Researchers have demonstrated that placebos (such as sugar pills) can produce results similar to those of real drugs in patients with some conditions. Such results have a confirmed the hunch of many scientists that a patient’s belief in a treatment affects the outcome. But several factors make the interpretation of such findings (i)____; some people respond better to placebos than others for unknown reasons; some illnesses and afflictions are more (ii) _____ than others; and many of the most intriguing findings are (iii)______.