Efficacy of the Treatment of Developmental Language Disorder: A Systematic Review

Abstract

Background. Language disorder is the most frequent developmental disorder in childhood and it has a significant negative impact on children’s development. The goal of the present review was to systematically analyze the effectiveness of interventions in children with developmental language disorder (DLD) from an evidence-based perspective. Methods. We considered systematic reviews, meta-analyses of randomized controlled trials (RCTs), control group cohort studies on any type of intervention aimed at improving children’s skills in the phono-articulatory, phonological, semantic-lexical, and morpho-syntactic fields in preschool and primary school children (up to eight years of age) that were diagnosed with DLD. We identified 27 full-length studies, 26 RCT and one review. Results. Early intensive intervention in three- and four-year-old children has a positive effect on phonological expressive and receptive skills and acquisitions are maintained in the medium term. Less evidence is available on the treatment of expressive vocabulary (and no evidence on receptive vocabulary). Intervention on morphological and syntactic skills has effective results on expressive (but not receptive) skills; however, a number of inconsistent results have also been reported. Only one study reports a positive effect of treatment on inferential narrative skills. Limited evidence is also available on the treatment of meta-phonological skills. More studies investigated the effectiveness of interventions on general language skills, which now appears as a promising area of investigation, even though results are not all consistent. Conclusions. The effectiveness of interventions over expressive and receptive phonological skills, morpho-syntactic skills, as well as inferential skills in narrative context underscores the importance that these trainings be implemented in children with DLD.

Developmental Language Disorder: Early Predictors, Age for the Diagnosis, and Diagnostic Tools. A Scoping Review

“…We performed a systematic search of studies as part of a Consensus Conference about diagnosis and treatment of children with language disorders, held in Italy in November 2018 and published in November 2019 [ 32 ]; we further updated the search until December 2020. This Consensus Conference agreed to use the diagnostic label Disturbo Primario del Linguaggio (i.e., Primary Language Disorder) for the Italian context [ 32 , 33 ]. For the Italian clinical system, this label refers to a developmental language disorder that is not acquired or associated with a known biomedical cause.…”

“…Similar to DLD [ 22 ], its diagnosis is not precluded by the presence of neurobiological or environmental risk factors or co-occurrence with other neurodevelopmental disorders and does not require a mismatch between verbal and nonverbal ability. Therefore, the notion of Primary Language Disorder, as used in this Consensus Conference [ 32 , 33 ], corresponds to that of the term DLD, recently adopted in the literature [ 22 ], already illustrated in the Introduction and used throughout the present review. This Consensus Conference followed the steps detailed in the Methodological Manual of the Italian Superior Institute of Health [ 59 ].…”

“…Nonetheless, it has to be considered that poor efficacy seems to depend on the difficulty to significantly influence and modify the developmental trajectories of children at risk for DLD through intervention, rather than to the poor capacity of the tools to identify children at risk (sensitivity and specificity features of several tests have proved to be good). This consideration should therefore encourage research on effective intervention practices in particular [ 33 ], and suggests that a good association between the use of reliable screening tools and targeted interventions could be the desired solution.…”

“…Crucially, it is now widely accepted that these linguistic difficulties may co-occur with a variety of other cognitive weaknesses, such as in procedural memory [ 23 ], motor control [ 24 ], phonological working memory [ 25 ], and executive functions [ 26 , 27 ], with growing evidence about the impact of such difficulties on linguistic performance (e.g., [ 28 ]). Although terms such as ‘Primary Language Impairment’ and ‘Primary Language Disorder’ have also been used in the literature to account for the aspecificity of this language disorder and its unknown origin [ 29 , 30 , 31 , 32 , 33 ] (for further details, see the Methods section), we will use the term DLD, according to the more recent international consensus [ 22 ], regardless of how this disorder was labelled in the papers reported in this review.…”

Implicit Representation of Grammatical Gender in Italian Children with Developmental Language Disorder: An Exploratory Study on Phonological and/or Syntactic Sensitivity

“…Therefore, it was recommended to use more measures to increase diagnostic accuracy. It also emerged the importance of early assessment, from 3 years onward (see also Rinaldi et al, 2021).…”