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Abstract
Objective Developmental language disorder (DLD) is a common communication disorder that impacts children’s ability to learn, comprehend and use language effectively, yet it remains under-researched, particularly in the Arab countries. This scoping review aims to provide a comprehensive narrative summary on the epidemiology of DLD among children aged ≤10 years in the Arab countries.
Design A scoping review.
Data sources PubMed, Scopus and Web of Science.
Eligibility criteria We included studies that reported on the prevalence or risk factors of DLD in children aged ≤10 years from any Arab country. Only peer-reviewed publications were considered, and the study populations were required to consist of children without underlying medical conditions known to contribute to language or speech delay.
Data extraction and synthesis Two reviewers independently performed abstract and full-text screening and extracted relevant data. The risk factors identified as linked to DLD were grouped into maternal and perinatal factors, factors related to children and family and environmental factors.
Results From 4832 citations, 17 were deemed eligible and included in this review. The reviewed studies were conducted in only seven Arab countries, with the majority from Egypt (eight studies, 47.1%) and Saudi Arabia (four studies, 23.5%). The reported prevalence of DLD ranged from 3.2% in Egyptian children aged 3–6 years to 25.6% in Saudi Arabian children aged 1–5 years. Among the identified risk factors for DLD were sex, low birth weight, a history of speech and language delay in the family, parental socioeconomic status, perinatal complications, larger family size and early screen exposure.
Conclusion The reported prevalence of DLD varied across the seven Arab countries. Strategies to address the preventable underlying DLD-associated risk factors are required. There is a clear gap in evidence related to the burden of DLD among children in most of the 22 Arab countries, which warrants further research.
- Child
- Community child health
- Primary Prevention
- PUBLIC HEALTH
- Risk Factors
Data availability statement
Data sharing not applicable as no datasets generated and/or analysed for this study.
This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.
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STRENGTHS AND LIMITATIONS OF THIS STUDY
This study closely adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines, and the chance of human error was minimised by two independent reviewers who performed screening and data extraction.
Owing to the scarcity of studies conducted in the Arab countries, multiple studies identified through reference lists were included in our study despite the lack of sound methodology.
We were unable to subcategorise developmental language disorder into speech, expressive language or receptive language delays because of a lack of available data and unclear terminology in the reviewed studies.
Introduction
Developmental language disorder (DLD) in children is defined as a condition characterised by persistent and substantial difficulties with language that affect communication abilities. These difficulties cannot be attributed to medical conditions, such as congenital cleft palate, autism spectrum disorder, cerebral palsy, hearing loss acquired after spoken language is established, intellectual disability or selective mutism.1 In previous years, considerable inconsistency existed in the terminology used to classify children with language impairments of unidentified origin; the CATALISE (Criteria and Terminology Applied to Language Impairments: Synthesizing the Evidence) studies addressed this by recommending DLD as a standardised term for a persistent language disorder of unknown cause that significantly impacts a child’s social interactions, academic performance and everyday communication.1 2
DLD is generally diagnosed around the age of four or five,3 as many children with early language delays, often referred to as ‘late talkers’, tend to catch up by the age of three without any lasting language difficulties.3 4 However, children with DLD experience persistent language challenges that may not improve significantly over time without effective intervention. Although DLD is typically diagnosed later, early signs such as delayed use of gestures, limited vocabulary and difficulty understanding language often emerge at a younger age.3 5 Recognising these early symptoms is essential for timely intervention.6 7
DLD is recognised globally in children, regardless of linguistic or cultural background.8 The prevalence of DLD varies widely across countries due to differences in diagnostic criteria, screening tools and population characteristics.9 According to a systematic review, it was estimated that 6% of children in the UK aged between 2 years and 5 years had or were at risk of DLD.10 In the USA, the prevalence among children aged 5–6 years was reported as 7.4%.11 In Argentina and Thailand, 11.6% of 2-year-old children were identified as being at risk of DLD, compared with 13.4% in Australia.12–14 A more recent study in Australia found the prevalence of DLD among 10-year-olds to be 6.4%.15 In India, 6% of children aged 0–36 months were considered at risk of DLD.16 Meanwhile, in China and the UAE, the prevalence among toddlers aged 3 years was 3% and 9.9%, respectively.17 18
Different risk factors have been linked to DLD, including, but not limited to, sex, preterm birth, low birth weight, history of speech and language delay in the family, socioeconomic status of the parents, chronic otitis media, larger family size and a later birth order.19–21 A recent scoping review by Sansavini et al identified key early predictors and risk factors for DLD. The most notable early predictors include delays in gesture production, receptive and expressive vocabulary, syntactic comprehension and word combinations by 30 months of age. A family history of DLD was identified as the strongest risk factor, while low socioeconomic status and limited environmental input also contributed but with less predictive value.3 However, owing to inconsistent results from different studies, the United States Preventive Services Task Force failed to create a definitive list of DLD risk factors to guide primary care physicians in selective screening.19
Arab countries have unique linguistic and cultural factors that may influence the identification, diagnosis and management of speech and language delays. However, the literature on the prevalence and risk factors for DLD in the Arab world remains limited and fragmented.17 22 23 The absence of comprehensive epidemiological data on DLD in these countries makes it difficult to accurately assess the true burden of the condition. Therefore, this scoping review summarises the existing literature and provides a comprehensive narrative assessment on the epidemiology of DLD among children aged ≤10 years in the Arab countries, encompassing both children diagnosed with DLD and those at risk of developing the disorder. Mapping the available research is essential to identify gaps in the current epidemiological understanding of DLD. The findings can inform future theoretical investigations by highlighting understudied areas and motivating further research. They can also support policymakers in directing resources towards research-informed interventions and future studies that address the specific developmental needs of children in the Arab countries.
Methods
This scoping review was conducted and reported following the 2018 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Extension for Scoping Reviews (PRISMA-ScR) guidelines.24
Inclusion and exclusion criteria
The population, exposure, comparator and outcomes (PECO) statements, which propose a framework from which studies are identified and selected for inclusion, were used to construct the eligibility criteria. This structured approach allows for a clear definition of the key components of the review, ensuring that the included studies are relevant and that the evidence gathered can be effectively translated into practice.
Our outcome of interest was DLD. Thus, we included any study where the primary or secondary outcome involved DLD, taking into account the variability in terminology used in the literature to describe this condition. Accordingly, studies that used terms such as ‘primary language disorder’, ‘primary language impairment’, ‘communication delay’ and ‘specific language impairment’ were also included.
Studies were deemed eligible for inclusion if the study population consisted of male or female children aged ≤10 years from any of the following 22 Arab countries (ie, members of the Arab League): Algeria, Bahrain, Comoros, Djibouti, Egypt, Iraq, Jordan, Kuwait, Lebanon, Libya, Mauritania, Morocco, Oman, Palestine, Qatar, Saudi Arabia, Somalia, Sudan, Syria, Tunisia, the UAE and Yemen.25 Included studies must be peer-reviewed and provide data on the prevalence or incidence of and/or quantified factors associated with DLD. Furthermore, the study population must be free from any medical conditions known to cause speech delay (eg, congenital cleft palate, autism spectrum disorder, cerebral palsy, childhood apraxia, global developmental delay, dysarthria, hearing loss after spoken language establishment, intellectual disability and selective mutism).
Studies were excluded if DLD was investigated among children older than 10 years or those who were 10 years old and younger mixed with an older age group and age stratification was not possible. Children aged >10 years were excluded because they were approaching the adolescent stage, which has unique characteristics.26 A study was also excluded if it was impossible to distinguish children with medical conditions known to cause speech/language delay from those without such medical conditions. Additionally, studies conducted on Arabic populations outside the Arab League countries, abstracts and conference papers were excluded from this study. No restrictions were imposed on the publication date. Only studies published in Arabic and English were deemed eligible for inclusion in the review.
Literature search
Based on presearches in PubMed and PubMed’s medical subject headings (MeSH) and grounded on the predefined PECO inclusion and exclusion criteria, a broad search for literature was conducted between 10 April 2023 and 18 April 2023. The search string was later updated on 22 October 2024. Three biomedical databases were included in this study: PubMed, Scopus and Web of Science. A combination of search fields (title, abstract, keywords and MeSH/thesaurus) was used to ensure that all possible evidence on the topic was identified. Finally, Google Scholar was manually searched, and the references of the included studies were screened by a single reviewer (GSMA-B) to identify additional eligible studies not captured by the three primary databases.
Database citations were imported into the systematic review tool Covidence,27 in which the automatic deduplication function was used to identify unique records. A detailed search log with the results, notes and reproducible search strings for each database is presented in online supplemental file 2.
Supplemental material
Screening and selection
Using Covidence’s blinded screening features, two reviewers (GSMA-B and AA) independently screened all records identified in the three databases. Title and abstract screening were first performed, followed by full-text screening. Discussions between the two reviewers (GSMA-B and AA) resolved any disagreements. A PRISMA flow diagram was used to report the specifics of the screening and selection procedure.28
Data extraction
Data were extracted from eligible studies using the predefined criteria provided in online supplemental file 3. Data extraction was performed independently by two authors (GSMA-B and AA). The corresponding authors of eligible studies with insufficient information were contacted via email. The following data were extracted from relevant studies: author names, publication year, country and city where the study was conducted, study design, setting, number of participants, data collection method, mean age of study participants, tool used to diagnose speech/language delay, number and proportion of participants diagnosed with DLD and different risk factors with 95% CIs if available.
Supplemental material
The risk factors identified as linked to DLD were grouped into maternal and perinatal factors, factors related to children and family and environmental factors. Maternal and perinatal-related risk factors include complications during pregnancy and delivery, such as forceps use, preterm birth, caesarean section, maternal health issues and lower maternal education. Child-related risk factors, on the other hand, include aspects directly associated with the child, such as age, gender, low birth weight, birth order and health conditions like cyanosis and impaired motor development. Family-related and environment-related risk factors encompass the broader context, including family history of language delay, parental socioeconomic status, interaction levels and environmental factors like screen time, breastfeeding and living conditions.
Synthesis of results
This study aimed to summarise the existing literature and provide a comprehensive narrative assessment on the epidemiology of DLD among children populations aged ≤10 years in the Arab countries. Consequently, we performed descriptive analyses of the relevant variables and described the findings according to the reported prevalence and risk factors for DLD in different countries. Formal quality assessment of the included studies was not performed because it was not part of the overall aim of this review. However, the Critical Appraisal Skills Programme assessments for each study are provided as online supplemental material.
Supplemental material
Patient and public involvement statement
Patients or the public were not directly involved in the conception, design and planning of this study.
Results
Identified and excluded studies
Following the removal of duplicates, our initial search across the three databases resulted in 4832 citations for screening titles and abstracts. Subsequently, 42 studies remained for full-text screening. Finally, 32 studies were excluded after full-text screening. Reasons for exclusion were ‘wrong outcomes’ (n=15), which included studies that did not assess DLD as an outcome measure; ‘wrong patient populations’ (n=12), which included studies involving individuals with medical conditions known to cause speech delays, such as autism spectrum disorder or intellectual disability, as well as studies that focused on Arab communities located in non-Arab countries and studies with patients older than 10 years; ‘wrong study design’ (n=2) which primarily comprised abstracts without full text and ‘duplicates’ (n=3). Seven more papers were added after examining the reference lists of the included articles and conducting Google Scholar searches. Finally, 17 research articles were deemed eligible for inclusion in this scoping review, all of which were written in English. The flowchart of the entire searching process is shown in figure 1.
Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram.
Descriptive characteristics of the included studies
Descriptive characteristics of the included studies are summarised in tables 1 and 2. Of the 17 included studies, eight (47.1%) were from Egypt,23 29–35 four (23.5%) from Saudi Arabia,22 36–38 two from the UAE17 39 and two from Iraq.40 41 Another study included mixed populations from Lebanon, Palestine, Jordan and Egypt.42 The earliest study was published in 2004 in the UAE,17 and the recent study was published in 2024 in Egypt.35
Summary of studies reporting prevalence of developmental language disorder
Summary of studies reporting risk factors associated with developmental language disorder
Except for one study in which the aim was to develop free tools that enable parents and professionals to predict children’s early language abilities,42 all the primary objectives of the included studies were mainly aimed at assessing DLD prevalence or identifying risk factors. Most of the included studies used a cross-sectional design (82.4%, n=14), and only three used a case-control design.31 32 39 In contrast to the majority, two studies employed online methods for data collection,38 42 whereas others used face to face interviews or lacked clarity on their data collection methods. The ages of the children included in the 17 studies ranged from 8 months to <7 years. The heterogeneity in the methodologies of the included studies was also evident in the screening tools used for DLD. Some studies employed standardised tools such as the Denver Developmental Screening Test,17 the Arabic Ages and Stages Questionnaire22 36 and the Arabic language test,33 while others relied on assessments conducted by physicians or tailored questionnaires developed by the authors (tables 1 and 2).23 31 41
DLD prevalence in Arab children
In nine studies conducted across Egypt, Saudi Arabia, the UAE and Iraq, the reported prevalence of DLD in children ranged from 3.2% in Egypt to 25.6% in Saudi Arabia.17 22 23 30 33 34 36 37 40 Samples were drawn from various settings, including communities,17 22 34 nurseries23 and hospitals or clinics.30 33 36 37 39 40 To estimate the prevalence, three of the nine studies employed a stratified random sampling technique,17 23 34 while five relied on convenience sampling.30 33 36 37 40 The UAE study focused on children aged 3 years, with the sample drawn from households, whereas the Iraq study involved 353 children under 7 years old, sampled from a hospital setting. In Egypt, the reported prevalence ranged from 3.2% to 19.7%, with sample sizes varying between 212 and 21 316.23 30 33 34 In Saudi Arabia, the reported prevalence ranged from 5.6% to 25.6%, with sample sizes between 250 and 948.22 36 37
DLD risk factors in Arab children
14 studies investigated the potential associations between various risk factors and DLD in Arab children. These studies were conducted in Egypt, Jordan, Palestine, Lebanon, the UAE, Saudi Arabia and Iraq.17 22 29 31–35 37–42 Of these, 11 used cross-sectional designs,17 22 29 33–35 37 38 40–42 while three employed case-control designs.31 32 39 Statistical methods varied across the studies: a predictor model was applied in a mixed population study involving Lebanon, Jordan and Egypt42; χ2 tests were used in studies from Saudi Arabia, Iraq and Egypt22 33 37 40 41; regression models were applied in six studies17 31 32 34 38 39; one study from Egypt, focusing on children from hospital settings, used a correlation analysis.29
Maternal and perinatal-related risk factors
History of delivery problems,32 34 use of forceps in delivery,22 preterm delivery, caesarean section31 and pregnancy-related diseases of mothers32 were identified as potential risk factors for DLD. Additionally, in a case-control study conducted in Egypt, consanguineous marriage was significantly associated with DLD.31 Lower maternal education was reported in four studies as being significantly associated with DLD,22 32 34 35 and the previous non-UAE nationality of the mother was also identified as a risk factor for the UAE.17
Child-related risk factors
Three studies reported that younger children were more likely to have DLD than older children.22 38 42 Furthermore, five studies found that boys were more likely to have DLD than girls.22 31 34 40 42 Exposure to cyanosis was reported as a risk factor for DLD in two studies.31 34 Additional risk factors identified in single studies included the child’s country of origin,42 neonatal intensive care unit admission, postnatal convulsion,34 impaired motor development,32 birth order and low birth weight.31
Family and environment-related risk factors
The most common family risk factors reported in this scoping review were a family history of language delay22 31 40 and a lower total monthly income of the family.17 32 The following are other family and environmental risk factors identified in this study: lower socioeconomic status,29 parents’ work status, lack of siblings,22 living in urban areas,31 34 early introduction of complementary food,32 children who were not breastfed,37 lower parents’ interaction score,31 mothers spending less than 2 hours with the child daily, children spending most of their time playing alone or playing with electronic devices, children watching more than 4 hours of TV daily,22 39 41 poor screen media context, longer screen time, less reading prevalence and poor media quantity.38
Discussion
This scoping review summarises the reported prevalence and risk factors of DLD in children aged ≤10 years in the Arab countries, including both children diagnosed and at risk of developing DLD. This study included 17 research articles, yielding nine reported estimates of DLD prevalence in seven Arab countries. The median reported prevalence of DLD was 11.9%. The lowest prevalence was reported in Egypt (3.2%) and the highest in Saudi Arabia (25.6%).30 37 The prevalence of DLD varies remarkably between or within countries. For instance, in the USA, 13.5%–17.5% of children between 18 months and 36 months old have DLD.43 In India, the prevalence of DLD fluctuates among 6%, 9.5% and 27%,16 44 45 whereas in the UK, its prevalence ranges from 6% to 19%.10 46 This can be attributed to the diverse methodologies, contextual factors and differences in diagnostic criteria and tools. As a result, it is important to exercise caution when comparing or interpreting DLD prevalence between or within nations.
Studies in this review demonstrated a high degree of methodological heterogeneity, including variations in screening tools, cut-off points, age groups, sampling techniques and settings. For example, the age range of children included in our study was from 3 months to less than 7 years, which may contribute to variability in prevalence rates. Research has shown that DLD prevalence tends to vary with age. Younger children are more likely to be identified with DLD due to closer monitoring of developmental milestones, while older children may show lower prevalence rates as developmental delays resolve or adaptive strategies develop over time.3 47 Consequently, the prevalence of DLD may appear higher in younger children compared with older ones. In this scoping review, it is important to interpret the findings carefully, as we included both children diagnosed with DLD and those at risk. Younger children, particularly under 5 years, may have been identified as at risk but could simply be late talkers, potentially inflating prevalence estimates in this age group.
Using different screening tools and variations in who fills out the questionnaire can also contribute to variability in reported prevalence. For example, in the study by Gad-Allah et al, the reported prevalence of DLD was 30.8% in children who completed the speech and language screening assessment tool by their parents, in contrast to only 8.8% when the same instrument was used by teachers.23 This highlights the importance of using standardised, validated screening tools along with clear criteria and a robust methodology to guarantee that the findings are both reliable and comparable.
Research on speech and language delay in the Arab countries appears to be sparse and possibly not a priority, as evidenced by the significant time gap between published studies. The earliest study in the Arab countries to estimate risk factors for DLD was conducted in the UAE in 2004,17 whereas the most recent study was conducted in 2024 in Egypt.35 However, no studies were published between 2005 and 2011 and in 2013, 2016 and 2021. Furthermore, no studies have been conducted in Algeria, Bahrain, Comoros, Djibouti, Kuwait, Libya, Mauritania, Morocco, Oman, Qatar, Somalia, Sudan, Syria, Tunisia and Yemen. Further research is needed in the Arab region to better understand the burden of DLD.
In this scoping review, the risk factors for DLD were categorised into three distinct groups to help clarify the multiple dimensions of risks affecting DLD. It is important to recognise that these groups are interconnected and often overlap.48 49 Factors from one category may influence or be influenced by those in another. For example, maternal health and perinatal complications (from the maternal and perinatal group) can have direct effects on a child’s biological development (child-related factors), while the family’s socioeconomic status or parental interaction levels (family and environmental factors) can mediate the impact of both maternal health and the child’s development.
Most of the DLD risk factors identified in this scoping review are consistent with those described by other studies, including sex, history of speech or language impairment in the family, parents with less education and several perinatal risk factors such as prematurity, labour complications and low birth weight.3 20 21 50 51 Four separate studies conducted in Saudi Arabia, Iraq and UAE reported a significant correlation between screen time and content and children’s speech and language development.22 38 39 41 The negative effects of media overuse and poor content on children’s speech and language are now widely acknowledged and observed in different global studies.52 53 This may explain why, in 1998, children living in urban areas performed higher on speech and language tests than those living in rural areas.54 However, in 2018 and 2023, when media usage among urban youth increased, living in an urban area was identified as a risk factor for DLD.31 34
A study included in this scoping review from the UAE reported that children are at a higher risk of DLD when their mother is of a different nationality than their father.17 However, a systematic review by Hambly et al shows limited evidence to support the idea that multilingual children, in general, develop language at a slower pace compared with their monolingual peers.55 This discrepancy may be attributed to the stress experienced by minority mothers or the potential for over-diagnosis when multilingual children are assessed in a language they haven't fully mastered, using monolingual norms.
Most of the included studies (82.4%, n=14) used cross-sectional designs. Of these, four employed random sampling techniques,17 23 34 42 and only one study was conducted at the population level.34 No cohort studies were included in this scoping review, underscoring a significant gap in the literature. Large prospective cohort studies to identify DLD risk factors in Arab countries are needed.
Strengths and limitations
The strength of this study lies in the fact that, to the best of our knowledge, this is the first research to collect and summarise all data available in the published literature on the prevalence and risk factors of DLD in the Arab countries in children aged ≤10 years. This study closely adhered to the PRISMA-ScR guidelines, and the chance of human error was minimised by two independent reviewers who performed screening and data extraction. This study was successfully able to identify gaps, particularly the dearth of information regarding DLD prevalence and risk factors throughout the Arab countries and recommend future research.
However, we acknowledge some limitations of this study that should be considered when interpreting the findings. First, although 17 papers were included, there was an unequal distribution of these studies among the Arab countries. Moreover, 15 (68.2%) Arab countries were completely absent, which potentially impacted the generalisability of the results. Second, owing to the scarcity of studies conducted in the Arab countries, multiple studies identified through reference lists were included in our study despite the lack of sound methodology. Third, we were unable to subcategorise DLD into speech, expressive language or receptive language delays because of a lack of available data and unclear terminology in the reviewed studies.
In conclusion, data on DLD in Arab children remain limited. This scoping review found that the prevalence of DLD across Arab countries ranged from 3.2% to 25.6%. While recent studies in the region have increased compared with earlier years, much more research is needed, particularly in countries where no studies on DLD have been conducted at all. Given the large heterogeneity of the studies included in this review, conducting a systematic review and meta-analysis at this point is challenging. Therefore, a unified screening tool for DLD is essential to ensure data reliability and comparability. Additionally, comprehensive nationwide studies are needed to determine the prevalence of DLD, and further longitudinal cohort studies are required to better understand its risk factors and support the development of targeted interventions.
Data availability statement
Data sharing not applicable as no datasets generated and/or analysed for this study.
Ethics statements
Patient consent for publication
Ethics approval
Not applicable.
References
Footnotes
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Contributors GSMA-B: conceptualised the study objectives and design, created the search strings, performed screening, data extraction and contributed in drafting the manuscript and approved the final submitted version. AA: conceptualised the study objectives and design, performed screening, data extraction and contributed in drafting the manuscript and approved the final submitted version. AM: conceptualised the study objectives and design and contributed in drafting the manuscript and approved the final submitted version. RHA-R: conceptualised the study objectives and design and contributed in drafting the manuscript and approved the final submitted version. IE: conceptualised the study objectives and design and contributed in drafting the manuscript and approved the final submitted version. LAA: conceptualised the study objectives and design and contributed in drafting the manuscript and approved the final submitted version. Guarantor is GSMA-B. Chat GPT Artificial intelligence tool was used solely for checking the English language, ensuring that the sentences are free from spelling and grammatical mistakes. No AI assistance was employed for content creation, data analysis or interpretation in this work.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests None declared.
Patient and public involvement Patients and/or the public were not involved in the design, conduct, reporting or dissemination plans of this research.
Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.