Contributions of early motor deficits in predicting language outcomes among preschoolers with developmental language disorder.

Only 15 children with DLD and 14 children with TD were analysed, down from 40 children with DLD and 21 children with TD at Year 1, so the findings are based on a small sample. Some children did not have all predictor scores: 12 of 15 children with DLD and all 14 children with TD had standardised predictor scores, while 14 of 15 children with DLD and 11 of 14 children with TD had speech-motor variability data. The study was observational, so motor scores are linked to later language outcome but do not show that motor deficits cause persistent language disorder or that motor treatment would improve language. Many children with DLD had received speech-language therapy before, and information about outside therapy frequency, duration, and focus was limited, so treatment history could influence outcomes. The experimental speech-motor task was a simple repeated sentence; the more complex sentence generation task could not be completed by most children with DLD at Year 1, so the null speech-motor finding may reflect task simplicity rather than absence of a speech-motor effect. The unexpected negative relationship between Year 1 consonant inventory and Year 3 language in the DLD model was not explained and could reflect sample size, test limitations, or diagnostic overlap. The Movement Assessment Battery for Children was used as a motor ability measure, not to diagnose developmental coordination disorder, so the motor findings do not identify developmental coordination disorder.

No conflicts of interest were declared. The article is listed as supported by NIH extramural research.

Do not read the motor finding as proof that motor problems cause persistent language disorder or that motor therapy will improve language. This was a small observational study, and the motor measure only added prediction beyond language and speech measures in children with DLD.