The University of Manchester Age and Cognitive Performance Research Centre (ACPRC) programme began in 1983 and this study has documented longitudinal trajectories in cognitive function in a large sample of older adults in the North of England, UK17. Recruitment took place in Newcastle and Greater Manchester between 1983 and 1992. At the outset of the study, 6063 volunteers were available, (1825 men, 4238 women), with a median age of 65 years (range 44 to 93 years). Over the period 1983 to 2003, two alternating batteries of cognitive tasks applied biennially were designed to measure fluid and crystallized aspects of intelligence. These included: the Alice Heim 4 (AH4) parts 1 and 2 tests of general intelligence; Mill Hill Vocabulary A and B vocabulary tests; the Cattell and Cattell Culture Fair intelligence tests; and the Wechsler Adult Intelligence Scale Vocabulary test. Detailed task descriptions were provided previously17. Following informed consent, venesected whole blood was collected for DNA extraction. Ethical approval for all projects was obtained from the University of Manchester.
