While long-term care stakeholders often discuss how much Medicare money is spent on the terminally ill, a prominent researcher and columnist argues that much of conventional wisdom is wrong.

Howard Gleckman last week in Forbes noted a recent study that says only 5% of Medicare dollars are spent on those predicted to die, rather than the commonly quoted 25%. Part of the challenge is that even the best healthcare professionals cannot predict how much time their patients or residents have left, especially within a year timeframe.

“Using spending in the last year of life as a proxy for futile care is deeply flawed — because we are very bad at predicting who is going to die and who is not,” he writes. Hospice is based around patients expected to live six months or less, but many patients live longer. Yet others die within days, he noted. At the same time, the healthcare industry invests a lot of money in those who are sick, regardless of whether they are dying.

“In short, we should be looking to how much we spend on sick people, not how much we spend on people who die within some arbitrary time frame,” Gleckan writes. “If we are going to cure the medical cost growth problem, we first need to accurately diagnose the problem.”