The CAT score is a short patient-reported questionnaire measuring how much COPD symptoms are affecting a person's daily life, used to track symptom burden over time.
Low impact on daily life.
Medium impact.
High impact.
Very high impact.
CAT is purely symptom and quality-of-life focused and patient-reported. BODE combines objective measurements (BMI, FEV1, walk distance) with a symptom scale, making it more of a prognostic tool.
Roughly: under 10 is low impact, 10–20 medium, 21–30 high, and above 30 very high symptom impact on daily life.
It tracks symptom burden over time and helps gauge response to treatment. A change of about 2 points is considered clinically meaningful.
Eight — cough, phlegm, chest tightness, breathlessness, activity limitation, confidence leaving home, sleep, and energy — each scored 0–5 for a total of 0–40.