What do performance status scores 0 to 4 mean?
The commonly used ECOG or WHO scale runs from 0 to 4:
- PS 0: fully active, without restriction in usual activities;
- PS 1: able to manage usual light activities, but strenuous activity is limited;
- PS 2: able to look after yourself and up for more than half the day, but unable to work;
- PS 3: needing some help with personal care and in bed or a chair for more than half the day;
- PS 4: unable to manage personal care and in bed or a chair all the time.
These are broad clinical descriptions. People do not always fit neatly into one category, and the score should be assessed in context. A physical disability or another longstanding condition may affect activity without reflecting the effect of the cancer itself.
Why do oncologists assess performance status?
Performance status helps the team describe a person’s current level of function in a consistent way. It can contribute to decisions about:
- whether a treatment is likely to offer worthwhile benefit;
- how safely someone may tolerate treatment and its side effects;
- whether a dose, schedule or treatment approach needs adapting;
- eligibility for a clinical trial;
- how health and function are changing over time.
It is also one reason two people with apparently similar cancers may receive different treatment recommendations.
The score does not make the decision by itself
A particular score does not automatically mean that treatment should or should not be offered. The team also considers the cancer type and extent, the purpose and evidence for treatment, symptoms, other health conditions, organ function, previous treatment, possible alternatives and the person’s priorities.
Different treatments place different demands on the body. A performance status that is important for one treatment may not have the same implications for another. The balance can also be different when treatment is intended to cure cancer, control it, or relieve symptoms. The article on palliative cancer treatment explains how a non-curative treatment can still be active treatment.
Do not use a score from this page to decide for yourself whether you are eligible for treatment. If a performance status has affected a recommendation, ask the oncologist to explain how it was assessed and what other factors were considered.
Can performance status change?
Yes. Function may improve if symptoms are treated, an infection resolves, pain is controlled or cancer responds to treatment. It may worsen because of the cancer, treatment side effects or another illness. Clinicians can reassess it when the situation changes.
Performance status is therefore a description at a point in time, not a permanent label. When treatment has started, it may be considered alongside symptoms, examination, blood tests and scans as part of the wider assessment of whether treatment is helping.
Questions you can ask
- What performance status have you recorded, and what led to that assessment?
- How has it influenced the treatment recommendation?
- Are any reversible problems affecting my activity at present?
- Could the score or treatment options change if my general condition improves?
- What other factors were important in the decision?
Your clinical team can explain what performance status means in your particular situation and how much weight it carries in the decision being discussed.