We first replicated the data analytic strategy used in Duncan et al. (2007) with a population-based data set of French-speaking children from Quebec (Canada). Prospective associations were examined between cognitive, attention, and socioemotional characteristics underlying kindergarten school readiness and second grade math, reading, and general achievement. We then extended this school readiness model by including motor skills as an additional element in the prediction equation and expanded the original strategy by including classroom engagement. The Montreal Longitudinal-Experimental Preschool Study, featured in Duncan et al., served as the Canadian reference group. In the replication model, kindergarten cognitive and attention characteristics predicted achievement by the end of 2nd grade. Although inconsistent across outcomes, behavioral problems and skills also emerged as predictors of some aspects of later achievement. Coefficients for kindergarten math skills were largest, followed by attention skills, receptive language skills, attention problems, and behavior. Most coefficients resembled those generated in the initial study. In our extension model, fine motor skills added their significant contribution to the prediction of later achievement above and beyond the original key elements of school readiness. Our extension model confirmed prospectively associations between kindergarten cognitive, attention, fine motor, and physical aggression characteristics and later achievement and classroom engagement by the end of 2nd grade. Although they comparatively showed better long-term benefits from stronger early attention skills, girls with less kindergarten cognitive skills were more vulnerable than boys with similar deficits when predicting 2nd grade math.

Objective To estimate the influence of early childhood television exposure on fourth-grade academic, psychosocial, and lifestyle characteristics. Design Prospective longitudinal study. Setting Institut de la Statistique du Québec, Québec, Canada. Participants A total of 1314 (of 2120) children. Main Exposure Parent-reported data on weekly hours of television exposure at 29 and 53 months of age. We conducted a series of ordinary least-squares regressions in which children's academic, psychosocial, and lifestyle characteristics are linearly regressed on early and preschool television exposure. Outcome Measures Parent and teacher reports of academic, psychosocial, and health behaviors and body mass index measurements (calculated as weight in kilograms divided by height in meters squared) at 10 years of age. Results Adjusting for preexisting individual and family factors, every additional hour of television exposure at 29 months corresponded to 7% and 6% unit decreases in classroom engagement (95% confidence interval [CI], −0.02 to −0.004) and math achievement (95% CI, −0.03 to 0.01), respectively; 10% unit increases in victimization by classmates (95% CI, 0.01 to 0.05); 13% unit decreases in time spent doing weekend physical activity (95% CI, 0.81 to 2.25); 9% unit decreases in activities involving physical effort (95% CI, −0.04 to 0.00); higher consumption scores for soft drinks and snacks by 9% and 10% (95% CI, 0.00 to 0.04 and 95% CI, 0.00 to 0.02), respectively; and 5% unit increases in body mass index (95% CI, 0.01 to 0.05). Preschool increments in exposure also made a unique contribution to developmental risk. Conclusions The long-term risks associated with higher levels of early exposure may chart developmental pathways toward unhealthy dispositions in adolescence. A population-level understanding of such risks remains essential for promoting child development.