Special Series on the Wechsler Adult Intelligence Scale-IV Performances in Five Asian Countries: Summary of Findings, Clinical Implications, and Future Directions.

Introduction: This special series of exploratory studies compared WAIS-IV performances in five Asian countries: Japan, South Korea, Taiwan, India, and Indonesia with the U.S. The studies examined cognitive profiles across age groups to develop hypotheses on how culture can impact cognition. This summary article integrates the findings from each study to determine similarities and differences across Asian countries and proposes possible underlying cultural factors impacting cognition.

Methods: In each study, raw scores corresponding to a subscale score of 10 were scored with U.S. norms across all age groups. Index scores were calculated with the adjusted scale scores. The impact of education on test performances was determined by correlating WAIS-IV scores with a ratio of educational attainment for each country with the U.S. for each age group. Findings from each country were then integrated to develop hypotheses on cultural factors that impacted cognitive profiles.

Results: East Asian countries (Japan, South Korea, Taiwan) demonstrated weaker Verbal Comprehension Index scores and stronger Processing Speed Index scores than the U.S. sample, although the latter was moderated by age. East Asian countries demonstrated stronger performances on Perceptual Reasoning versus Verbal Comprehension tests. East Asians and the Java subset of the Indonesian sample demonstrated a pattern of stronger performances in younger versus older cohorts which was significantly correlated with educational attainment.

Discussion: Cultural factors impacting cognition were proposed. Clinical implications of the findings were discussed and directions for future studies to examine the relationship between culture and cognition were recommended.