More broadly, and despite the fact that most people will eventually find themselves in a situation in which they cannot make their own decisions, 46 percent of the population have not discussed with anyone how they would want to be cared for should they become incapacitated. That includes most men, people of color, and those without college education.

55 percent haven't taken the initiative to name a health care proxy to make those decisions for them. Yet a third of Massachusetts residents who had a loved one die in the past year said patient preferences were not fully followed, and one-fifth described the end of life care they witnessed as only fair or poor, which should be a wake-up call.

The good news is that when people actually went so far as to name a health care agent, 85 percent talked to their agent about their wishes if faced with serious illness.

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"This is about how you want to live, not just about how you want to die," Atul Gawande, M.D., M.P.H., co-chair of the Coalition and executive director of Ariadne Labs, a joint center of Brigham and Women's Hospital and Harvard T.H. Chan School of Public Health, says in a statement.

Gawande continued, "When clinicians don't talk to people about their priorities for serious illness care, care can become misaligned with what matters to them. And the result is suffering."