Translation and language validation of the Epworth sleepiness scale for children and adolescents (ESS-CHAD) into Brazilian Portuguese

Objective This study aimed to translate the Epworth sleepiness scale for children and adolescents (ESS-CHAD) into Brazilian Portuguese. Material and Methods The translation and language validation processes were carried out through translation, back translation, technical review, assessment of verbal comprehension/clarity of the scale by experts (four pediatric neurologists). After they have reached a final version of the ESS-HAD a sample of asymptomatic children and adolescents that were participants in another sleep project were invited to read and complete the questionnaire to evaluate comprehension by the aimed population. Results Two independent researchers made the forward translation and it has around 90% of concordance. Minor disagreements were related to the position of adjectives in the sentence. No major difficulties were reported by the 3rd researcher that performed the back translation. After a consensus meeting with the four participants, we have reached a final version of the questionnaire. In the cognitive interviews, the scale was reportedly easy to understand to the 23 respondents. One adolescent suggested clarifying whether question 2 (likelihood of falling asleep watching TV or a video), referred to daytime or nighttime. The total ESS-CHAD score in this asymptomatic sample varied from 0-17, a mean score of 7.08±5.65. Discussion The final version of the ESS-CHAD in Brazilian Portuguese was approved by the copyright owners and was well understandable by caregivers and adolescents. More studies are now necessary to use this questionnaire in a larger target population to verify its validity and internal consistency.


INTRODUCTION
The term excessive daytime sleepiness (EDS) refers to unintended daytime sleep episodes. It is defined as "the tendency to fall asleep at times and under circumstances when the intention and expectation is to remain awake" and is truly different from naps that occur after lying down purposefully. EDS should also be distinguished from other tendencies or aspects of sleep habits, such as being hard to wake in the morning 1,2 .
For the adult population, a variety of laboratory-based methods are available to measure sleepiness and EDS such as the multiple sleep latency test (MSLT) and the maintenance of wakefulness' test (MWT). Whilst for children there is no consensus on how these symptoms should be evaluated 3 .
In 1991, Johns 4 proposed a new method for measuring daytime sleepiness, the Epworth sleepiness scale (ESS) and this brief, easy to apply questionnaire, became a tool of worldwide use to evaluate EDS not only on clinical scenarios but also in research. The ESS is an 8-item self-report questionnaire assessing the likelihood of falling asleep in specific everyday situations, thus evaluating an individual's level of daytime sleepiness. The responses are done on a four-point Likert scale (0-3). The original scale has been translated to Brazilian Portuguese by Bertolazi et al. (2009) 5 and showed good equivalence with the English version in detecting daytime sleepiness.
The adult ESS is not suitable for young children and even for adolescents. As an example, it should be implied that sleepiness during traveling in a car refers to them as passengers rather than drivers and alcohol questioning is probably not useful for the majority of responders. Although the ESS is subject to copyright (©MW Johns, 1990Johns, -1997, many non-authorized adaptations are available, some of which involved minimal changes but others suffered substantial modifications. Under the auspices of copywriter, owners Wang et al. 1 have adapted the ESS for children and adolescents. They have launched the official version of "Epworth sleepiness scale for children and adolescents" (ESS-CHAD) on 2017. The original options not useful for children such as "sitting quietly without alcohol consumption, driving, and taking part in a meeting" were replaced by "sitting by yourself after lunch", "sitting as a passenger in a car or a bus", "sitting in a classroom at school".
To have reliable and consistent measure of sleepiness in adolescents is important as there are consistent evidences that sleepiness at this age period is linked to issues related to physical and mental health and also poor academic performance [6][7][8][9][10][11][12] . Although some other scales are available in Portuguese to measure daytime sleepiness, such as the "the pediatric daytime sleepiness scale (PDSS)" 13,14 , to have another option to evaluate sleepiness in children and adolescents, using a tool that is widely accepted worldwide would also be helpful to clinicians and researchers.
The aim of this article was to translate to Brazilian Portuguese the official version of ESS-CHAD with authorization by the copyright owners.

MATERIAL AND METHODS
The first step of the process was to ask permission to translation from Mapi Research Trust (copyright owner).
This modified ESS for use in children and adolescents is brief and self-administered. Each question can be scored from 0 (no chance of falling asleep) to 3 (high chance of falling asleep), and a score higher than 10 suggests excessive daytime sleepiness, with a linear correspondence between scores and daytime sleepiness ( Table 1). Table 1. Scores of EES-CHAD.

Score
Significance 0-5 Lower normal daytime sleepiness 6-10 Higher normal daytime sleepiness [11][12] Mild excessive daytime sleepiness [13][14][15] Moderate excessive daytime sleepiness [16][17][18][19][20][21][22][23][24] Severe excessive daytime sleepiness The translation of EES-CHAD to Brazilian Portuguese was in agreement with the methodology proposed the copyright owner (Mapi Research Trust) and followed the steps suggested by Acquadro et al. (2004) 15 . Those steps include forward translation, backward translation, review by clinicians, cognitive interviews and international harmonization. Four pediatric neurologists with different expertise on sleep medicine participated in the process, two of them performed the forward translation, the third did the back translation and the 4 th coordinated the whole process and solved minor disagreements. In order to verify if the final version was easily understandable by adolescents and caregivers, we have invited participants of another ongoing study to answer the scale, independently. The last step is used only if more than one language is involved, which was not the case of our proposal.

Agreement and authorization -Ethical aspects
A user license agreement special terms (number 34385) was issued between Mapi Research Trust, the author MLN and the Pontifical Catholic University of Rio Grande do Sul. On April 20 th , 2021 a permission to start the translation process was issued. On July 19 th , 2021, through the request 2104360 to ePROVIDE™ the authors were allowed to submit the translation process as an article.
Responders of the cognitive interview were participants of the project "Sleep quality among parents and their children during COVID-19 pandemic", approved by the institutional ethical committee and registered on Plataforma Brasil under the number 30748320.5.0000.5336.

RESULTS
The complete translation process is detailed on Table 2. 1. Forward translation: two pediatric neurologists fluent in English made the forward translation. Subsequently, both translations were discussed between the authors until agreement on the most adequate Portuguese version. The translations had around 90% of concordance and minor disagreements were related to position of adjectives in the sentence. In this step a senior pediatric neurologist conducted the discussion and decided in case of disagreement the for the best version.

Backward translation: the back translation was performed by a Brazilian Pediatric Neurologist fluent in English.
According to the ratings proposed by Acquadro et al. (2004) 15 to describe the difficulty of translating the wording of the source document, the level of difficult found by the translator was scored as 1 (no difficulty: no problems expected in developing a rendering that faithfully captures a concept that is equivalent to the source text).
2.1. Review by clinicians: all authors have independently reviewed the final Portuguese version. Finally, in a consensus meeting, the most accurate translation was chosen, considering the best conceptual, semantic, and cultural equivalences.
2.2. Cognitive interviews: to evaluate comprehension by the aimed population 23 asymptomatic children and adolescents were asked to read and complete the questionnaire. In one case, the mother of a four-year-old child completed the scale. The scale was reportedly easy to understand.
One adolescent suggested to clarify whether question 2 (likelihood of falling asleep watching TV or a video), referred to daytime or nighttime. Table 3 shows the results of the questionnaires answered for the cognitive interviews. Participants' age varied from 4 to 15 years, mean age of boys was 10 years (median 11-12 years) and for girls 11 years (median 11 years). There was a predominance of girls responders' (65.2%). In all situations proposed the chance of falling asleep varied from 0 to 3, except on the last one (chance of falling asleep while eating a meal) where all responders answered never. The mean score for each situation was: sitting and reading = 1, sitting and watching TV or a video = 1.08, sitting in a classroom at school during the morning = 0.78, sitting and riding in a car or bus for about half an hour = 1.73, lying down to rest or nap in the afternoon = 1.5, sitting and talking to someone = 0.04, sitting quietly by yourself after lunch = 1.03, sitting and eating a meal = 0. The total ESS-CHAD score varied from 0-17, mean score 7.08±5.65.  The final version of the ESS CHAD scale translated to Brazilian Portuguese was sent to Mapi Research Trust, was approved and can be obtained at (https://eprovide.mapi-trust. org/instruments/epworth-sleepiness-scale-child-adolescent 16 ).

DISCUSSION
In this study, we have translated to Brazilian Portuguese the official version of the ESS-CHAD. All steps recommended by Mapi Research Trust (copyright owners) were followed. It is worthy to have a Brazilian Portuguese version of this instrument as this questionnaire is based in the well-established and wellvalidated adult ESS. It is fairly known that many questionnaires are available to evaluate sleep in pediatric ages 13,14,17 . However, this modified version, with questions very similar to those of the adult ESS, might be useful not only to screen patients but also for clinical research.
An objective way to measure excessive sleepiness during the day is useful as previous studies have pointed to an increase of sleep disorders in adolescents, where a sleep phase delay is characteristic and this symptom could indicate a shorter sleep duration or unfavorable sleep quality. In children and adolescents, it might be associated, as consequences, with learning and behavioral problems and attention disorders [10][11][12][18][19][20] . Further, sleepiness can also be a pathway linking race and socioeconomic status with worse academic and cognitive outcomes in middle childhood 21 .
One advantage of the ESS-CHAD over the PDSS is the fact that the first has a cutoff point that differentiates normal daytime somnolence to abnormal, whilst PDSS shows a measure of association, being higher scores related to more diurnal somnolence 6 .
The psychometric analysis of the ESS-CHAD was previously described by Janssen et al. (2017) 22 . They found that this scale is a reliable and internally valid measure of daytime sleepiness for adolescents with an age range between 12-18 years old.
During the COVID-19 pandemic, many studies had evaluated sleep in children/adolescents 11,12,23 . Bruni et al. (2021) 11 found a big delay in the sleep-wake schedule in all age groups as well as an increase of sleep disturbances, in a large cohort of Italian children and adolescents. A similar study developed in southern Brazil including dyads of parents and children observed excessive daytime somnolence in almost 10% of the group with 4-12 years of age 23 . The increase in sleep disorders during the pandemics was observed worldwide and instruments to screen the pediatric population are very useful to establish an adequate clinical approach during the follow up.
The final version of the ESS-CHAD in Brazilian Portuguese was approved by the copyright owners and was well understandable by caregivers and adolescents that participated in this project. More studies are now necessary to use this questionnaire in a larger target population to verify its validity and internal consistency.  1  2  2  3  3  0  1  0  10  HNDS   13  F  1  1  1  2  3  0  1  0  9  HNDS   9  F  1  0  3  2  3  0  2  0  11  MEDS   8  F  2  0  1  3  3  0  3  0