Similarities and Differences in the WAIS-IV Performances in Korean and U.S. Populations

Objective: This exploratory study examines the cognitive profiles of South Koreans using the WAIS-IV. It compares scores from the original U.S. version (USW) with those from the Korean version (KW) to identify potential cultural influences on performance.

Method: Raw scores corresponding to a scaled score of 10 for each subtest of the KW were used to compare the performances of South Koreans and Americans across subtests and composite indices. The impact of education was assessed through correlations with educational attainment ratios from both countries.

Results: When combined across all age groups, the scores of the South Korean sample were significantly lower than those of U.S. sample on the Similarities, Comprehension, and Picture Completion subtests, and Verbal Comprehension Index. However, younger South Koreans scored significantly higher on Block Design, Matrix Reasoning, Visual Puzzles, Figure Weights, Digit Span, Arithmetic, Letter-Number Sequencing, Symbol Search, and Coding and all composite scores except Verbal Comprehension. Older South Koreans scored significantly lower on Similarities, Vocabulary, Comprehension, Matrix Reasoning, Visual Puzzles, Picture Completion, and the composite scores of Verbal Comprehension and Perceptual Reasoning, compared to their U.S. counterparts. All subtest and composite scores were highly correlated with education.

Conclusions: The South Korean and U.S. samples demonstrated distinct cognitive profiles on the WAIS-IV when comparing relative performances on subtests and composite measures. Cultural factors including socioeconomic changes, education quality, nuances in language characteristics, and implicit differences in cognitive processing were discussed as possible contributors to the unique cognitive profile of the South Korean sample.