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Full-Length Research Report

Validity and Reliability of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE)

Preliminary Findings Among the Older Population of Iran

Published Online:August 22, 2019https://doi.org/10.1024/1662-9647/a000209

Abstract

Abstract. This study examines the psychometric properties of the IQCODE and its applicability in the Iranian elderly population. A group of 95 elderly patients with at least 4 years of formal education who fulfilled the criteria of DSM-IV-TR for dementia were examined by the MMSE and the AMTs. The Farsi version of the IQCODE was subsequently administered to their primary caregivers. Results showed a significant correlation (p = .01) between the score of the questionnaire and the results of the MMSE (r = −0.647) and AMTs (r = −0.641). A high internal reliability of the questionnaire was confirmed by Cronbach’s alpha coefficient (α = 0.927) and test-retest reliability by correlation coefficient (r = 0.81). This study found that the IQCODE has acceptable psychometric properties and can be used for evaluating the cognitive state in the elderly population of Iran.

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