"None of these things are backed by much evidence," said Halpern, who, in addition to the M.D., has a Ph.D in epidemiology and a master's in bioethics. While there is scientific support for outpatient palliative care programs, the evidence is weaker for the burgeoning number of inpatient programs, he said. He is most critical of POLST (Physician Orders for Life-Sustaining Treatment) programs because they are inflexible and illness is unpredictable.