Clinical validity of the Japanese version of WAIS-III short forms: Adaptation for patients with mild neurocognitive disorder and dementia.

We investigated the Japanese WAIS-III short form utility in mild neurocognitive disorder and dementia. Our sample consisted of 108 old patients (ages: 65-89; mean age = 78.3). Fifteen short forms (SFs) and full-scale (FS) IQs were compared. The SFs included Dyads (SF1, SF2), Triads (SF3), Tetrads (SF4, SF5, SF6, SF7), Pentad (SF8), Six-subtest (SF9), Seven-subtests (SF10(a)(b), SF11(a)(b), SF12), and Nine-subtest (SF13). Correlations between SFIQs and FSIQ were all significant. Significant differences also were found in paired t-test between FSIQ and 5 SFIQs (SF2: t = -4.16, SF5: t = -7.06, SF7; t = 2.59, SF10(a): t = 2.56, SF12: t = -4.82; p < .05). On the point of clinical accuracy, two SFs led to an appropriate estimated IQ (SF11(a): 84.3%, SF13: 91.7%; within 95% confidence interval and 2 standard error of measurements of FSIQ). However, SF13 was considered to still have a long administration time. The present results suggest that SF11(a) could be the most useful to estimate IQ for Japanese speaking patients with mild neurocognitive disorder and dementia. SF11(a) consists of seven subtests of Similarities, Arithmetic, Digit Span, Information, Picture Completion, Digit Symbol-Coding, and Matrix Reasoning (Ryan & Ward, 1999), and the formula (Axelrod et al., 2001) should be adopted to convert scaled scores into estimated IQ scores.