During production of the above-mentioned article an error was introduced to the abstract. Cambridge University Press apologise for this error.
Original
Approximately 2013 % of children and adolescents were using DS; the highest use was among children aged 1–3 years old, and the lowest use was among adolescents aged 16–18 years
Correction
Approximately 20.3 % of children and adolescents were using DS; the highest use was among children aged 1–3 years old, and the lowest use was among adolescents aged 16–18 years