Communicative performance and vocabulary domain in preschool preterm infants

Abstract Objective The objective of this study was to evaluate and compare the performance of children in preschool age who were born premature and term, without neurological injury, regarding receptive and expressive language skills, and to reflect on the importance of these skills for performance in preschool. Materials and Methods Two groups named Preterm Group and Comparison Group, each composed by 40 children, as well as 80 legal representatives (mothers) and 80 teachers of the participants. To pair the groups, we considered chronological age (months), sex, educational level, type of school (public or private) and socioeconomic status. To assess the groups we used structured and semi-structured Observation of Communicative Behavior and applied the ABFW Child Language Test - Part B-Vocabulary and the Peabody Picture Vocabulary Test. To assess the legal representatives we applied an anamnesis questionnaire and the MacArthur Communicative Development Inventory. The assessment of the teachers consisted of the MacArthur Communicative Development Inventory and a Student Assessment Protocol developed by the authors. Results For the observation of communicative behavior, the categories with the highest losses were: narrative, maintaining dialogic activities and attention difficulties. In the ABFW Child Language Test and Peabody Picture Vocabulary Test there were statistically significant differences. In the MacArthur Communicative Development Inventory there were statistically significant differences in expressive vocabulary, but no differences in receptive vocabulary, for both the mothers and the teachers. Conclusion Children born prematurely with low risk of neurological sequelae in preschool age may have greater difficulties in linguistic performance than their peers born to term.


Introduction
Prematurity is a relevant condition in public health, due to the variability in developmental trajectories of children, it also may cause negative academic and social-emotional repercussions 22 .
The World Health Organization (WHO) defines preterm birth as any birth before 37 completed weeks of gestation, this can be further subdivided based on gestational age: extremely preterm (<28 weeks), very preterm (28 -<32 weeks) and moderate to late preterm (32 -<37 weeks) completed weeks of gestation 19 .
Premature infants are born in a fragile condition, which often places them in a risk situation, not only regarding survival, but also possible deficits in the overall development, specifically, language and learning. This type of deficit can manifest later in life, such as in school age 13,14,17,18,21,25 .
Despite being widely recognized, the relation of this issue on school performance, as well as the nature of learning difficulties, are not yet fully understood 25,28 .
The development prognosis of preterm infants depends on the interaction of biological and environmental factors that affect the immature brain of the child. Several factors are reported as risk factors that increase the chances for changes in development, among them the presence of gestational and neonatal morbidities, gestational age, low and very low birth weight and neonatal and postnatal complications 6,21 .
The greater the number of active risk factors, the greater the potential for developmental disorders.
Many researchers focus their studies on the developmental risks of extremely premature infants and individuals of very low birth weight; however, moderate and late preterm infants are also risk individuals for such changes.
Language is crucial for communication, academic performance and social function, therefore, it must be accompanied throughout child development 24,25,30 .
Regarding the development of language, studies show that there is a high probability of developmental delay for both receptive and expressive processes for premature infants, or even that they punctuate relatively less in evaluations of these processes when compared to children born at term 3,5,11,12,16,20,22,28,29 .
However, these aspects require further studies.
Difficulties in school learning can be related to language acquisition delays. These should be identified at an earlier age, even in the absence of evidence of brain injury 2 .
Studies on language development focus on the effects of prematurity on the performance of children in preschool and other school years, due to the possibility of difficulties in cognitive skills, particularly attention and executive functions, reduced performance in language on different linguistic levels, as well as behavioral problems 1,15,17,20,30,31 .
Given this context, the objective of this study was to evaluate and compare the performance of children in preschool age who were born premature and term, without neurological injury, regarding receptive and expressive language skills, and to reflect on the effects of these for performance in preschool. which consisted of information on the social class to later perform the pairing between the groups.

Materials and methods
Teachers were contacted after the family accepted to participate in the study, they were informed about the objectives. After signing the informed consent form, we applied the MCDI 10  Peabody Picture Vocabulary Test (PPVT) 9 . The objective of this test is to assess the lexical development in the receptive field, providing information on the receptive-hearing vocabulary. We followed the rules proposed in the instruction manual to establish the base and the ceiling of the responses.
Characterization of casuistry  productions and production of words; 17.5% eye contact, protest, request and offer; 15% report and imitate. In the CG, 5% had difficulties in the narrative category and maintenance of dialogic activities. Since it refers to the receptive vocabulary, statistically significant differences were not observed, but the expressive vocabulary presented statistically significant differences for both parents and teachers. Figure 3 shows the data obtained in the Student Assessment Protocol for the PG, we note that no information was considered relevant when compared to the CG.

Discussion
The objective of this study was to verify the performance of premature infants without neurological impairment that were not identified with developmental problems, despite the risk condition of prematurity.
Literature suggests that preterm infants without major neurological impairment may have milder functional problems which often are not diagnosed until school age 6 . There are also subtle problems that can relate to communication skills, causing poor performance in language levels.

Regarding the Observation of Communicative
Behavior (Table 1)  Is he/she independent in class activities? 95 5  Regarding the replacement processes (RP), when participants in the CG were not certain of their answers, they often perform replacement processes of words, usually in the same semantic classification or designated function, for example, "pineapple" is replaced by "fruit". Participants of the PG often did not designate and did not present verbal labels that demonstrate content knowledge. We infer that in these cases, the replacement process is a development We note that our sample was restricted, and in the training of the experimental group we did not consider the classification according to the gestational age (extreme moderate or late) or birth weight, but sought infants born preterm without neurological damage and complaints of developmental disorders.
We reiterate that future studies should follow the overall development of premature infants longitudinally, to contribute to the acquisition and development of skills that will promote performance in communicative activities and learning, as well as to invest in the best indicators to monitor the specific language skills throughout the school years of premature children.
Some findings of this study seem to be congruent,