How to Evaluate a Tailor-made Social Work Intervention? Some Practice-Based Solutions with Single-Case Designs.

Purpose: With the increased attention to the principles of evidence-based practice (EBP), social workers are challenged to adapt their daily interventions accordingly when treating clients. They usually work with individual clients, all with their own specificities. Single-Case Experimental Designs (SCEDs) can be used to inform a social worker about the effectiveness of an intervention at the individual client level. In everyday social work practice, however, it is difficult to meet methodological requirements of SCEDs to find causal explanations. A concern is that repeated measurements prior to an intervention are required in most situations. This study aims to provide researchers with alternatives to repeated measurement when using the logic of SCED to apply EBP in their everyday practice.

Methods: In this study, we reviewed published single-case designs between January 1 and December 31, 2019, on types of SCEDs in the social domain, and how is dealt with baseline conditions.

Results: SCEDs and quasi-experimental alternatives are hardly published in situations when baseline data are not available. Four underused quasi-experimental strategies that can be employed when repeated measurement during baseline is not possible are as follows: retrospective baselines, theoretical inference, multiraters, and triangulation with qualitative data.

Discussion and conclusion: The suggestions to work with single-case designs with quasi-experimental elements are meant to enable social workers to evaluate their interventions in a way that enhances mere narrative evaluations of the experiences of an intervention.