External validation of the number of risk factors score in a palliative care outpatient clinic at a comprehensive cancer center.

Background: Prognostic tools are available to predict if terminally ill cancer patients have days or weeks to live. Tools for predicting the prognosis in ambulatory patients at an earlier stage are lacking. The Number of Risk Factors (NRF) score developed in ambulatory cancer patients receiving palliative radiation therapy may be suitable for this purpose but has not been tested in a palliative care setting.