The extent to which a quality-of-life instrument can detect small but clinically important changes with a subject, usually a patient.
Responsiveness is concerned with the calculation of key changes in health and is applicable when instruments are part of the process for the evaluation of health outcomes.
No single method of assessing responsiveness is officially acknowledged, with various statistical techniques being used for quantifying responsiveness.

See also:
Quality of life (QOL)
Clinical
Quality of life trials