Subjective clinical ratings comprise the outcome measures by which treatments for psychiatric disorders demonstrate efficacy and gain regulatory approval. The problem of inter-rater reliability inherent to these instruments presents a significant challenge for drug development. Poor inter-rater reliability has been reported repeatedly for scales measuring symptom severity, and starkly demonstrated for diagnosis by the recent DSM field trials (e.g. For Major Depression kappa = 0.28).
Tandem ratings is a simple technique which aims to minimize the impact of subjectivity in clinical ratings. Max Hamilton proposed using two raters as a means of improving reliability in 1960. Unfortunately, few clinical trials have utilized this approach. Most RCTs rely on standardized programs of rater training and certification to produce acceptable inter-rater reliability, rather than accept the costs and operational burdens of using two raters.
These problems are largely overcome by the use of an approach to tandem ratings in which one of the raters is a site based rater, while the other is a computer that simulates interactive rater administered interviews to collect subject responses and employs scoring algorithms to produce severity scores or estimate the likelihood of diagnosis. Utilizing computer assessments that by design generate measures near the middle of the distribution of typical site-based raters, allows studies to focus on subjects with tandem ratings indicating high diagnostic confidence and severity scores within tolerance limits set by study sponsors.
Dr. Gary Sachs, Therapeutic Area Leader at Bracket, will be discussing Bracket’s implementation of this approach and will review evidence showing the impact of tandem ratings on signal detection in recent global clinical trials at the Translational CNS Summit 2014.
The Summit is being held April 29th – 30th in Boston and will bring together leaders in CNS research and development who share the common goal of developing effective therapies for those in need. Successful technologies and techniques will be discussed, enabling industry experts to collaborate with their peers in an effort to advance the industry.
For more information on the Translational CNS Summit 2014, click here.