Grammatical number inflection in Arabic-speaking children and young adults with Down syndrome.

The study used a non-standard picture naming task because no validated and standardised tool exists for Jordanian Arabic speakers with Down syndrome. All participants came from the Nazik Al Hariri Welfare Centre in Amman and had trisomy 21, no hearing or vision problems and no additional medical or behavioural conditions, so results may not apply to people with Down syndrome who have those conditions. The study compared different people at three ages rather than following the same people over time, so it cannot show how an individual's grammatical number changes with age. There was no typically developing control group in the study, so the percentages describe the Down syndrome groups only. Free speech and conversations were recorded but not analysed statistically, so the results depend on elicited picture naming. Correct forms were identified by the researchers and one language therapist, and pronunciation disagreements were excluded, which may affect scoring.

No funding or conflict of interest declaration is reported in the supplied text. Ethical clearance was obtained from the Scientific Research and Research Ethical Approval Committee of the Hashemite University, and permission was granted by the Department of English Language & Literature.

Do not conclude that language training improves grammatical number from this paper. The study observed performance across age groups and did not deliver or test any therapy.