ABSTRACT
Visual analysis of graphed data, in contrast to statistical analysis of data, is the cornerstone of and most frequently used data analysis method in single case design (SCD) research, particularly for determining whether a study demonstrates experimental control. Visual analysis involves systematic procedures used to evaluate specific characteristics of data patterns and evaluate the presence of a functional relation. Visual analysis involves both formative and summative evaluation. Formative visual analysis is conducted within and across conditions to identify behavior change during the course of a study. Behavior change occurs when data patterns in one condition are different from data patterns in the subsequent, adjacent condition for the same variable(s). Visual analysis can be used throughout a study to make informed decisions or changes about design and study variables while maintaining experimental control and producing improved outcomes. Summative visual analyses are used to draw conclusions about the presence of functional relations and the magnitude of change.
