To help prevent overtesting and overtreatment of older patients — or undertreatment for those who remain robust at advanced ages — medical guidelines increasingly call for doctors to consider life expectancy as a factor in their decision-making. But clinicians, research has shown, are notoriously poor at predicting how many years their patients have left.

Now, researchers at the University of California, San Francisco, have identified 16 assessment scales with “moderate” to “very good” abilities to determine the likelihood of death within six months to five years in various older populations. Moreover, the authors have fashioned interactive tools of the most accurate and useful assessments, and posted the interactive versions at a new Web site called ePrognosis.org, the first time such tools have been assembled for physicians in a single online location.