The first video in Pew Research Center’s Methods 101 series helps explain random sampling – a concept that lies at the heart of all probability-based survey research – and why it’s important. Fresh ...

Patients in two acute care university hospitals were entered into the study using the following method: twenty patients were selected each day from all floors/units in each hospital until the hospital ...

Not only is breast cancer more than one disease, but a single breast cancer tumor can vary within itself, giving the potential for very different patient treatment plans depending on the tumor sample ...