Validity of brief intelligence tests for patients with Alzheimer's disease

The validity of two kinds of brief intelligence tests for patients with Alzheimer's disease (AD) was investigated. In study 1, five short forms of the Japanese Wechsler Adult Intelligence Scale-Revised (JWAIS-R) were administered to 102 AD patients. The results showed that the intra-class correlation coefficients (ICC) between IQ estimated with the short forms and those obtained by administration of the full JWAIS-R were satisfactory, ranging from 0.82 to 0.98, and that the abbreviated forms took a shorter time to execute. In study 2, the Raven's Coloured Progressive Matrices (RCPM) and the Mini-Mental State Examination (MMSE) were administered to 67 AD patients. The ICC between the IQ estimated with these tests and the full-scale IQ of the JWAIS-R were both acceptable at 0.57, and each test could be carried out in a very short time. It was concluded that these brief tests, particularly the WAIS-R short forms, are highly practical for quick measurement of intelligence in AD patients, although they have their respective limitations.