Would you make a different decision about having a feeding tube if you'd been in a car accident than if you were faced with increasingly severe dementia?

On Jan. 1, the new Utah Advance Health Care Directive Act goes into effect as the tool to express personal choices regarding health care if you are unable to speak for yourself. Advocates for the bill, passed by the 2007 Legislature, say it greatly improves the likelihood an individual's preferences will be honored when it comes to health-care decisions.

Among other things, the act:

• Uses a single form instead of three.

• Lets you select "triggering conditions" for treatment or non-treatment choices.

• Lets you pick an agent to speak for you and gives that person more authority, although you can decide if that person must honor what you wrote or can make decisions based on the situation.

• Emphasizes your constitutional right to make your own decisions if you want, even if your doctor says you're not capable. Only a court can override that.

It does not require, as the current law does, that a person be "terminally ill or in a persistently vegetative state" before it takes effect. That's important, proponents say, because most conditions a person might have that call for a spokesman/decisionmaker may not meet that definition.

A health-care provider can withdraw from a case for "reasons of conscience." And those who follow the directive are protected from civil or criminal liability.

Individuals can pick and choose which parts of the form they want to fill out. It's easily changed or revoked, and if you can communicate, you can override it at will.

It's not easy to predict the future, as the instructions and forms booklet note. "Don't keep me alive on machines" may be what you want if you needed mechanical support such as a ventilator to keep you alive for the rest of your life. But if being on a ventilator for a few days would let you go home from the hospital, breathing on your own and as healthy as you were before you were hospitalized, you might want to be kept alive on machines until you are better," the guide says. "Some people live satisfying lives even when they depend on 'machines.'

"Advance health care planning is harder and more complicated than you may think." And, it adds, "written directions are usually worse decision-makers than an agent" because of that inability to predict the future. It's important, it says, to talk about different situations with the person you want to have as your agent.