INFORMANT RATINGS OF COGNITIVE DECLINE OF ELDERLY PEOPLE - RELATIONSHIP TO LONGITUDINAL CHANGE ON COGNITIVE TESTS

Formal assessment of cognitive decline with cognitive tests can be dif ficult, requiring either two measurement points or a comparison of 'ho ld' with 'don't hold' tests. Informant-based assessment provides an al ternative approach because informants can adopt a longitudinal perspec tive and directly rate cognitive change. A study was carried out to as sess the validity of informant ratings collected by means of the Infor mant Questionnaire on Cognitive Decline in the Elderly (IQCODE). A com munity sample of 500 subjects aged 74 or over underwent four cognitive tests on two occasions 31/2 years apart. On the second occasion, info rmants filled out the IQCODE. Subjects rated as having moderate or sev ere decline were found to have greater change on the cognitive tests. These findings support the validity of informant ratings of cognitive decline.