Reliability and validity of a videotape method to describe expressive behavior in persons with Parkinson's disease.

The ability to effectively communicate thoughts, feelings, and identity to others is an important aspect of occupational performance. The symptoms of Parkinson's disease can impair a person's ability to verbally and non-verbally communicate with others. In order to better understand issues of communication functioning for this population, research tools to describe expressive and communicative behavior during occupation and social interaction are needed. In this study, six persons with Parkinson's disease participated in individual, videotaped interviews focused on problem solving during daily activities. Three trained graduate students viewed edited clips from the videotapes and completed a rating scale of expressive behavior designed by the authors. Data support the reliability and construct validity of the behavioral rating scale, suggesting that measures of expressive behavior of persons with Parkinson's disease can be effectively derived using short segments of videotaped activity.