CHICAGO — If you’re being treated for cancer, speak up about any side effects. A study that had patients use home computers to report symptoms like nausea and fatigue surprisingly improved survival — by almost half a year, longer than many new cancer drugs do.

The online tool was intended as a quick and easy way for people to regularly report complications rather than trying to call their doctors or waiting until the next appointment. Researchers had hoped to improve quality of life but got a bonus in longer survival.

The study was presented at the cancer group’s annual meeting in Chicago on Sunday and published in the Journal of the American Medical Association.

Earlier studies suggest that doctors miss about half of patients’ symptoms.