Preschoolers' mastery of advanced counting: The best predictor of addition skills 2 years later

The current study addressed the following question: Among preschoolers' basic numerical abilities, what are the best predictors for the later addition skills? We measured numerical abilities at preschool age and used dominance analysis to determine the dominant predictor for addition skills 2 years later. We tested seven numerical specific predictors (counting, advanced counting, enumeration, Give-N, collection comparison, number-word comparison, and approximate addition). Both quantitative and qualitative aspects (accuracy, strategy choice, and fluency) of addition skills were measured. The results show that the predictor weights for addition skills were 39% (counting), 37% (advanced counting), and 25% (collection comparison). We concluded that counting ability and especially advanced counting measured in early preschool is the most robust predictor of addition skills 2 years later (even after controlling for global cognitive abilities). This study generalized the previous findings found for Western children to Vietnamese preschoolers (N = 157, M_age = 4.8 years); extended and highlighted the role of advanced counting (count from a number other than 1) to later addition performance, mature strategy, and calculation fluency; and suggested further implications.