University of Wisconsin-Madison sociologist Deborah Carr and Rutgers University colleague Dmitry Khodyakov say education, religious attitudes and experience with a loved one's death -- especially a painful death -- are all powerful influences on end-of-life decisions.
Fifty-three percent of the random subsample of more than 7,000 Wisconsin Longitudinal Study participants said they had named a healthcare proxy, according to the study published in the Journal of Health and Social Behavior.
People who had attended some college or had a college degree were more likely than high school graduates to have a "durable power of attorney for healthcare" to make healthcare decisions for the patient.
While the overwhelming majority turn to either a spouse or child, the researchers recorded more than 25 different choices to ensure one's wishes for end-of-life medical treatment including siblings, co-workers, clergy and physicians.
Notable deaths of 2014 [PHOTOS]
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