Findings from a recent clinical trial validate patients as a crucial source of evidence in cancer research. The trial investigated patients with non-small cell lung cancer (NSCLC) receiving chemotherapy plus standard- or high-dose radiotherapy. The high-dose arm of the trial was eventually closed, because its patients had shorter survival than those treated with standard-dose radiation. Notably, health care providers had not reported higher toxicity in high-dose patients. However, patients in this group had reported lower quality of life than those in the standard-dose group, suggesting that patient feedback can pinpoint treatment effects not captured by provider reports. Patients also reported a higher quality of life with intensity modulated radiation therapy (IMRT) than with three-dimensional conformal radiation therapy (3-D CRT).