64 Assessment, Evidence-Guided Practice, and Practice Evaluation environment like teachers and parents also can be used to establish a baseline (to assess a student’s behavior in the classroom or child’s behavior in the home, respectively). Four dimensions of the intervention itself (the independent variable) can be measured: form, content, dosage, and context. The process of the single-subject design is rarely as straightforward as the model suggests. Three factors explain this: changes in clients’ environment that may explain changes in the clients’ lives difficulties in measuring more subtle aspects of the intervention, like the working relationship itself and the challenges associated with quantifying each aspect of the intervention and accounting for changes that occur in response to changing views of the stress- ors, focus of the work, and other elements. The assessment that worker and client establish provides a means for evalu- ating the outcome of their work together. Goal attainment scaling requires that the worker and client describe the best and worst possible outcomes of their work together, as well as three points in between. At the conclusion of their work, they can use this scale to ascertain clients’ progress. Task achievement scaling assesses the extent to which the worker and cli- ent have performed the tasks required to accomplish clients’ goals. Like goal attainment scaling, the worker and client define the two end points (completely achieved and no progress), as well as three points in between. Competency 9: Evaluate Practice with Individuals, Families, Groups, Organizations, and Communities • Select and use appropriate methods for evaluation and outcomes. • Apply knowledge of human behavior and the social environment, person-in- environment, and other multidisciplinary theoretical frameworks in the evaluation of outcomes. • Critically analyze, monitor, and evaluate intervention and program processes and outcomes. • Apply evaluation findings to improve practice effectiveness at the micro, mezzo, and macro levels. 8. Evidence-Guided Practice: Cautionary Notes Rapid assessment instruments provide guidance to workers and clients as they determine the focus of their work, as well as acting as a means of assessing the outcome of this work. Workers must be judicious when using these instru- ments and consider issues such as clients’ literacy and an instrument’s cultural relevance. Workers also must not lose sight of the fact that clients’ responses