Goal Attainment Scale (GAS)

Goal Attainment Scaling is not a questionnaire. It is a method for turning a person's own goals into something that can be scored, so that progress on individualized aims can be compared across people and summarized statistically.

The therapist and client agree on two to four goals before intervention begins. For each, five levels are written out in advance, from much less than expected to much more than expected, with the middle level describing the outcome that is realistically expected. At follow-up, each goal is scored -2 to +2 against those written descriptions. Goals can be weighted by importance and difficulty, and the scores combine into a single T-score. A T-score of 50 means goals were met as expected.

• Turner-Stokes, Goal Attainment Scaling in Rehabilitation: A Practical Guide

Licensing Notes: Goal Attainment Scaling is a published method, not a proprietary instrument — originally described by Kiresuk and Sherman(1968). There is no license or fee.

Learn More: The baseline convention varies: some applications set every goal's baseline at -1 (or -2 where deterioration is possible) so that improvement is visible, while others treat -2 as the starting point by definition.