Clinical assessment of Persian-speaking children with language impairment in Iran :exploring the potential of language sample measures

Abstract

Access to evidence-based assessment for diagnosing children with primary language impairment (PLI) in Iran is limited. This study aimed to explore diagnostic criteria employed by Iranian speech therapists for defining PLI and examine the diagnostic potential of language sample measures (LSMs) for Persian-speaking children. Thirty nine speech and language therapists (SLTs) contributed in a qualitative-quantitative study to explore the criteria currently used by Iranian SLTs to assess and diagnose Persian-speaking children with PLI. Personally-defined diagnostic procedures, based on the results of the questionnaires and focus groups were summarised to obtain a general picture of decision-making methods in identifying Iranian children with PLI. The International Classification of Functioning, Disability and Health (ICF) was used as an organising framework for establishing a consensus as to what constitutes a language impairment, since no commonly accepted reference standard currently exists in Iranian clinical practice. The assessment potential of LSMs in Persian was examined using the framework of diagnostic research and included a pre-accuracy study followed by phase I and II studies. Twenty seven pre-school children with typically-developing language (TDL) and 24 age-matched children with PLI, aged 42 to 54 months, were recruited. Language samples were recorded as each mother played with her child. None of correlations between age and the LSMs were statistically significant in either group of children (pre-accuracy phase). However, a majority of the LSMs could differentiate children at the group level (phase I). Five measures: Grammaticality/Ungrammaticality, Ungrammatical Utterances, MLUw-excluding one-word utterances, and Semantic Errors, provided good diagnostic accuracy when examined at the level of the individual child (phase II). An ICF-based reference standard for defining PLI in Iranian Pre-school children has been developed to enhance the consensus among Iranian SLTs. It was applied to recruit the children to the DA study, resulting in five LSMs which are clinically able to differentiate between children with and without PLI.