[1] GAS was first developed by Thomas Kiresuk and Robert Sherman in response to the wide variety of evaluation models regarding mental illness and treatment.
At least two points on the scale should have sufficiently precise and objective descriptions so that anyone could understand the client's status.
This allows qualitative data to be quantified in relation to the success of the client in achieving expectations of change.
Each scale is specific to the individual, and the defined points are indirectly related to mental health goals.
This goal-oriented measurement tool creates specific operational indicators of progress and can focus case planning and treatment.
GAS results in specific goal attainment indicators, making effectiveness readily apparent.
[8] GAS combines behavioral definitions, mutually defining goals, clear expectations, and continuous evaluation to improve client outcomes and effectively measure change.