Cross-border marriage and disparities in early childhood development in a population-based birth cohort study: The mediation of the home environment

Background Taiwan has experienced a large influx of cross-border marriage migrants in recent years. The majority have been women in their childbearing ages and have come from countries with lower average standards of living than Taiwan. This trend has changed the ethnic composition of children who live in Taiwan, and it has generated considerable social concern over the future health status of Taiwan's citizens. This study aimed to examine: (1) whether there are disparities in development between children reared in families characterized by cross-border marriages and children reared in families with two Taiwanese-born parents; and (2) whether the quality of home environment explains the group differences in early childhood development. Methods Data came from the Taiwan Birth Cohort Study. A total of 19499 participants who completed 6-month, 18-month and 3-year surveys were included for analysis. Cross-border marriage status was defined by mother's original nationality and categorized into three broad groups: Taiwanese-born, Chinese cross-border and South-East Asian (SEA) cross-border. Early childhood development was measured at age 3 years, and covered the domains of gross motor, fine motor, language and socio-emotional competence. Hierarchical linear regressions were used to examine the mediation effects of the home environment. Results Children of Chinese and SEA cross-border groups scored lower in fine motor, language and socio-emotional competence than those of their Taiwanese-born counterpart at age 3 years. Chinese-Taiwanese group differences in all three developmental domains became insignificant after the addition of home environment, while SEA-Taiwanese group differences in fine motor and language development remained, yet were noticeably reduced. The mediation of home environment was further confirmed using the Sobel test. Conclusions Home environment plays a central role in reducing the disparities in developmental outcomes among children of different marriage groups. Interventions should be directed towards enhancing the quality of early home environment for children reared in families of cross-border marriages.