QALYt
QALYt is a proposed extension of the quality-adjusted life year (QALY) metric that explicitly incorporates time as a variable. In this framework, the health utility u(t) is allowed to vary over a specified time horizon, capturing changes in health status due to disease progression, treatment effects, adverse events, and recovery. The t in QALYt denotes time, making the measure sensitive to when quality of life changes occur within the evaluation period. As a theoretical concept, QALYt aims to support decision making for interventions with dynamic health trajectories.
Calculation of QALYt typically involves integrating the time-dependent utility over the chosen horizon. In continuous form,
Data and modeling for QALYt rely on longitudinal quality-of-life measurements and methods to map health states
QALYt has potential applications in chronic diseases, oncology, and conditions with fluctuating health states, but it
See also: quality-adjusted life year, health economics, cost-utility analysis, health-state utilities, discounting.