Most husbands and wives list each other as the person to make decisions about healthcare treatment if they become too sick to make their own wishes known. But new research shows that spouses very often don't know what their partners' wishes are.

A study from the University of Wisconsin of 2,750 married couples showed that 28 percent of the participants were incorrect when they guessed how their spouse would want to be treated if he or she were in severe pain and had a low chance for survival. Additionally, 14 percent didn't know their spouses' preference regarding cognitive impairment.

Many of the participants assumed that their spouses would have the same preferences that they themselves had. In other words, they didn't make a distinction between their own preferences and those of their spouse.

This points out the importance of discussing these issues with each other before problems arise. Many people find this difficult to do, but it's the best way to ensure that you'll receive the kind of care that you want to receive.