Research physicians face intractable dilemmas when they consider introducing new medical procedures. Innovations carry the promise of preventing or curing life-threatening diseases, but they can also lead to injury or even death. How have clinical scientists made high-stakes decisions about undertaking human tests of new medical treatments? In Lesser Harms, Sydney Halpern explores this issue as she examines vaccine trials in America during the early and mid-twentieth century. Today's scientists follow federal guidelines for research on human subjects developed during the 1960s and 1970s. But lo.