Alliance by treatment effects in generalized anxiety disorder.

The therapeutic alliance is often regarded as the quintessential common factor.

However, methodological limitations of research to date make it unclear whether alliance truly operates in a uniform manner across time in disparate psychotherapy treatment approaches.

This study examines the course of alliance across two manualized treatments, Cognitive-Behavioral Therapy (CBT) and Interpersonal/Emotional Processing Therapy (IEP) for Generalized Anxiety Disorder, administered concurrently to the same clients by the same therapists in an additive design.

Findings suggest that therapist-rated alliance was slightly higher in CBT than IEP and increased linearly over time for both treatment approaches.

Client-rated alliance failed to show a treatment type, phase, or type-by-phase interaction.

Results are discussed in terms of common factors theory, research on temporal patterns of alliance, and treatment-specific effects.

Limitations and future directions are also discussed.