A Validation Study of Korean-Version Autism-Spectrum Quotient (K-AQ)

Background: Autism is a developmental disorder characterized by difficulties in social interaction and communication, and by restricted and repetitive behaviors (DSM-5,2013). There are some diagnostic instruments for autism, such as the ADI-R, the ADOS-2, that are time-consuming to manage. People who are at risk or diagnosed with autism have been increased in Korea; however, there is no brief self-administered and time-saving scale for measuring the degree to which any individual adult with normal IQ may have the 'autistic traits' or ‘the broader phenotype’(Bailey et al.,1995).

Objectives: This study is aimed to test the validation of a Korean-version AQ with Korean HFASD, general adults and university students.

Methods: Totally 957 volunteers participated and were divided into three groups. Group1 comprised 20 males who had been diagnosed with HFASD and their mean age was 22.4 (SD:3.69). Group2 comprised 200 adults selected at random (Male:68, Female:132) from general adults whose mean age was 37.5 (SD:10.57). Group3 was made up of 737 students (Male:336, Female:401) who are attending university in Korea and the mean age was 21.4 (SD: 2.63). The procedure was exactly replicated as the UK (Baron-Cohen et al., 2001) and Japanese (Wakabayashi et al., 2006) studies.

Results: The cut-off score was determined as an AQ score of 31+, based on the results that 80% of HFASD group scored at this level, while only 2.4% of controls did so. The mean AQ scores of three groups were compared using independent t-test. In the results of comparing HFASD group and General group, the HFASD group showed its mean as 26.85(SD:5.91) and the General group presented its score as 18.01(SD:6.57). There was a significant difference between two groups (p<.001). In the comparison between HFASD and Student group, Student group displayed its mean as 18.94 (SD:5.92), and there was a significant difference between two groups (p<.001).

In the subscale results, the HFASD group showed higher scores than both General and Student groups in all subscales. The HFASD group showed their lowest score in Imagination and highest score in Attention switching. Comparing the HFASD and General group, there was a significant difference in all subscales; Communication (p<.001), Social skills (p<.01), Imagination (p<.001), Local details (p<.01), and Attention switching (p<.05). In the result between the HFASD and Student groups, there was a significant group difference in four subscales; Communication (p<.001), Social skills (p=.001), Imagination (p<.001), and Local details (p<.05). In addition, males showed the higher mean score in General group, while females in Student group demonstrated higher mean AQ. There was a significant gender difference within some subscales in both General and Student groups.

Conclusions: This study investigated the validation of Korean-version AQ in adults with HFASD, control, and students. These results emphasize the significant group differences in mean AQ and scores of subscales between HFASD and control groups (both general and student groups). It suggests that the Korean-version AQ can be used to validate the autistic traits in individuals with HFASD from controls, although the limited numbers of participants with HFASD were involved in this study.