Abstract

A within subjects, multiple baseline across participants design was implemented to assess the effectiveness of progressive muscle relaxation skills in reducing anxiety in three adults with mild intellectual disability and Generalized Anxiety Disorder. The study's design included a four-week (minimum) baseline period, followed by a criterion-based intervention, and four weeks of follow-up beginning one month after the completion of the intervention. Participants were taught progressive muscle relaxation skills during individual meetings with the primary investigator. Skill training occurred two times per week with sessions typically lasting 30-45 minutes. Dependent measures included direct observation of skill development (number of progressive muscle relaxation skills learned), self-reported anxiety ratings (Self-Report Inventory Anxiety Subscale), and informant reported anxiety ratings (Behavior Rating Scales Anxiety Subscale). In addition, measurements of immediate anxiety and relaxation occurred twice each session to assess within session changes in these areas. The results of the study provide support for the use of progressive muscle relaxation skills in treating symptoms of Generalized Anxiety Disorder in adults with mild intellectual disability. A direct relationship was evident between the acquisition of progressive muscle relaxation skill development and reduction in anxiety for all participants. Within session changes in anxiety and relaxation ratings revealed immediate reductions in anxiety and increased relaxation after the implementation of progressive muscle relaxation skills. Furthermore, progressive muscle relaxation skills were maintained at near perfect to perfect levels at 1-month follow-up, while ongoing reductions in anxiety were noted.