Off-campus UMass Amherst users: To download campus access dissertations, please use the following link to log into our proxy server with your UMass Amherst user name and password.

Non-UMass Amherst users: Please talk to your librarian about requesting this dissertation through interlibrary loan.

Dissertations that have an embargo placed on them will not be available to anyone until the embargo expires.

Access Type

Campus-Only Access for Five (5) Years

Document Type


Degree Program


Degree Type

Master of Science (M.S.)

Year Degree Awarded


Month Degree Awarded



Aim: A randomized clinical trial demonstrated that responsively adding motivational interviewing (MI) to cognitive-behavioral therapy (CBT) for generalized anxiety disorder (GAD) outperformed CBT alone on long-term worry reduction (Westra et al., 2016). Consistent with MI’s additive aim, this effect was mediated by less patient midtreatment resistance in the integrative treatment (Constantino et al., 2019). Insofar as GAD is marked by interpersonal styles of excessive nonassertiveness and over accommodation, I tested here whether MI-CBT also outperformed CBT, across acute treatment and long-term follow up, on reducing these characteristic interpersonal problems. Moreover, as patient resistance is an interpersonal event for which person-centered MI should, according to theory, be more helpful than directive CBT, I tested if resistance also mediated the expected effect of treatment on the long-term interpersonal outcomes. Method: Eighty-five patients with severe GAD were randomly assigned to 15 sessions of MI-CBT or CBT. Patients completed a measure of interpersonal problems repeatedly through treatment and 12 months of follow up. Independent observers rated patient resistance at a midtreatment session. Results: As expected, structural equation models revealed comparable reductions in nonassertiveness and over accommodation across acute MI-CBT and CBT. Also as predicted, MI-CBT vs. CBT promoted significantly greater reduction in over accommodation problems over long-term follow up; however, this differential effect was only marginally significant for nonassertiveness problems. Finally, as predicted, the treatment effect on the level of both interpersonal problems at 12-month follow up was mediated by less midtreatment resistance in MI-CBT vs. CBT. Discussion: Results support that the benefit of adding MI to CBT for GAD extends to long-term interpersonal change, and they implicate resistance management as a candidate mechanism of this additive effect.


First Advisor

Michael J. Constantino