Systematic review of Goal Attainment Scaling as an outcome measure in drug trials

Goal Attainment Scaling (GAS)[1] is a technique aimed to measure change induced by treatment. GAS enables patients to set goals and to determine the relative success in achieving these goals on a 5-point scale that is precisely defined beforehand. Since the goals are individually determined, goals may differ in actual content. Its individual and patient oriented approach is one of the appealing aspects of GAS when used as an outcome measure for trials, particularly in orphan diseases. GAS may be more responsive than standardised questionnaires, making it useful in smaller and more heterogeneous samples. In this systematic review, we aim to investigate whether the measurement properties of GAS have been evaluated in drug trials.