Unexpected dramatic changes in psychotherapy have been observed historically and tied to high recovery rates. Many different methodologies that identify these changes are assumed to be capturing similar or identical phenomena. This study compared three methods – Sudden Gains (SG), Percentage Increase – 50% (PI-50%), and Rapid Response (RR) - in a large database looking for similarities and differences. Results suggest that there are significant differences between SG, RR, and PI-50 as methods for operationally defining unexpected dramatic treatment response, and caution should be used when referring to SG, PI-50, and RR as the same phenomenon or interchangeable terms for unexpected dramatic treatment response. In particular, overlap in clients who experienced both a SG and RR was low. Experiencing any of the three phenomenon was associated with higher recovery rates, while differences abound in both which clients experience each of the phenomena and demographic characteristics of those clients. PI-50 identified inconsequential amounts of clients suggesting under its current methodological construction it would have limited useability. These results tying SG, RR, and PI-50 to significant rates of recovery and positive treatment change suggest possible future use as a predictive feedback tool for clients and clinicians alike to be better able to examine the effectiveness of treatment components during treatment.



College and Department

Family, Home, and Social Sciences; Psychology



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Psychology Commons