performance status

Performance status is a simple score that captures how well a patient is able to carry out everyday activities — getting up, moving about, looking after themselves, working. It answers a practical question that test results alone cannot: how strong and functional is this person in real life, right now? In cancer care that answer can matter as much as the scan or the biopsy.

The most widely used scale, from the Eastern Cooperative Oncology Group (ECOG), runs from 0 to 5. A score of 0 means fully active with no restriction; 1 means restricted in strenuous activity but up and about; 2 means up more than half the day but unable to work; 3 means largely confined to a bed or chair; 4 means completely dependent; and 5 denotes death. A related scale, the Karnofsky scale, expresses much the same idea as a percentage.

Doctors lean on performance status because it strongly predicts how well someone is likely to tolerate and benefit from aggressive treatment. A fit patient may be offered surgery, full-dose chemotherapy, or intensive combinations, whereas someone who is very debilitated may be harmed more than helped by such treatments, and gentler, comfort-focused care may serve them better.

A fair caveat: the score is a snapshot and partly subjective, and it can improve once a treatable problem (such as pain, anemia, or the cancer itself) is addressed, so it is reassessed over time rather than treated as fixed.