@Article{info:doi/10.2196/16660,
author="Miloff, Alexander
and Carlbring, Per
and Hamilton, William
and Andersson, Gerhard
and Reuterski{\"o}ld, Lena
and Lindner, Philip",
title="Measuring Alliance Toward Embodied Virtual Therapists in the Era of Automated Treatments With the Virtual Therapist Alliance Scale (VTAS): Development and Psychometric Evaluation",
journal="J Med Internet Res",
year="2020",
month="Mar",
day="24",
volume="22",
number="3",
pages="e16660",
keywords="alliance; virtual reality; exposure therapy; automated treatment; psychometric; embodiment; virtual therapist; virtual coach; avatar; usability; presence; empathy",
abstract="Background: Automated virtual reality exposure therapies (VRETs) are self-help treatments conducted by oneself and supported by a virtual therapist embodied visually and/or with audio feedback. This simulates many of the nonspecific relational elements and common factors present in face-to-face therapy and may be a means of improving adherence to and efficacy of self-guided treatments. However, little is known about alliance toward the virtual therapist, despite alliance being an important predictor of treatment outcome. Objective: In this study, we aimed to evaluate the first alliance instrument developed for use with embodied virtual therapists in an automated treatment format---the Virtual Therapist Alliance Scale (VTAS)---by (1) assessing its psychometric properties, (2) verifying the dimensionality of the scale, and (3) determining the predictive ability of the scale with treatment outcome. Methods: A psychometric evaluation and exploratory factor analysis of the VTAS was conducted using data from two samples of spider-fearful patients treated with VRET and the help of an embodied, voice-based virtual therapist (n=70). Multiple regression models and bivariate correlations were used to assess the VTAS relationship with treatment outcome, according to self-reported fear and convergence with presence and user-friendliness process measures. Results: The VTAS showed a sound two-factor solution composed of a primary factor covering task, goal, and copresence; adequate internal consistency; and good convergent validity, including moderate correlation (r=.310, P=.01) with outcomes over follow-up. Conclusions: These preliminary results suggest that alliance toward a virtual therapist is a significant predictor of treatment outcome, favors the importance of a task-goal over bond-factor, and should be explored in studies with larger sample sizes and in additional forms of embodiment. ",
issn="1438-8871",
doi="10.2196/16660",
url="https://www.jmir.org/2020/3/e16660",
url="https://doi.org/10.2196/16660",
url="http://www.ncbi.nlm.nih.gov/pubmed/32207690"
}