Cross-sectional research with quantitative analysis approved by the Comitê de Ética e Pesquisa (CEP, Ethics and Research Committee) of a public university in the interior of the State of São Paulo, number 1887842 on January 10, 2017.

At first the data will be presented using the global score, comparing it with the gender and age variables. Subsequently, the assessment will be described according to the receptive and expressive areas, considering the same variables and finally, a qualitative analysis will be made of the tasks with the highest number of errors during the assessment with the ADL.

The review of the score obtained in the protocols referring to the 221 children evaluated regarding ADL receptive and expressive language, 117 (52.94%) presented results within normal limits and 104 (47.06%) experienced changes. Regarding the degree of those changes, 72 (32.58%) were mild, 18 (8.14%) moderate and 14 (6.33%) severe.

The data obtained in relation with age, were statistically significant. Children over 5 years of age had a greater number of assessments within the normal range. Considering the 72 children with mild changes, 28 (38.89%) were aged 3 to 4 years and 25 (34.72%) were aged 4 to 5 years.

A relevant fact is that, out of the 14 children who experienced severe alterations, 8 (57.14%) were aged between 4 and 5 years, as shown in Table 1.

Out of the 221 children evaluated, there was a predominance of changes in the expressive language area, with 98 (44.34%) cases and the receptive area exhibited 66 (29.86%) cases.

Comparing the receptive area score with the children’s age group, the data were statistically significant, as 35 (53.03%) children aged 3 to 4 years presented a greater number of changes, as shown in Table 2.

As for expressive language, 98 (44.34%) children showed changes, with statistically significant data in relation to the age group, with 38 (38.78%) preschoolers aged 4 to 5 years showing more changes in this area, as shown in Table 3.

After quantitative analysis of the data, the tasks with the highest number of errors by preschoolers in the receptive and expressive areas were listed among the degrees of change (mild, moderate and severe), also considering the age group. The task statement to be evaluated was transcribed according to the application protocol, as described in Table 4.

Among the children evaluated in the present study, those over 5 years of age presented a greater number of evaluations that were within the normal range; this may be due to the process of acquiring language subsystems, that is, the greatest changes in younger children are related to the process of acquisition; with increasing age, there is an expansion of vocabulary and greater grammatical complexity, which would contribute to an increase in test scores and results.

The data found in this study corroborate those of Cáceres-Assenço et al. (2018), who observed a progressive increase in expressive vocabulary proportional to age; in fact 6-year-old children showed superior performance compared to 5-year-old children; Moretti et al. (2017) found higher scores in emissive and receptive tests, as the age and socioeconomic level of the children participating in their study increased.

Regarding the high number of changes in language development (47%), Santos et al. (2010), also found a high percentage of changes (38%) when investigating the association between nutritional status and language development in children aged 4 to 6 years and 11 months through the application of ADL. However, the authors do not describe the degree of changes and/or the area of language affected. In another study using the same instrument, Gouveia et al. (2020) reviewed the medical records of children aged 18 to 36 months who were followed up by a multidisciplinary team for the purpose of evaluation and family guidance, and of the 66 children evaluated, 36% presented language changes.

As to the language areas, a greater number of changes were observed in the expressive area, which is in line with the study by Silva et al. (2014). These data can be explained considering the chronology of language development, because as children progress in their development, the demands grow, especially regarding expressive aspects, since children must expand their vocabulary, evolving in terms of grammar and of symbolism mastery.

Puglisi and Befi-Lopes, (2016) highlight that children aged 4 to 6 years expand their vocabulary depending on their age, which is related to the development of morphological skills and language understanding. Therefore, it is essential that the assessment of children’s language includes the receptive and expressive areas from an early age, allowing the detection of possible changes; these findings should drive appropriate interventions to mitigate or even eliminate these difficulties.

In the receptive area, Virtuozo et al. (2018) evaluated preschoolers from a public school aged 2 to 3 years and reported that 63.33% of the participating children obtained below average results. These data differ from the findings of our study, which showed a greater number of changes in the age group of 3 to 4 years; however, this divergence may be related to the instrument used and the number of preschoolers evaluated.

With regard the age group, preschoolers between 3 and 4 years of age, followed by those aged 4 to 5, presented a greater number of mild changes, which may be related to the language acquisition phase and the age of entry into school. In fact, Law no. 12,796 (Presidência da República, 2013) set the mandatory inclusion of children in daycare centers when 4 years old. Therefore, early childhood education ceases to have a unique and exclusive nature of care, becoming a stage of great importance in the child’s school life, influencing child and language development, since this is an evolutionary process, in which the children build hypotheses and carry out various discursive exchanges with their peers and other reference adults.

It is possible that a child aged 3 years, when in a school setting, may present initial difficulties regarding this environment demands which are quite different from the family environment the only one to which the child has been exposed so far. At school, the child will have contact with other children of different age groups and reference adults, routine with different proposals, having access to different settings to be explored, increasing their understanding of the world, which will reflect on their development and should therefore use their language subsystems to understand the demands that arise in this new space, acting and expressing themselves therein.

Hence, actions that favor this process must be present in the school environment and the teacher, through playful and targeted activities, can, in a pleasurable way, provide meaningful learning, in addition to establishing a bond with the children, promoting moments of interaction, communication and socialization (Trevezani et al., 2021).

Back et al. (2019) reinforce the importance of school for language development, as it provides children with fundamental situations for the evolution of communication and language, as well as the role played by the teacher, who, in addition to being a reference adult and mediator in this framework, can observe and identify possible language difficulties.

In the present study, 72 children presented a few difficulties in the test which was considered a warning sign; the educators at the institution where the research was carried out were instructed regarding the aspects relating to language acquisition and development and potential activities were suggested that could be implemented in a school environment, since the first years of a child’s life are extremely important for the child and for the language development, considering the number of neuronal connections, brain plasticity and acquisition of new skills and functions.

It is worth mentioning that the children participating in the study who presented assessments indicating moderate and severe changes were referred for evaluation and treatment an external professional speech therapist, from the public or private network, and the parents and teachers were duly guided by another speech therapist who carried out the investigation.

Children aged 4 to 5 years who have language problems should be looked at with greater attention and care, as language changes may have an impact on the acquisition and development of future skills such as reading and writing. Some studies also report that biological risk factors, such as prematurity and low birth weight, environmental and socioeconomic factors, influence the child’s development and may hamper cognitive abilities and normal language development.

In view of the above, the importance of carrying out language assessments in children, especially in the pre-school phase, is evident; changes ought to be detected early in this process, thus helping difficulties to be worked on and losses alleviated, or even remedied, in future stages (Cáceres-Assenço et al., 2018).

Regarding the tasks used in ADL, we observed that those involving the acquisition of the plural, understanding the passive voice, pronouns, concepts of quantity and telling stories through pictures resulted in a greater number of errors on the part of the children evaluated.

With regard to the acquisition and productive use of number morphology in Brazilian Portuguese, Befi-Lopes et al. (2009) evaluated 74 children aged 3 to 6 years and 11 months and found that those with normal language development were able to identify the grammatical number morpheme and its semantic information from the age of 3, showing improvement with age, becoming productive at around 5 years of age. Regarding the plural production, the answers were detected in children aged 5 and over.

Regarding the passive voice, Borer and Wexler (1987) state that children with the expected development corresponding to the age group will understand the structure of the passive voice from 4 to 5 years of age, and that 6 years old Brazilian Portuguese speakers will understand long passive forms better.

As for pronouns, they play an important role in communication by identifying specific individuals in the discursive framework; besides, pronouns change depending on who is speaking. Children play an active role in language acquisition, as they formulate hypotheses regarding deictic terms and strategies that can be used in the communication with other people. The basic acquisition of such terms occurs, on average, until the age of 3, initially involving first and second person pronouns, with the complete acquisition of this system occurring by the age of 8 (Issler, 2013). In this regard, Cruz (2008) states that for this process to occur as expected, it is important that parents, in dialogical situations with the child, use different forms of reference, nominal and pronominal, using different forms to express deictic roles in communicative situations.

The activities of telling and listening to stories are common practices in early childhood education, contributing to the process of acquisition and development of oral language, especially with regard to vocabulary expansion. Furthermore, children’s frequent contact with books is linked to the good development of receptive vocabulary and initial reading skills (Virtuozo et al., 2018).

Motta et al. (2006) suggest that narratives can be included in the process of assessing children’s language, as they provide data on possible language difficulties that could impact future school performance. Costa et al. (2018) indicate that at the age of 5, children have greater ability to structure narratives and at 6 they understand and narrate them more skillfully, evolving throughout their school life.

Stories make up the daily lives of young children, so when they have difficulty telling or understanding them, they can miss important aspects of communication and learning (Miller et al., 2001). The children aged 5 to 6 years assessed in our study had difficulties in telling a story through pictures. Therefore, it is important that such activities are included in everyday school and family life, as the act of telling stories from books or pictures plays an important role in language development and should, therefore, be encouraged by generating interest in children.

Finally, the ADL proved to be an instrument that is easy to apply, especially in schools, and can be used with a wide age range children; however, it is worth highlighting that in our bibliographical survey we found few studies that used ADL as a research tool to evaluate the receptive and expressive domains of language, which is a limiting factor for further discussion of the this study outcome.

Among the preschool children assessed, those aged 3 to 4 years had a greater number of mild difficulties, while those aged 4 to 5 years presented more severe language changes. Regarding the area of language affected, expressive was the one with the highest number of evaluations below normal. Thus, considering the critical period for language acquisition and development, the present study highlighted the importance of carrying out language assessments in preschoolers through the use of standardized instruments. Such assessments, when carried out in schools, identify possible language changes, enabling adequate guidance for parents and teachers, as well as helping to refer children for treatment, minimizing negative impacts on the child development and learning processes.