If there was a tool that could tell you how long an elderly loved one had to live, would you use it?

Recent research has shown that many elders want to know in advance when they are going to die.

Survey results from dozens of elderly people grappling with a variety of different diseases and in a long-term care program indicated that 75% wanted to their doctor to tell them if they only had a year to live. The number dropped to 65% when the elders were given a diagnosis of less than five years.

According to the study authors, many seniors desire to have a discussion with their doctor about their prognosis because they want time to plan for their future medical care and maximize the time left to them.

The study was conducted by researchers from the University of California, San Francisco and the San Francisco VA Medical Center and was published in the Journal of General Internal Medicine.

Well, since you asked…

For those that want to know, a few different tools, developed by statisticians and doctors, claim to be able to help give you ballpark estimates of how long you have left to live.

Websites like ePrognosis.org, and the University of Pennsylvania "Life Calculator," offer to help predict a person's life expectancy and are both currently open to the public for free.

The "Life Calculator" allows people of any age to input information on their lifestyle habits, family history, and stress levels. ePrognosis offers a narrower window of applicability, offering disease and lifestyle-based predictions only for the elderly.

Dean Foster, PhD, a statistics professor at the University of Pennsylvania, Wharton School of Business, and co-creator of the "Life Calculator," says that though he and his colleagues built their tool several years ago, their method of basing predictions primarily on a person's age, sexual habits, and smoking habits, remains relevant even in light of current research.

ePrognosis.org was created by several of the same UCSF researchers that conducted the study examining senior's preferences about knowing their life expectancy prospects. The site allows people to choose from 16 different guides to help them determine the likelihood of a person dying within a certain period of time.

Over 21,000 different research studies were examined to come up with the 16 guides (also called indices) that are included on the site.

The website itself is clearly geared towards the physician, but can be used by anyone connected to the internet—including seniors and their caregivers.

Eric Widera, M.D., an assistant clinical professor at UCSF and one of the creators of ePrognosis.org, says that the decision to make the website public was a "point of tension" for its authors.

Accuracy counts

As intriguing as the idea of knowing how long you or a loved one has left to live may seem, experts advise caution.

Mindy Greenstein, PhD, a clinical psychologist who specializes in the treatment of cancer patients feels that prognosis websites aren't accurate enough to be helpful for caregivers or seniors, "Just because a website or test gives an answer, doesn't mean that answer is correct, nor does it mean there's any way of knowing whether it's correct."

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She says that there is no way of knowing how precise these sites are, pointing out that even doctors, who know the specific details of their patient's condition, don't always get it right.

Foster acknowledges that complete accuracy cannot and should not be guaranteed with regards to life expectancy tools. "The hallmark of a good system is that it gives ranges or probabilities. This is all good science can tell us. So if it is more accurate than that—it is bogus."

His sentiments are echoed by Widera, who cautions that, for patients and doctors alike, the projections on ePrognosis should be taken with a grain of salt. He says the site is only meant to be a "rough guide" to assist doctors—it should not be the only thing physicians and their patients use to make decisions about future care.

A false prognosis, whether given by a website or a doctor, has the potential to do serious psychological damage, according to Greenstein. A false timeline can cause unnecessary anxiety and lead to reckless decisions regarding a senior's future plans.

Widera urges curious caregivers and seniors to consult with a doctor before going on the website. The predictive indices that websites like ePrognosis and the "Life Calculator" are based on are created from generalized research and won't be applicable to each individual person.