This study extended the internal/external frame of reference (I/E) model to referencing longitudinal data for children from different backgrounds. The extended I/E model was different from the traditional I/E model because early-year verbal and mathematical cognitive abilities offered fewer opportunities for external comparison in school than did later-year school achievement. The extended I/E model was investigated by structural equation modelling using data from the Millennium Cohort Study. The total sample size was 8,731 English children, among whom 1,417 were ethnic minority, 3,327 were disadvantaged and 3,987 were advantaged children. The results revealed that the traditional I/E model prediction was supported only for age 7 cognitive abilities. The results based on age 3 or age 5 cognitive abilities are only consistent with the traditional I/E model prediction in the paths predicting mathematical self-concept. The extended I/E model was typically supported for advantaged, disadvantaged and ethnic minority children, in descending order.
International Journal of Quantitative Research in Education