Psychometric properties of the adaptation of the informant questionnaire on cognitive decline in the elderly (iqcode) in the survey of health, aging and retirement in europe (share)

The growth of dementia cases over the years has promoted methods for efficient early diagnoses such as the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Recently, the Survey of Health, Aging and Retirement in Europe (SHARE) made an adaptation of the IQCODE. In this work, we will examine the psychometric properties of this adaptation of the IQCODE. The sample was composed by 1,059 participants. SHARE's adaptation of the scale contained seven items, used two years for changes in mental abilities, and employed a 3-point response scale. We explored confirmatory factor analysis (CFA), coefficient omega estimation and self-report of Alzheimer's diagnoses as criterion. The one-factor structure was supported:.2(14) = 218.92, p <.001; CFI =.995; SRMR =.028. There was evidence of internal consistency and criterion related validity, and ROC curve indicated acceptable discrimination. SHARE's adaptation of the IQCODE can be used as an appropriate tool for cognitive impairment screening within a large-scale survey framework.