Separating the effects of alliance ruptures and improvements on outcome session-by-session using the asymmetric fixed-effect model

Objective: The aim of this paper was to introduce the Asymmetric Fixed Effects model to psychotherapy mechanisms of change researchers as a novel way of studying the effects of improvements and deteriorations in the candidate mechanism(s) separately. Alliance-outcome research was used to illustrate the possibility of estimating separate effects of improvements and deteriorations in the alliance Method: Two archival datasets were used. One was from community-based primary care services in Sweden using theClinical Outcomes in Routine Evaluation — Outcome Measure (CORE-OM) and the Working Alliance Inventory—Short form (WAI-S, therapist form) each session with 1096 patients. The other dataset was from a university counseling center in China using the Session Rating Scale (SRS) and the Outcome Rating Scale (ORS) each session with 292 patients. Data was analyzed using the asymmetric fixed-effects model. Results: The findings indicated that with raw scores, improvements in alliance from one session to the next were followed by lower symptoms/distress scores by the next session, but alliance deteriorations had no effect on next-session symptoms/distress. With alliance deteriorations and improvements defined relative to the sample’s average linear change over time, improvements and deteriorations had equal but opposite effects on next session symptom level. Conclusion: Findings confirm the utility of the Asymmetric Fixed Effect model across two cross-national samples in showing that alliance deteriorations and improvements can predict next session symptoms separately at the within-person level. Findings raise new questions regarding the use of detrending in within-patient mechanism of change studies