ensue when his nutty granddaughter could Google "colon cancer symptoms" every time she got constipated. (Not that I ever get constipated, or even have bowels.)
The Internet has become a mind-blowing informational resource that's enabled patient self-advocacy on an unprecedented level. And isn't it all about self-advocacy these days, when our doctors have only milliseconds to spend with us? We've all seen those news stories about some plucky patient who did her homework and found out that rash was really caused by African sleeping sickness.
However, the stress of reading bullet points about jaundice and abdominal bloating has probably taken years off my life. At what point should I just close my browser and pop a laxative?
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Search and Destroy
If you enter "headache" into a search engine, it's likely that you'll get as many results for brain tumors as you will for caffeine withdrawal, says Eric Horvitz, M.D., Ph.D., a Microsoft researcher who studies how consumers use the Web for health information. Caffeine headaches are common; your chance of having a brain tumor is about 1 in 10,000.
"But brain tumors are a scary, interesting, salient topic, and so there's much more text on the Web about them," Horvitz says. Most search engines are expert at information retrieval, but they don't necessarily consider uncertainties."
As a result, Web searches often link garden-variety symptoms to rare conditions, leaving you there shivering at your laptop and assuming that your dry cough means death is nigh.
Statisticians have a term for that: "base-rate neglect, which is what happens when you make assumptions drawn from the evidence in front of you rather than a studied consideration of actual probabilities.
Neglect? I've always thought it was the opposite of neglect, striving to label my every ache and itch. But I feel sheepish when I consider the last time I entered my symptoms in a search engine: ''Fatigue'' plus "joint pain" yielded lupus, arthritis, chronic fatigue syndrome, and fibromyalgia -- and that was only the first page of results.
Fret though I did, I never went to the doctor, and the pain went away when I stopped freelancing and went back to work in an office. (Funny, my search hadn't yielded anything about isolation or existential despair.)
Even med students often famously experience medical schoolitis, also called "second-year syndrome" because it tends to set in during the second year of med school, when students have read about all kinds of horrific conditions but haven't yet started seeing patients and tuning up actual probabilities. Horvitz says, ''I wonder whether the Web makes second-year med students of all of us."
When it comes to using the Internet to pinpoint the real likelihood of dreaded conditions, it's much harder to find out what you probably don't have than what you infinitesimally might.
For research purposes, Horvitz pretended to be a 33-year-old with chest pains and did a Web search for his symptoms: It took an hour for him to unearth the actual statistical improbability of heart attack for somebody that age with no genetic predisposition.
"It would take a Sherlock Holmes to find out I likely had nothing to be concerned about," he says.
A diagnosis is a complicated thing, says Lisa Sanders, M.D., New York Times columnist and consultant behind all those magnificent, baroque diagnoses on "House." (She never got over her second-year syndrome: "Oh, I have brain cancer about once a year. Wait, that's not normal?")
She says, "The body has an extremely limited repertoire of ways to make you feel bad. You can describe pain, location, duration -- but this vocabulary has to cover the millions of ways the body can go wrong. Actually, you're in the worst position when you only know what your symptoms are."
The first cut of a diagnosis, Sanders adds, isn't even about your complaints; she initially considers a patient's gender, age, medical history, and parents' medical history.
''Dr. William Osler, the father of American medicine, said it's more important to know about the patient than to know about the disease,'' Sanders says. ''If you hear the patient's story -- the who, what, when, where, and why -- 80 percent of the time it will tell you what she has before she even tells you."
And yet it's hard to remember the empirical niceties when the body sends you one of its dumb, blunt messages: I'm suffering. Even Alice Domar, Ph.D., executive director of the Domar Center for Mind/Body Health, says that a few years ago when her right lower leg went numb, she made a panicked Internet house call and assumed she had multiple sclerosis, not even thinking about the fact that two days before, she'd carried her 70-pound daughter into the ER after a roller-blading accident.
"I saw the doctor on a holiday because I was so worried," she says. "When you come up against leg weakness as a female in your 40s, that's the malady that keeps popping up. You read the symptoms: Tired? Well, yeah, I'm tired. Blurred vision? I can't read as clearly as I used to. I forgot about common sense.''
People do get sick, and sometimes serious conditions do start with simple symptoms. I could not resist pressing Sanders for the three that should make us pay special attention (Chest pain? Shortness of breath? Loose teeth?), but she sensibly refused to humor me.
"It's too hard to make generalized statements," she says. "If you've had chest pain for five years, I'm not worried. If you have severe substernal chest pains that started five minutes ago, then I am extremely interested in that. Context is everything.''
If we're really our own best doctors, the sound approach may be to do what the best doctors do and consider the patient first. Domar has her patients keep a symptom diary: Do their symptoms appear only on workdays? When they eat a certain food? When they've slept badly? When their mother-in-law is visiting?
"If a symptom appears out of the blue, I think you have to look back and ask, 'What was the trigger?'" she says. "If you haven't done anything differently, then have it looked at. I'm a huge believer in gut feelings.''
None of this means giving up the Internet entirely; after all, it is one of the most incredible medical resources in the history of mankind, Horvitz says. But stick with research-based sites.
A study by the Pew Internet and American Life Project 2007 reveals that although 80 percent of American adults have searched for health-care information online, 75 percent didn't always consider the validity of the source, which is research-speak for the fact that most self-diagnosers aren't questioning whether they can really get the most reliable health info from Dan's Lyme Disease Hut.
A final caveat, Horvitz adds: Stay off the message boards. Yes, they are a tremendous source of support for people who have already been diagnosed, but they are not a place to lurk while you're wondering about that twitch you've just developed: A forum of patients with ALS will be populated with sick people whose stories began with a single tremor.
"There's a high concentration of people with a very rare illness in a small place," Horvitz says, "so it seems common when you're looking at it."
Still, "I think it's important for people to feel free to investigate their own health, Sanders says. Googling is a way of expressing this very ancient desire that we all have, which is to seek meaning in suffering.
She recalls the 88-year-old patient who brought in a dossier to support her theory that she had a congenital displacement of the splanchnic nerve. (Her real problems were hypertension, osteo-arthritis, and diabetes.) Sanders couldn't bear to throw the files away. She says, "We all want to make the chaotic world of the body make sense."
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