Goal Attainment Scaling
Also known as: GAS, Goal Attainment Scale, Kiresuk-Sherman Goal Attainment Scaling, Individualized Goal Scaling
Goal Attainment Scaling (GAS) is a method for measuring the outcomes of an individualized intervention by writing, in advance, a small set of client-specific goals and defining for each a graded scale of possible outcomes from much worse than expected to much better than expected. After the intervention, the actual outcome on each goal is scored on this scale and the scores are combined into a single standardized index, allowing idiosyncratic, personally meaningful goals to be aggregated and compared across clients and programs. It was introduced by Thomas Kiresuk and Robert Sherman in 1968 to evaluate community mental health programs.
Key highlights
- Captures client-specific, personally meaningful goals while still producing a quantitative score that can be aggregated across very different clients.
- Responsive to change because the scale is built around the individual's expected trajectory, often detecting improvement that fixed instruments miss.
- The act of collaboratively defining goal levels is itself clinically useful, clarifying expectations and engaging the client in treatment planning.
- Applicable across an enormous range of fields and outcomes, from rehabilitation and mental health to education and organizational change.
Intuition
This section is available to Pro members. Upgrade to Pro
How it works
This section is available to Pro members. Upgrade to Pro
When to use it
Use Goal Attainment Scaling when intervention goals are genuinely individualized and a fixed, off-the-shelf scale would fail to capture what success means for a given client — common in rehabilitation, case management, mental health, geriatrics, and complex social work cases. It is valuable when you nevertheless need to aggregate outcomes across heterogeneous clients for program evaluation. It is less appropriate when goals are uniform across clients (a standardized measure is then simpler and more comparable), when staff cannot be trained to write balanced, realistic scales, or when the act of goal-setting itself would bias the outcome being measured.
Strengths & limitations
- Captures client-specific, personally meaningful goals while still producing a quantitative score that can be aggregated across very different clients.
- Responsive to change because the scale is built around the individual's expected trajectory, often detecting improvement that fixed instruments miss.
- The act of collaboratively defining goal levels is itself clinically useful, clarifying expectations and engaging the client in treatment planning.
- Applicable across an enormous range of fields and outcomes, from rehabilitation and mental health to education and organizational change.
- Validity depends heavily on the skill and consistency with which staff write the five outcome levels; poorly calibrated scales bias scores up or down.
- Setting the expected ('0') level too low or too high systematically inflates or deflates attainment, and there is no external benchmark to catch this.
- The T-score formula assumes a fixed inter-goal correlation and treats ordinal levels as interval data, assumptions that are debated.
- It measures attainment of the goals that were chosen, not whether the right goals were chosen, so a client can score well on trivial goals.
Common pitfalls
This section is available to Pro members. Upgrade to Pro
Applications
This section is available to Pro members. Upgrade to Pro
Frequently asked
How many goals should a GAS follow-up guide contain?
Most applications use between two and five goals. Too few goals make the overall score volatile — a single goal can dominate — while too many become burdensome to define and score reliably. Three is a common compromise that balances breadth of coverage against the practical effort of writing five well-calibrated outcome levels for each goal.
Why are outcomes scored on a -2 to +2 scale instead of a simple met/not-met judgment?
A binary met/not-met judgment loses information and is sensitive to where the threshold is set. The five-level scale, centered on the realistically expected outcome (0), records both shortfalls (-1, -2) and over-attainment (+1, +2), making the measure more sensitive to graded change and allowing the standardized T-score to reflect how far above or below expectation the client actually landed.
Is the GAS T-score a valid interval measurement?
This is debated. The T-score formula converts ordinal attainment levels into a 50/10 standardized scale and assumes a fixed correlation among goals, so strictly it is a transformation of ordinal data rather than a true interval measure. Many evaluators report the mean level score or use the T-score descriptively, and treat any parametric analysis of GAS outcomes with appropriate caution.
Sources
- 1.Kiresuk, T. J., & Sherman, R. E. (1968). Goal attainment scaling: A general method for evaluating comprehensive community mental health programs. Community Mental Health Journal, 4(6), 443–453.
- 2.Kiresuk, T. J., Smith, A., & Cardillo, J. E. (Eds.). (1994). Goal Attainment Scaling: Applications, Theory, and Measurement. Lawrence Erlbaum Associates.ISBN 9780805814040
You have read it. What now?
Cite this page
ScholarGate. (2026, June 22). Goal Attainment Scaling. ScholarGate. https://scholargate.app/social-work/goal-attainment-scaling