The Wechsler Adult Intelligence Scale-Fourth Edition, Greek Adaptation (WAIS-IV GR): confirmatory factor analysis and specific reference group normative data for Greek Australian older adults

Abstract

ABSTRACT Objectives In the absence of reliable and valid neuropsychological measures, accurate assessment of culturally diverse groups is a challenge facing the Australian neuropsychological community. This study aimed to investigate the construct validity and to develop specific reference group norms using the WAIS-IV Greek adaption (WAIS-IV GR) for Greek Australian older adults. Method A convenience sample of 90 healthy older Greek Australians (M = 77.14 ± 4.46; range = 70–85; 39 males & 51 females), with a primary school level of education (M = 5.60 ± 0.68; Range = 4–6) were recruited throughout the Melbourne metropolitan area. Results Regression modelling showed that age was the most significant predictor, therefore, subtest normative data were stratified according to three age bands. Normative data for all WAIS-IV GR subtests and indices were calculated, in addition to values for the 90% and 95% confidence levels. Confirmatory factor analysis indicated that a four-factor solution consisting of the WAIS-IV GR Index Scores displayed a superior fit with significant parameters of acceptable magnitude. Conclusion Findings support the application of the traditional WAIS-IV factor structure to a Greek Australian sample. Utilising specific reference group norms for Greek Australians with limited education will facilitate and improve access of cognitive assessment within this population. KEY POINTS What is already known on this topic:(1) The use of existing norms can lead to underestimating cognitive function in culturally diverse groups. (2) Access to culturally appropriate norms and tests for the assessment of culturally diverse groups in Australia is limited. (3) Neuropsychological test results are influenced by age, education, and culture. What this topic adds:(1) This is the first study to validate and provide WAIS-IV norms for a culturally diverse group in Australia. (2) Confirmatory factor analysis indicated that the internationally recognised WAIS-IV factor structure was appropriate for Greek Australian older adults. (3) Development of these resources will facilitate and improve access of cognitive assessment within this population.