A prospective longitudinal study of shyness from infancy to adolescence: stability, age-related changes, and prediction of socio-emotional functioning.

This longitudinal, population-based and prospective study investigated the stability, age-related changes, and socio-emotional outcomes of shyness from infancy to early adolescence. A sample of 921 children was followed from ages 1.5 to 12.5 years. Parent-reported shyness was assessed at five time points and maternal- and self-reported social skills and symptoms of anxiety and depression were assessed at age 12.5 years. Piecewise latent growth curve analysis was applied, with outcomes regressed on latent shyness intercept and slope factors. Results showed moderate stability and increasing levels of shyness across time, with more variance and a steeper increase in early as compared to mid-to-late childhood. Both stable shyness and increased shyness in mid-to-late (but not early) childhood predicted poorer social skills and higher levels of anxiety and depression symptoms in early adolescence. The implications of the evidence for two developmental periods in shyness trajectories with differential impact on later socio-emotional functioning are discussed.