It could be a health marketer's worst nightmare-- or a dream come true. The "know-it-all" patient has arrived on the internet. HealthCentral Network's GM has the story.

The Pew Internet & American Life Project has just released an update of its landmark 2002 survey of the behavior of online health seekers, and it demonstrates that a new kind of patient may be emerging who will alter the balance of traditional health care.

Pew's Report shows that more that 80 percent of Americans comb the web for health information-- nearly 10 million in a typical day. And these health seekers like what they are finding. More than half report that the information affected a decision about a treatment for a disease or condition, changed their overall approach to maintaining their health and led them to ask new questions of their doctor or seek a second opinion.

Health information on the web not only informs, but empowers. The study showed that more than half surveyed said they felt more confident about raising new questions, relieved by the information they found, and eager to share their new-found knowledge with others.

The biggest statistic to emerge from the study is that nearly three quarters of online health seekers reported that, after their online quest, they felt "reassured that they could make appropriate health care decisions."

The simple notion that patients are making decisions about their health is in fact a radical one, and it demonstrates the dramatic shift that has taken place in how we care for ourselves and our loved ones. In the old days, people went to their doctors to find out the causes and cures of their symptoms. These days, a doctor is still the best place to go for health care, but the relationship has subtly and profoundly shifted.

This shift has come about as we are being asked to become more and more responsible for our own care. Three factors have contributed to this trend. One is cost: As the price of health care rises, consumers are sharing more of the burden of deciding which aspects of care to get through systems such as Health Savings Accounts.

Two, medicine has evolved to the point that many diseases and conditions have a huge lifestyle component to them: how you live your life affects how long you'll live.

The third factor is what you might call the "Generation Net" effect. Boomers grew up demanding and getting what they want when they want it-- they like being in control. Younger generations who have grown up with the web take being in control for granted. Now that Boomers are growing old -- and encountering health problems -- they are turning to the ultimate control machine to get the information they need to act. 

The web has let the genie of "consumer control" out of the bottle: this has already profoundly changed media, communication and social networks, and now it is health care's turn. Savvy doctors are aware of this change and embrace "know-it-all" patients who want to take an active part in their care. "A physician is most effective when he or she isn't defensive, but acts as an interpreter of information," says Marc Siegel, an internist and Associate Professor of medicine at the New York University School of Medicine, "leaving the ultimate control to the patient."

For health care marketers and information providers, the "know-it-all" patient provides a huge opportunity-- and a huge challenge. Medicine, devices and information play a crucial role in people's health, and consumers are actively seeking knowledge, making decisions, and changing their behavior based on what they find online.

But search engine rankings, word-of-mouth through social networks, and the web's consummate transparency means that snake-oil cures will have a hard time thriving in this new world.

Ceding power and control to consumers may take some getting used to. But we have no choice.

Bill Allman is general manager and chief content/creative officer, The HealthCentral Network. Read full bio.