A recent Journal of General Internal Medicine survey revealed that one third of married couples don't automatically select their spouse to make medical decisions for them, and those who chose a different person opted for a female family member by a substantial margin. According to MarketWatch, the married couples who didn't choose their spouse did so because they knew someone with more medical knowledge, didn't want to burden their spouse with difficult decisions, or disagreed with their spouse on when to stop life support. Approximately 29% of respondents selected their parents as their medical proxy, and in that instance they chose their mother over their father by a margin of five to one. For children, daughters were preferred over sons three to one, and for siblings, sisters were picked over brothers two to one. However, if the male counterpart had more medical experience, such as a son who is a doctor, they were likely to be chosen as proxy.