Norms for healthy adults aged 18-87 years for the Cognitive Drug Research System: An automated set of tests of attention, information processing and memory for use in clinical trials

The Cognitive Drug Research (CDR) System is a set of nine computerized tests of attention, information processing, working memory, executive control and episodic memory which was designed for repeated assessments in research projects. The CDR System has been used extensively in clinical trials involving healthy volunteers for over 30 years, and a database of 7751 individuals aged 18–87 years has been accumulated for pre-treatment data from these studies. This database has been analysed, and the relationships between the various scores with factors, including age, gender and years of full-time education, have been identified. These analyses are reported in this paper, along with tables of norms for the various key measures from the core tasks stratified by age and gender. These norms can be used for a variety of purposes, including the determination of eligibility for participation in clinical trials and the everyday relevance of research findings from the system. In addition, these norms provide valuable information on gender differences and the effects of normal ageing on major aspects of human cognitive function.