Choosing and Using Single-System Design

Many people receive their first introduction tothe scientific method in their early school years. The first experimentswhich students undertake typically involve plants, chemicals, or smallanimals in a tightly controlled experimental environment. Theseexperiments enable students to establish a relatively clearcause-and-effect relationship between the outcome of the experiment andthe manipulation of the variables.

As soon asa researcher introduces a human element, proving a cause and effectrelationship becomes more difficult—as the researcher cannot enact totalcontrol of another person even in an experimental environment. Socialworkers serve clients in highly complex real-world environments. Clientsoften implement recommended interventions outside of social workers’direct observation. Yet, evidence-based research calls for socialworkers to establish cause-and-effect relations between selectedinterventions and client outcomes as much possible. To meet thischallenge, social workers must understand the study designs available tothem and all of the variations of that design that can increase therigor of the experiment and improve the likelihood of verifying acause-and-effect relationship.

In this week’scase study, you decide whether the social worker in the case study hasappropriately chosen a single-system (subject) design and implemented itin such a way that it can be considered an appropriate example ofevidence-based research.

To prepare for thisDiscussion, read the case study Social Work Research: Single Subject andcriteria for using single-system (subject) designs as evidence ofeffective practices in this week’s resources. Consider whether the studydesign described in the case study will serve the purpose of evaluatingthe program’s practice approach (case management with solution-focusedand task-centered approaches). Consider whether these approaches arewell suited to evaluation by the types of measurement used in the study.Consider to what objective measurement the numerical scales used tomeasure problem-change and task completion corresponds. Consider whatnew knowledge and evidence for the efficacy of the treatment approachesChris has generated with her study.

By Day 3

Post an evaluation of theproposed study design described in the case study file. Explain whetherthe outcome of Chris’ study with her client George would lead you toadopt the model of case management with solution-focused andtask-centered approaches, and substantiate your choice. Providerecommendations for improvements should Chris and her colleagues wish tosubmit the study to the evidence-based practice registry. Include arationale for your recommendations.