The PPI predicts survival in terminally ill oncologic patients based on the score in the Palliative Performance Scale, and four other clinical symptoms: oral intake, oedema, dyspnea at rest and delirium:

Palliative Performance Scale: 10-20 (+4), 30-50 (+2.5),>60 (0);
Oral Intake: Severely Reduced (< mouthfuls) (+2.5), Moderately Reduced (> mouthfuls) (+1), Normal (0);
Oedema: Present (+1), Absent (0);
Dyspnea at rest: Present (+3.5), Absent (0);
Delirium: Present (+4), Absent (0).

The PPI can acceptably predict whether or not a patient will survive >3 or >6 weeks.

PPI results range from 0 to 15 with the indication that scores greater than 6.0 survival is less than three weeks (Sensitivity - 80%; Specificity - 85%).

The existence of concomitant diseases has not been taken into account in the building of the majority of survival prognostic scores, although acute concomitant diseases can impact scoring and survival.