'When I conducted a systematic review of existing research, classroom based instruction on vocabulary where speech pathologists were working with regular teachers, yielded very successful results,' he said.

'Using simple demonstrations, picture cues or graphic organisers, summarisation techniques, allowing multiple opportunities to respond and repeat, and asking questions at various levels of complexity, are techniques that have proven to be most effective in improving language skills,' he said.

'Most importantly, if you are doing this on an intense daily schedule with the help of a speech pathologist in a classroom setting, you will see a great improvement in the child's literacy skills,' Gillam added.

He said children with language impairment were at risk of social and academic problems and, later in life, vocational problems.