What is the purpose of a goal line in a single-case design line graph?

The purpose of a goal line in a single-case design line graph is to serve as a visual reference for client progress toward an objective. This line represents the desired outcome or target that the client aims to achieve throughout the intervention. By plotting this goal line alongside actual data points collected during the intervention, practitioners can clearly see how much progress a client is making in relation to the established goal. It helps to facilitate a more straightforward analysis of effectiveness because any shifts in client performance can be evaluated against this established point of reference.

In this context, the goal line does not indicate a specific time frame for achieving objectives nor does it represent baseline data of the client. Additionally, it does not show the maximum possible outcome measure, as its primary function is to track progress toward a specific goal rather than to set benchmarks for the highest potential outcomes.