Single case design visual analysis procedures for use in practice evaluation

Visual procedures are the most commonly used in the analysis of single case design data. However, a number of problems with visual analysis methods ha ve been identified in previous research, and research and development on vi sual analysis methods has been recommended. If single case design methods a re to be used, as once hoped, by social work practitioners, then visual ana lysis methods should be easy and quick to use as well as methodologically d efensible. This article presents visual analysis methods fur use by social work practitioners. First, there is a presentation of a method for represen ting trend. Next there is a presentation of methods for representing variab ility, background variability, and overlap and discussion of their use in t he: visual analysis of single case data. Finally, there are two illustrativ e data analyses in which these methods are used. The mathematical and stati stical bases for these methods are provided in two appendices. The methods presented are quick and easy to use and require nothing more than a pencil or pen and a straight edge for use by practitioners.