Evidence-Based Case Study Guidelines for Couple and Family Psychology®
The clinical case study may be defined as a detailed analysis of the therapy conducted with a couple or family that will be instructive, may be exemplary or cautionary, and stresses factors contributing to either success or failure of the treatment. Because evidence-based clinical case studies can be difficult to do well, the following guidelines are provided:
1. The case study report should include several outcome measures assessing functioning across multiple domains, as well as relevant process measures evaluated at multiple times across treatment.
At minimum the case study report should include the following:
- A standardized measure of family/couple functioning from the perspective of the couple/family;
- A standardized outcome measure of global functioning;
- A standardized outcome measure of the target symptom (i.e. depression, marital conflict, parenting stress, child behavior); and
- One process measure (i.e. therapeutic alliance) evaluated on at least three separate occasions during treatment.
2. Specific outcome data should be presented with consideration of clinically significant change methodology (Jacobson et al., 1999).
Three questions (further explained below) should be addressed:
- At the end of treatment did the couple/family end up in a range that renders them indistinguishable from non-clinical or well-functioning couples/families?
- Was the magnitude of the change sufficient to be meaningful, i.e. statistically reliable, as determined by the Reliability Change Index (RCI)?
- What clinical outcome status may be concluded from the data?
Patients may be considered to have moved to the well-functioning range if their pre-treatment scores fell within the clinical range but have shifted post-treatment to the nonclinical range as defined by the measure employed.
The RCI is equal to the individual's score before intervention minus their score after intervention then divided by the standard error of the difference of the test(s) being used. If the RCI is greater than 1.96, then the difference in the scores would be considered to be significant. Calculation of the RCI can be done by hand; however, programs to assist are readily available. See Reliable change criterion calculator, for example.
Outcome status may be considered Recovered, Improved but not Recovered, or Deteriorated at the end of treatment.
- Recovered classification is appropriate when at the end of treatment clients' score within a range that is considered nonclinical, and the magnitude of change (RCI) is reliable.
- Improved but not Recovered classification is appropriate when the client shows statistically significant change (RCI) but ends therapy still somewhat dysfunctional as measured on post-test scores.
- The Deteriorated classification is appropriate when post-treatment scores drop within or into the clinical range and the deterioration is of reliable magnitude. Score changes that are not of reliable magnitude should not be deemed clinically significant change.
3. Clinical significance methodology is often discussed in the literature in terms of individual pre-post treatment scores consistent with individual treatment. Couple and family assessment and therapy present the challenge of measuring clinically significant change in a dyad or a group of family members. Case study authors may average scores to present couple or family-wide clinically significant change or may present individual family member change scores.
It is appreciated that in a multi-member system couple or family-wide change can be difficult to achieve. Clinically significant change in the target symptom and some, but not all, individuals should not be viewed to invalidate the instructional value of the case study. In this situation, however, the author may wish to categorize the outcome of the couple/family as Improved but not Recovered.
4. Submission of both successful and unsuccessful treatment cases is encouraged. In addition, it might be quite instructive to compare and contrast the technical interventions that occurred during a positive change case with that of a clinically unchanged or deteriorated case using the same approach to treatment.
5. Verbatim clinical dialogue between the couple/family and therapist highlighting key interventions and mechanisms of change and that highlight the specific approach to treatment should be provided. Discussion of therapeutic interventions should not be presented from a global or abstract perspective.
6. Appropriate informed consent must be obtained from clients prior to case study submission.
For further reading on clinical significance methodology:
- Jacobson, N., Roberts, L., Berns, S., & McGlinchey, J. (1999). Methods for defining and determining the clinical significance of treatment effects: Description, application, and alternatives. Journal of Consulting and Clinical Psychology, 67, 300–307.
- Jacobson, N.S. & Truax (1991). Clinical Significance: A statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology, 59 (1), 12–19.