The association between the therapeutic alliance and long-term outcome in a guided Internet intervention for depressive symptoms

BACKGROUND: The therapeutic alliance has been well established as a robust predictor of face-to-face psychotherapy outcome. Although initial evidence also positioned alliance as a relevant predictor of Internet interventions’ success, some conceptual and methodological concerns were raised regarding the methods and instruments used to measure the alliance in Internet interventions and its association with outcome. OBJECTIVE: The aim of this study was to explore the alliance-outcome association in a guided Internet intervention using a measure of the alliance especially developed for and adapted to guided Internet interventions, showing evidence of good psychometric properties. METHODS: A sample of 223 adult participants with moderate depression were treated with an Internet intervention (i.e., deprexis) and e-mail support. They completed the Working Alliance Inventory for guided Internet interventions (WAI-I) and a measure of treatment satisfaction at treatment termination and measures of depression severity and well-being at termination as well as at 3- and 9-months follow-up. For data analysis, we used two-level hierarchical linear modeling, including the two subscales of the WAI-I (i.e., Tasks and Goals agreement with the program and Bond with the supporting therapist) as predictors of the estimated values of the outcome variables at the end of follow-up and their rate of change during the follow-up period. The same models were also run controlling for the effect of patients’ satisfaction with treatment. RESULTS: We found significant effects of the Tasks and Goals subscale of the WAI-I on the estimated values of the residual depressive symptoms, γ02 = -1.74, SE= 0.40, CI95[-2.52, -0.96], t(206)= -4.37, p < .001, and patient’s well-being, γ02 = 3.10, SE= 1.14, CI95[0.87, 5.33], t(198)= 2.72, p = .007, at the end of follow-up. A greater score in that subscale was related to lower levels of residual depressive symptoms and a higher level of well-being. However, there were no significant effects of the Tasks and Goals subscale on the rate of change during follow-up in these variables. The effects of the Bond subscale were also non-significant when predicting the estimated values of depressive symptoms and well-being at the end of follow-up and the rate of change during that period. CONCLUSIONS: The results of this study point out the importance of attuning Internet interventions to patients’ expectations and preferences in order to enhance their agreement with the tasks and goals of the treatment. Thereby, the results support the notion that responsiveness to the patient’s individual needs is crucial also in Internet interventions. Nevertheless, these findings need to be replicated to establish if they can be generalized to different diagnostic groups, Internet interventions, and supporting formats