Comparisons of steps in theory-of-mind development between autistic and typically developing children in Hong Kong and mainland China

Background: While a meta-analysis has shown that false belief (FB) understanding of typically developing (TD) children in Hong Kong (HK) develops much later than that of children in mainland China (Liu et al., 2008), whether the former also acquire other theory-of-mind (ToM) skills later than the latter remains unclear. Moreover, no study has compared ToM skills of HK autistic children with those of mainland Chinese autistic children. Wellman and Liu (2004) have devised a ToM scale to investigate the developmental sequence of five ToM skills: diverse desires (DD), knowledge access (KA), diverse beliefs (DB), contents FB (CFB), and hidden emotion (HE). Given Liu et al.’s finding, we hypothesize that both autistic and TD children in HK will perform worse than their mainland China counterparts in CFB. Furthermore, given Zhang et al.’s (2016) finding that the developmental sequence of the five ToM skills in mainland Chinese autistic children deviated from that in TD children, we hypothesize that the same will be observed in HK autistic and TD children. Objectives: To examine HK autistic and TD children’s performance on Wellman and Liu’s (2004) ToM scale, and to compare the results with those from mainland Chinese autistic and TD children reported by Zhang et al. Methods: 47 ASD (M = 6.16; range: 3.5–9.58) and 93 TD children in HK (M = 5.10; range: 3.33–6.83) participated. They were matched with Zhang et al.’s autistic and TD groups on age. To compare the developmental sequence of ToM between HK autistic and TD children, another TD group (N = 137; M = 5.61) matched with ASD group on language ability was formed. The tasks used by Zhang et al. (translated into Cantonese) assessed understanding of the five ToM skills. Results: Among the five ToM tasks, chi-square analyses showed that HK TD children’s passing rates were significantly lower than mainland Chinese TD children on KA and HE (see Table 1). In contrast, HK autistic children significantly outperformed mainland Chinese autistic children on KA, DB, and CFB (see Table 1). Like Zhang et al., we found that HK autistic children’s developmental sequence of the five ToM skills (i.e., KA < DD < DB < CFB < HE) deviated from that of HK TD children (i.e., DD < KA < DB < CFB < HE) (see Table 2). Moreover, the developmental sequence of the five ToM skills in HK autistic children differed from that of mainland Chinese autistic children, which was DD < DB < KA < CFB < HE (see Table 2). Conclusions: This study partially confirmed our hypothesis: the developmental sequence of the five ToM skills in HK autistic children deviated from that of HK TD children. However, contrary to our hypothesis, neither TD nor autistic children in HK performed worse than their mainland Chinese counterparts on CFB. Our finding that the developmental sequence of the five ToM skills in HK autistic children differed from that of mainland Chinese autistic children supports the idea that the developmental sequence of ToM is subject to cross-cultural/regional variations.