Longitudinal Analysis of Developmental Trajectories in Children With Language Delay

We examined developmental trajectories of receptive and expressive language abilities in children aged 1 to 5 years and beyond. We retrospectively recruited 158 children. Using the Sequenced Language Scale for Infants and the Preschool Receptive-Expressive Language Scale, children were grouped as typically developing (TD), mildly delayed (MD), or severely delayed (SD). Language was assessed under 3 age groups: under 2 years, 2 to <5 years (in 6-month intervals), and ≥5 years. Most TD children before age 5 remained TD, although some transitioned to MD or SD, especially after 3.5 years. The MD children at younger ages often improved to TD, but this likelihood declined approaching age 5. Those classified as SD had a lower chance of improvement, with fewer transitioning to MD or TD. The likelihood of improvement from MD and SD decreased with age. Children exhibiting both MD and SD demonstrate potential for improvement; however, the likelihood decreases with age.