Everyone Can Sing: Protocol for a non-randomized feasibility study of class choir as mental health promotion among primary school children (ages 6-10) in Denmark

Everyone Can Sing: Protocol for a non-randomized feasibility study of class choir as mental health promotion among primary school children (ages 6-10) in Denmark | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Everyone Can Sing: Protocol for a non-randomized feasibility study of class choir as mental health promotion among primary school children (ages 6-10) in Denmark Katrine Rich Madsen, Anne Tetens, Lars Ole Bonde, Amalie Oxholm Kusier, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6030016/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 31 Dec, 2025 Read the published version in Pilot and Feasibility Studies → Version 1 posted 5 You are reading this latest preprint version Abstract Background There is an urgent need for feasible and effective mental health promoting interventions from early childhood. High-quality music education carries the potential to promote school thriving, positive class community and social relations, which are key prerequisites for children’s mental health. However, implementation and potential benefits of this type of intervention have not yet been evaluated in the Nordic countries. The Everyone Can Sing intervention is as a class-based singing intervention that integrates class choir into the regular school schedule two lessons a week for primary school children of age 5-10 years. The lessons follow a manualised pedagogy, which combines co-teaching between the class teacher and an educated choir leader with enactive learning in a safe atmosphere, changing choir partners, musical arousal regulation, a song repertoire including movement and gestures, and choir performances in and outside school. The aim of this feasibility study is twofold: 1) To study feasibility of the implementation of Everyone Can Sing in three Danish primary schools, and 2) to study feasibility of the evaluation design. Methods A non-randomized single-group feasibility trial will be conducted from January 2024 to March 2025 among approximately 900 primary school children in grade 0 to 3 in three Danish public primary school. Six domains relating to feasibility of the intervention (barriers and facilitators of implementation, adaptability, implementation capacity, responsiveness, acceptability and signs of benefit and harms) and three domains relating to feasibility of the study design (validity of questionnaire, uncertainties in data collection and outcome measures) will be assessed. The study follows a mixed methods methodology, involving collection, analyses, and integration of data from baseline and follow-up questionnaires from students, parents and teachers as well as observations of choir and interviews with students, parents, teachers, choir leaders, Everyone Can Sing school coordinators, Everyone Can Sing management and school management at the three schools. Discussion The results of this non-randomised feasibility study will inform whether the intervention should proceed to a future, full-size effectiveness trial, return to refinement of the intervention or the evaluation design, or stop. Trial registration: ClinicalTrials.gov, ID: NCT06204029, registered January 2nd, 2024. https://clinicaltrials.gov/study/NCT06204029?cond=NCT06204029&rank=1 Mental health promotion schoolchildren choir singing class choir feasibility study primary school school well-being school-based intervention mixed methods Figures Figure 1 Figure 2 Background Approximately every fifth child in Denmark experience mental health problems, mental illness, or low levels of school thriving before the age of ten, and 15% of Danish adolescent are diagnosed with a mental disorder before they turn 18 (1–3). The prevalence of mental health problems and illnesses in children and adolescents have been on the rise globally and in Denmark during the last decades posing a significant and growing public health concern (4,5). The experience of mental health problems, low school thriving and mental illness in childhood and adolescence is a severe risk factor for school segregation (6), low grades and school dropout and affects the ability to complete an education and gain foothold in the labour market (Dalsgaard et al. 2020; Patel et al. 2007). Importantly, poor mental health is associated with increased risk of somatic and mental illnesses in the later stages of life (7,8), thereby significantly contributing to the global burden of disease among children and adolescents with a big potential spillover into adulthood (9). There is therefore an urgent need for feasible and effective mental health promoting and preventive interventions from early childhood (10). High-quality music teaching (e.g., choir singing) can promote well-being, social inclusion in school, and positive social relations among schoolchildren (11,12), which are key prerequisites for children’s mental health (13,14). However, the potential benefits of this type of intervention have not yet been evaluated in a Scandinavian context. The Everyone Can Sing (ECS) intervention was developed as a mental health-promoting, class-based choir intervention in the Danish primary school including class choir among all students in 0 to 3rd grade as part of the regular school schedule. Mental health promotion in school School-based interventions to promote child mental health has a huge potential to reach all children regardless of their social and cultural background and thereby prevent mental health problems, promote mental health and reduce inequality in health and education in the youth population (15,16). Firstly, because intervening early in life provides a unique opportunity to reach children at a critical developmental period. From a life course perspective, we know that early experiences shape the trajectory of a child’s mental health throughout the course of their life, emphasizing the importance of early intervention (17,18). Secondly, because school-based interventions have the potential to reach most children regardless of cultural or socioeconomic background as almost all children attend school and spend most of their everyday lives here (19). Universal, school-based interventions that address all children have the potential to improve the social environment and increase the mental health at a group level. Research on universal mental health promoting interventions in primary schools shows several key strategies that have proven effective. For example, the beneficial effects seem to be larger when the intervention program involves the entire school, meaning that all children, teachers, management, and parents are involved in coordinated activities (20,21). Also, social-emotional learning (SEL) programs are widely recognized for their success in enhancing students' emotional regulation, social skills, and academic performance (20). Positive school climate initiatives also contribute significantly. Establishing a culture of respect, safety, and inclusivity helps prevent bullying and discrimination, fostering an environment where all students feel valued and supported (20). Research indicates that high-quality music teaching, such as choir singing, can foster safe classroom communities and positive social relationships among students—both of which are essential for enhancing children's mental health and learning (11,12). Furthermore, previous research from Germany, Switzerland, and Finland suggests that children who are more socially challenged or more easily excluded from the class community may have special benefit of such an intervention (22–24) Choir singing and mental health Active participation in music communities from an early age can play a major role in the prevention of ill health (11,25). Therefore, it carries the potential to improve well-being across all ages (26). Numerous studies have documented the psychophysiological mechanisms underlying the mental health benefits of singing with others, such as the release of hormones like endorphins and oxytocin, as well as the positive influence of coordinated breathing and movement on heart rate variability (27–30). From a psychosocial perspective, singing with others is an exercise in active listening, both to oneself, to others, and to the interactions within the group. This active listening and the concentrated, attentive presence it fosters are considered key reasons for the mental health-promoting effects of choir singing (31). The potential social benefit is another central aspect of choir singing as health promotion. Ensuring safe class communities and fostering positive social relations among students are integral aspects of promoting mental health in school and have been shown to mitigate emotional and behavioral problems (20,32). Particularly, children who face social challenges or are at risk of exclusion from class communities may benefit significantly from music interventions in school settings (22,23). Even though many studies document the positive mental health effects of group and community singing in different contexts and with different age groups, we have found no studies that focus specifically on choir singing as an integrated part of the school schedule for school children. No systematic reviews are identified among children and adolescents in this area, even though several reviews of music therapy interventions with children with different diagnoses (e.g., children with ASD disorders, dyslexia and in hospital treatment for somatic problems) document beneficial effects on symptoms and functional impairments (33). Systematic studies of the feasibility of implementing singing and music as part of the ordinary school curriculum for primary school children and the potential positive mental health effects of participation are therefore highly warranted (34). Particularly in the early school years, there's a scarcity of research on the potential positive health effects of choir singing. This underscores the necessity for systematic studies that explore feasibility and potential mental health benefits of integrating choir singing into the school schedule of young children. Also, there is limited availability of items and scales for this young age group where responses are predominantly of adult-report rather than child-report (35). Therefore, an important aim is also to develop and validate questionnaires for children as young as five. Aim The aim of this feasibility study is to study feasibility of a school-based mental health promoting intervention (Everyone Can Sing, ECS) that integrates class choir two hours a week as part of the regular school schedule among 5-10-year-olds (grade 0-3) in the Danish primary school. The aim is elaborated in two primary aims: Aim 1: To study feasibility of the implementation of ECS in three Danish primary schools , including an exploration of potential barriers and facilitators influencing implementation, exploration of potential adaption of the intervention and motives for adaption, the capacity of providers to deliver the intervention, how participants respond to and accept the intervention, how the intervention works and what benefits or harms the participants feel they have experienced in ECS. Aim 2: To study feasibility of the evaluation design , including exploration of the validity of questionnaire and items included in baseline and follow-up questionnaires, uncertainties related to data collection and outcome measures, and exploration of change in primary and secondary outcomes between baseline and follow up to explore efficacy signals for use in future power calculations. Findings from this study will provide knowledge on the critical aspects of the intervention and the evaluation design to inform decisions about progression, which may lead to a possible refinement of the intervention or the evaluation design prior a large full scale evaluation design (36,37). Methods Study design The study is a single arm feasibility study of a one-year intervention employing a mixed methods evaluation design. The intervention period runs from January 1 st , 2024, to March 1 st , 2025, with a preparation and development phase during Fall 2023 and end of follow-up data collection by March 2025. This study protocol will be reported using the SPIRIT 2013 checklist for randomized pilot and feasibility trials” (38), which can be found in the additional file 1. The Everyone Can Sing Intervention Everyone Can Sing (ECS) is a class choir-based mental health promoting intervention targeting Danish primary school students in grades 0 to 3 (ages 5 to 10). ECS was developed in 2018 by two highly experienced choir leaders and music entrepreneurs in close collaboration with a primary school, a music school and a church choir school in the city of Albertslund, a suburb to the capital of Copenhagen. It was tested and adapted at the initial primary school as a prototype from 2018 to 2022, where it is now fully implemented as a part of the school curriculum. As depicted in the logic model of the intervention in Figure 1 (37) , the aim of the intervention is to promote 0 to 3 rd grade students’ mental health through the enhancement of school well-being, class coherence, and social inclusion. The logic model was collaboratively developed by representatives of the ECS organization and the research team. The intervention integrates class choir lessons into the regular school schedule twice a week (2 x 45 minutes). The lessons follow a manualised pedagogy, which combines co-teaching between the class teacher and an educated choir leader with enactive learning in a safe atmosphere, changing choir partners, musical arousal regulation, a song repertoire including movement and gestures, and choir performances in and outside school. The lessons are led by the trained choir leader in collaboration with the designated class teacher. This co-teacher approach facilitates regular evaluations, in which the choir leader and teacher can adjust expectations and address challenges, consistently responding to the day-to-day dynamics in the classroom. ECS employs a manualised pedagogical approach developed by an expert, academy-trained child choir leader, which places a distinct emphasis on the inclusive aspect of musical expression through body and voice, also called enactive learning. It prioritizes the creation of an inclusive and welcoming musical environment in which the technical level and song repertoire is continually adapted to the students’ abilities and ambitions. Recognizing that most children aged 1-10 have a natural inclination towards rhythmic movement, ECS incorporates gestures, choreography, and timing to establish a vibrant and playful singing community, in which the children can unfold their creative expressivity in a way that seems natural to them.The pedagogy stands out from most other school-based singing promotion programs because the focus is not on the technical skills involved in singing or curating a specific repertoire (39). This ‘subjugate paradigm’ (40) is understood as a key to restore or revitalize community singing in the public school system (41). This pedagogic approach is employed to ensure a positive and safe school environment, so all children regardless of social or cultural background can develop social and behavioral competencies central to a positive school life. This focus moves away from nurturing musical talent and centres on the joy of musicking with body and voice. The ECS intervention also has a performative element, with regular concerts in- and outside school (42,43). To support implementation of ECS, a pedagogical manual was developed in a collaboration between the principal choir leader and an ECS practice researcher, based on theories of enactive learning, mental health promotion and qualitative studies during the prototype phase. It describes the components of the ECS pedagogy (outlined above) in details with video examples. Significant aspects of the underlying theories are presented, and the manual is used in the training of new choir leaders. Setting The intervention targets students in grades 0 to 3 (corresponding to 5-10-year-olds) in Danish public primary schools. In Denmark, children start compulsory education in grade 0 in the year they turn 6 and continues school for nine years through primary (grades 1 to 6) and lower secondary (grades 7 to 9) school. The average class size in Danish schools is approximately 20 students, and most students follow the same school class through all 10 years. Public schooling is free in Denmark and attended by approximately 75% of children, with the remaining students attending private independent schools, special education schools, or homeschooling. Public schools are administered by municipalities, which have the mandate to make decisions about the economic resources and the structure of the school system within the municipality (44,45). Study population and recruitment The intervention was developed and tested as a prototype at School 1 from 2018 to 2022. In Spring 2023, two additional schools were recruited for the feasibility study, expanding the study to three primary schools with approximately 900 students in 41 classes (Table 1). This setup allows for studying long-term sustainability and consolidation of the implementation at School 1 compared to new schools' implementation and scale-up (School 2 and 3), as well as comparing implementation across three different school contexts. The two new schools were strategically recruited to be large urban and suburban public schools with several classes at each grade level, representing children across all socioeconomic groups (Table 1) including children from catchment areas with diverse proportions of children and families in vulnerable positions (e.g., proportions of bilingual students, students from low socio-economic groups, and students that receive special needs education). This approach enables exploration of whether the intervention benefits all children equally. Table 1 Description of the study population and sociodemographic characteristics of schools Expected number of classes and students a at each grade level (n) Expected number of students (n) Geographical location Student absence (%) b Students transitioned directly to secondary education (%) b School 1 Suburban 6,9 85,7 Grade 0 4 (20) 80 Grade 1 3 (20) 60 Grade 2 3 (20) 60 Grade 3 3 (20) 60 School 2 Suburban 7,7 74,4 Grade 0 4 (20) 80 Grade 1 3 (20) 60 Grade 2 3 (20) 60 Grade 3 3 (20) 60 School 3 Urban 7,3 93,8 Grade 0 4 (20) 80 Grade 1 4 (20) 80 Grade 2 4 (20) 80 Grade 3 4 (20) 80 Total (N) 42 840 a Based on average number of children in a Danish school class, b Information obtained from Statistics Denmark. Data collection The aim and research questions of this study require the collection of both qualitative and quantitative data. Therefore, the ECS feasibility study is designed according to a mixed methods methodology, which involves collecting, analyzing, and integrating quantitative and qualitative research (46,47). Table 2 provides an overview of the data collection methods corresponding to the two research aims and their specific research questions. Table 2 Overview of the data collection methods corresponding to aims and specific research questions Research questions Data collection Aim 1: Study feasibility of the implementation of the intervention RQ 1a: What potential barriers and facilitators influence the implementation of ECS? Individual and group interviews with teachers, choir leaders, school management, ECS school coordinators and management. RQ 1b: Have the schools made any adaptions of the ECS manual, and why? Individual and group interviews with teachers, choir leaders, school management and ESC school coordinators and management. Observations of ECS activities. RQ 1c: What is the capacity of providers to deliver the intervention? Individual and group interviews with school management, choir leaders, and ECS management. RQ 1d: How do students, teachers, school management and parents respond to and engage in the ECS intervention and what is their acceptability and appreciation of ECS? Follow-up questionnaires among students, teachers, and parents. Individual and group interviews among students, teachers, and school management. RQ 1e: How do the participants experience ECS, are there any signs of potential benefit or harms and how does the intervention work? Individual and group interviews with students, teachers, and choir leaders. Baseline and follow-up data from student, teacher, and parent questionnaires. Aim 2: Study feasibility of the evaluation design RQ 2a: What is the validity of the items and measures included in baseline and follow-up student questionnaires? Group interviews with the youngest students (grade 0) Observations of students completing questionnaires in class Baseline and follow-up data from student questionnaires. RQ 2b: Which uncertainties may influence data collection and outcome measures? Baseline and follow-up data from student, teacher, and parent questionnaires. RQ 2c: What is the sample size for a future full-size effectiveness trial? Baseline and follow-up data from student, teacher, and parent questionnaires. Qualitative and quantitative data will be collected across a 1,5-year period from October 2023 to March 2025, illustrated in Figure 2. Interviews and observations The qualitative data collection includes interviews with students, teachers, school management, choir leaders, ECS management and school coordinators, along with continuous observations of the ECS activities during the intervention phase. Semi-structured interview guides will be developed for all interviews and all interviews will be recorded. Additionally, observations of students completing questionnaires in class and group interviews with students are conducted to validate the student questionnaire in the preparation phase. Interviews and participant observations will take place from October 2023 to March 2025 (Figure 2). Classroom observations of questionnaire completion and focus group interviews. To ensure the inclusion of valid items and scales for children as young as five in the student questionnaires, face and content validity will be assessed through classroom observations of students completing the questionnaire among the youngest age group (grade 0 and 1, n=40) followed by cognitive group interviews with students (n=6) prior to the baseline data collection. These measures are taken to evaluate the questionnaire administration in class and identify any spontaneous issues that might arise during questionnaire completion, which may not be captured in the following focus group interviews. Results will provide knowledge on the clarity and understanding of items and measures, ensuring that the final questionnaire consists of items that students understand as intended, thereby providing valid information for the study. Observation and interview guides will be developed prior to observations and interviews to guide focus (48,49). Given the limited availability of items and scales for this age group, responses for this age group are predominantly of adult-report rather than child-report (35,50). Therefore, an important aim of this project is to develop a valid questionnaire for children as young as five. To achieve this, we will apply items that are developed and validated for this study (e.g., items relating to participant responsiveness, co-variates), items applied and validated among slightly older children (KIDSCREEN, items about school well-being from HBSC, see below) or items that are developed for the age group. Observations of ECS activities will be carried out during class choir lessons in school and during internal and external concerts throughout 2024. These observations will provide insights into the student interactions with peers, teachers, and choir leaders. Observation will be distributed across the three schools, across grades, and throughout the intervention period. An observation guide will be developed to focus the data collection, and fieldnotes will be recorded during observations (51). Interviews with students. To explore students’ experience of the ECS intervention as well as their responsiveness to and engagement in the intervention, interviews will be conducted in groups of two to three students across all grades (0-3 rd grade) evenly distributed across all three schools (n=16). Interview themes will include the experience of participating in ECS activities, as well as their perception of the impact of ECS on class coherence and the social relations within the class. The interview structure of student participation in pairs of two to three is designed to create a safe space for students to share their thoughts and experiences of ECS freely (52). The interviews will be conducted six months after ECS start-up, in Autumn 2024. Focus group interviews with teachers involved in the ECS intervention will be conducted at each school (n=6) at the end of the school year. Topics will include implementation (experience with co-teaching, barriers and facilitators of integrating ECS into the school schedule, adaptions or deviations from the pedagogical ECS manual, appreciation and acceptance of ECS), but also the teachers’ perception of the impact of ECS on their students (changes in class cohesion, students’ school well-being, mental health, unintended side effects, and changes in teaching environment). Focus group interviews with choir leaders at each school (n=3) will explore their role in the ECS intervention, their reflections on barriers and facilitators of implementation, their experience with co-teaching, and their perception of how ECS influence students. Interviews with school management will be conducted to gain insights into the feasibility of ECS implementation (n=6). Topics will include the school’s motivation for participating, implementation experiences, potential barriers to implementation, and how they were overcome. The interviews will be conducted in Spring 2024 and by the end of the intervention period. Interviews with ECS management and school coordinators will be conducted to explore their role as the link between the school and the choir leaders (n=3). Topics will include themes related to barriers and facilitators of implementing ECS. Baseline and follow-up questionnaires The quantitative data collection includes baseline (January 2024), and follow-up (January 2025) questionnaires administered to students, teachers, and parents (Figure 2) to have the perspective of both the children, their parents and other significant adults (53). These questionnaires will include standardized and validated psychometric measures as well as newly developed items. The student questionnaires will be administered electronically during a 45-minute school lesson. Questionnaires to teachers and parents will be distributed electronically and parents will also have the possibility to complete paper questionnaires in continuation of the AKS Spring concert to increase participation rate. For each student, their teacher and one parent will be asked to complete an electronic questionnaire. Potential primary outcome: Mental health The World Health Organization (WHO) defines mental health as “a state of well-being in which the individual realizes his or her own abilities, can cope with the normal stresses of life, can work productively and fruitfully, and is able to make a contribution to his or her community” (54). Mental health in children includes the normal aspects of development such as being able to take part in play and learning using their senses, motor functions, voice, and social skills, and to experience joy in doing so as part of the everyday life in school. Data on students’ mental health will be evaluated from the perspectives of both the students, their parents, and their teacher. Parent and teacher reported mental health: Mental health problems will be measured using the Strengths and Difficulties Questionnaire (SDQ) , a well-validated, highly structured, and widely used multi-informant assessment and screening instrument for child and adolescent mental health problems. Brevity and positively worded items characterize the SDQ and make it quick and easy to complete for parents and teachers. As the questionnaire can be completed by children down to 11-year-olds, information from SDQ will only be collected by parents and teachers. The SDQ consists of 25 items of positive or negative attributes of the child scored on a 3-point Likert scale, divided into five sub-scales: emotional problems, behavioral problems, hyperactivity, peer problems, and pro-social behavior (55–58). The primary outcome will be improvement in mental health problems measured by the SDQ total difficulties scale (range 0-40), which sums up the difficulties across four problem areas (not including pro-social behavior). We will also explore the reduction of the impact of mental health problems using the SDQ impact scale (range 0-10). This scale measures the distress and the interference of problems in the child’s home-life, friendships, classroom learning and leisure activities, each scored on a 4-point Likert scale (no=0, a little=1, a medium amount=2, a great deal=3). The SDQ impact scale sums up the distress and the interference of problems counting only the moderate and severe levels (0=0, 1=0, 2=1, 3=2). Thus, a 1-point reduction on the impact scale corresponds to a change from severe to moderate, or from moderate to little or no impact in one of the five important aspects of child’s life. The psychometric properties of the SDQ have been described extensively (selected studies presented at the SDQ web www.sdqinfo.org/py/sdqinfo/f0.py). Student reported mental health : Mental health is defined by WHO as "a state of well-being in which the individual realizes his or her own abilities, can cope with the normal stresses of life, can work productively and fruitfully, and is able to make a contribution to his or her community" (59) . To ensure the questionnaire covers both the hedonic and eudaimonic dimension of the children’s mental health, the well-established WHO-5 scale is included to cover the hedonic dimension (60). The WHO-5 is recommended for use among children from age nine (61) underscoring the need for exploring the validity of the scale among the ACS age group. To ensure simplicity and understanding of the main outcome mental health, two simple single items covering the two dimensions of mental health were included: One item on self-efficacy reflecting the eudaimonic dimension and one item on general well-being covering the holistic understanding (62). As ECS involves children as young as five, an important aim of this study is to explore validity of these items among the age group. Potential secondary outcomes Class coherence: Class coherence will be estimated by four items from Danish Student Wellbeing Survey among 4 to 9 grade schoolchildren (age 10-16) (63): 1. “Are you happy about your class?”, 2. “I feel I belong to my school”, 3. “Most students in my class are friendly and helpful”, and 4. “My classmates accept me as I am”, with five response categories ranging from “Never” to “very often”. The items are developed by Danish experts and researchers within the field of public health, psychology, and education research (64), and have been applied as a measure of class coherence in a Danish report by Knoop and colleagues (14). The items are not validated among 5-10-year-olds, and it is therefore a central part of this study to elucidate this. School thriving: School thriving will be measured by the single item “How do you feel about school at present?” with four response categories ranging from “I like it a lot” to “I don’t like it at all”. The item is adapted from the internal Health Behaviour in School Children study (Madsen et al. 2023; Roberts et al. 2009), which is a survey among schoolchildren aged 11-15. The item shows good convergent validity as it is highly correlated with mental health and school performance (67–69). Reliability is tested to be moderate by a test-re-rest analysis during a four-week period (70). The item is not validated among 5-10-year-olds, which is therefore an important aim of this study. Social inclusion: Social inclusion will be measured in two ways. Firstly, with two newly developed items asking the children about their social relations in class: “Who from the class do you play with the most during recess? Write between 0 and 5 names. Write only one name in each box“, and “If you could choose, who would you like to sit next to in class? You can write up to 5 names. Just write one name in each box.” These items will enable social network analyses on how the social relations and group dynamics in the school classes change (71,72). The items will only be asked the oldest children in grade 3 and 4, the youngest will have difficulties in spelling names. Secondly, social inclusion will be estimated with two single items on loneliness and bullying to capture the individual experience of being social excluded: “Do you feel alone at school” from the Danish Student Well-Being Questionnaire (63) and “Do you get teased at school in a way that makes you sad?“ from ChildYouthLife (73). Both items apply four response categories: “yes often”, “yes, sometimes”, “no” and “I don’t know”. Feasibility measures Follow-up questionnaires will include items on acceptability and appreciation of the intervention from students, teachers, and parents. Moreover, the teacher questionnaire includes questions about implementation process, adaptability, and perceived effectiveness. Co-variables Baseline questionnaires will include demographic questions to the child and their parent, such as parents’ socioeconomic position, country of birth and family background. Data analyses All interviews will be transcribed verbatim and analyzed using thematic analysis in the software program NVivo (51,74). The interviews will be anonymized. Descriptive analyses of questionnaire data will be based on the whole study population as well as on subgroups defined by the duration of their experience with the ECS intervention and students’ social and socioeconomic vulnerabilities. Specifically, the two research aims will be analyzed as follows: Aim 1: Study feasibility of the implementation of the intervention Barriers and facilitators that influence implementation will be explored through semi-structured individual and focus group interviews with teachers, choir leaders, school leaders, ECS school coordinators and management. The interview data will be transcribed and analyzed using thematic analysis to identify key perceptions and experiences, focusing on factors contributing to implementation. Analysis will be guided by the CFIR implementation framework (75). Two members of the research team will independently code a portion of the data. Adaptions to the intervention and capacity to deliver the intervention will undergo a thematic analysis based on interview data and observations of ECS activities (76). Information on how the participants respond to and engage in the intervention, as well as how they accept and appreciate it, will be collected and analyzed based on follow-up questionnaire data in combination with interview data. The experience of participating in the intervention, how it works, and early sings of potential harms or benefits will be explored by the integration of survey and interview data. Within-group change in students’ mental health, school well-being, social inclusion and perception of class coherence between baseline and 1-year follow-up will be studies in explorative analyses. We will investigate the direction and magnitude of the point estimate, calculated as mean differences for continuous outcomes and odds ratios for dichotomous outcomes. It will be considered statistically significant if the p value is less than 0.05 for the before-after comparison. While this feasibility study is not designed to estimate intervention effectiveness, it can offer signals regarding potential beneficial effect and important preliminary evidence supported by the qualitative study (77). These analyses will be supplemented with qualitative data on the students’ and teachers’ experiences of participating in the intervention. By combining these evaluations, we are better equipped to make informed decisions about progression to the effectiveness study or changes that should be made regarding choice of outcomes. Aim 2: Study feasibility of the evaluation design Validity of the outcome measures will be analyzed based on cognitive group interviews with students, observations of students completing the questionnaires combined with descriptive analyses of baseline data from students. Uncertainties and utility of the selection of the outcome measures will be analyzed in terms of administration ease, response rates at baseline and follow-up, missing data, identifying of outliers, and exploring ceiling effects. Data from students, teachers, and parents (baseline and follow-up) will be analyzed separately. The effect size for the primary outcome variable will be used to determine the required sample size for a fully powered trial. Based on a list of predefined progression criteria (Table 3), results from the study will inform the decision on whether the ECS intervention should proceed to a future, full-size effectiveness trial, return to refinement of the intervention or the evaluation design, or stop (36,37). If the criteria below are not met, the trial should not proceed to full trial before potential concerns relating to the intervention or the evaluation design are addressed. If the criteria are fully met, the trial can proceed as planned. Table 3. List of criteria for progression to full-size trial of ECS Criteria for progression relating to feasibility of the intervention Two out of three schools are willing to precede with ECS after the intervention All three schools have included class choir as an integrated part of the school schedule in grades 0-3 and have completed at least one internal or external concert. More than 50% of students and teachers agree that they wish to continue with ECS in the following school year. The qualitative interviews with students, teachers and school management in combination with the quantitative evaluation indicate a potential for positive impact of ECS on class coherence, social inclusion, school well-being and mental health. Criteria for progression relating to the f easibility of the evaluation design The items included in the final questionnaire show good content validity, low missing on outcomes variables (below 15%) and are suitable for the ECS age-group. The percentage of participants (students, teachers, and parents) completing baseline and follow-up questionnaires is minimum 75%. The exploration of change in primary and secondary outcome between baseline and follow-up indicate net benefits, and the parameter estimates can be used for calculations of power and sample-size for a future effectiveness trial. Discussion The current protocol describes a single arm feasibility study that aims to explore feasibility of a school-based mental health promoting intervention integrating class choir two hours a week as part of the regular school schedule among 5-10-year-olds (grade 0–3) in the Danish primary school. More specifically, the aims of the feasibility study are: 1) To study feasibility of the implementation of ECS in three Danish primary schools and 2) To study feasibility of the evaluation design. Results from the study will provide knowledge on the critical aspects of the intervention and the evaluation design to qualify decisions about progression. The study is to the best of our knowledge the first to explore feasibility of a high-quality school-based choir intervention with the aim to promote mental health among primary school children ages 5–10. As argued by e.g., Eldrige et al. ( 36 ) and O’Cathain et al. ( 77 ), a mixed-methods approach in feasibility studies is essential to provide nuanced and detailed knowledge for defining and testing the research aim. With this study, we aim to lay the foundation for such an approach by applying a thorough mixed-methods design, employing interviews, observations and questionnaire data from all groups involved in the study. This will provide rich and diverse insights into the evaluation of the feasibility of both the intervention and its evaluation design and subsequently qualify how to refine accordingly. Another strength of this study relates to methodological issues within the field of singing and mental health among children. As stated in the introduction, there is a need for research on the feasibility of choir singing interventions and of feasible and meaningful questionnaires among children as young as 6–10. With this paper, we wish to contribute to strengthened evidence and address the current lack of studies that explores the relation between choir singing and mental health among children and valid data collection methods among the youngest. Nonetheless, as the study does not involve a control group, certain aspects of the recruitment process such as the acceptability of randomization or becoming a control school will not be assessed ( 37 ). Randomization and frequently presents practical challenges, and an examination of this process could have been relevant to explore. Also, this study does not include schools from rural areas, small schools, and private schools, which provide other contexts for implementation. An important aim of feasibility studies is also to explore cost effectiveness of the intervention ( 37 ). However, it is beyond the scope of this study, but it will be of great importance to consider in a future study. For the estimations of efficacy signals, we assess within-group changes. However, the absence of a comparison group precludes causal inferences, and our estimates may be imprecise. A particular concern is maturation bias, as there are natural changes in mental health among young children over time, however, the incidence rate of mental health problems and disorders are usually rising with age, which may counteract the effects of maturation ( 1 ) . Declarations Ethics approval and consent to participate The ECS study will be conducted in accordance with the Danish Code of Conduct for Research Integrity and complies with national guidelines and regulation regarding consent, data protection, and ethics approval. The study is registered and approved by the Research Ethics Committee at the University of Southern Denmark (Case no. 23/70679). SDU’s REC is listed by the US Dept. of Health and Human Services, Office for Human Research Protections (OHRP) as IORG0010945. Consent will be obtained from parents on behalf of their child before participation in interviews. In accordance with the Data Protection Regulation, the project will collect questionnaire data with reference to paragraph 10, which allows researchers to collect data for research and statistical purpose if complying with the duty of disclosure. Thus, parents receive thorough information about the study sent through the school communication platform prior data collection. To accommodate parents who prefer their child not to participate in the study, they are provided the option to have their child’s data excluded from the research. Consent for publication Not applicable Availability of data and materials Not applicable. Competing interests The authors declare that they have no competing interests. Funding The ECS feasibility study is funded by TrygFonden, case no. 157603. TrygFonden has no role in the conceptualization, design, data collection, analysis, decision to publish, or preparation of the manuscript. Authors' contributions KRM is principal investigator of the ECS intervention and responsible for leading and directing the study. KRM participated in the design of the study and drafted the manuscript. AT, LOB, AOK, PJ and SA participated in the design of the study and drafting of manuscript. All authors read, revised and approved the final version of the manuscript. Acknowledgements Not applicable. References Dalsgaard S, McGrath J, Østergaard SD, Wray NR, Pedersen CB, Mortensen PB, et al. Association of Mental Disorder in Childhood and Adolescence With Subsequent Educational Achievement. JAMA Psychiatry. 2020 Aug 1;77(8):797–805. Holstein B, Henriksen TB, Rayce SB, Ringsmose C, Skovgaard AM, Teilmann GK, et al. Mental sundhed og psykisk sygdom hos 0-9-årige børn [Internet]. København: Vidensråd for Forebyggelse; 2021. 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08:56:52","extension":"html","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":174030,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-6030016/v1/1f463e66c7f9d218849ebb68.html"},{"id":91829735,"identity":"1e6764dc-d69d-45da-a1cb-fbe6cec4da1c","added_by":"auto","created_at":"2025-09-22 08:56:52","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":210070,"visible":true,"origin":"","legend":"\u003cp\u003eLogic model of Everyone Can Sing.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6030016/v1/3c873649127e0a915f0b7170.png"},{"id":91829737,"identity":"5d12cc44-9e32-4760-8d30-968c4c19bb10","added_by":"auto","created_at":"2025-09-22 08:56:52","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":120485,"visible":true,"origin":"","legend":"\u003cp\u003eTimeline of data collection and corresponding respective research questions.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6030016/v1/0deaad249014f8c0faf89a4d.png"},{"id":99545353,"identity":"19eb2843-7e9f-472d-8b50-e21aa359ad3b","added_by":"auto","created_at":"2026-01-05 16:06:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1386665,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6030016/v1/ca1df9aa-6a06-479b-93f3-0544a74f9183.pdf"},{"id":91829743,"identity":"f674653d-e869-46d8-ae20-2d4e83e32de5","added_by":"auto","created_at":"2025-09-22 08:56:52","extension":"doc","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":159232,"visible":true,"origin":"","legend":"","description":"","filename":"Additionalfile1SPIRIT2013checklist.doc","url":"https://assets-eu.researchsquare.com/files/rs-6030016/v1/c5fbbd1df41aa13fc97987d1.doc"}],"financialInterests":"","formattedTitle":"Everyone Can Sing: Protocol for a non-randomized feasibility study of class choir as mental health promotion among primary school children (ages 6-10) in Denmark","fulltext":[{"header":"Background","content":"\u003cp\u003eApproximately every fifth child in Denmark experience mental health problems, mental illness, or low levels of school thriving before the age of ten, and 15% of Danish adolescent are diagnosed with a mental disorder before they turn 18\u0026nbsp;(1\u0026ndash;3). The prevalence of mental health problems and illnesses in children and adolescents have been on the rise globally and in Denmark during the last decades posing a significant and growing public health concern\u0026nbsp;(4,5). The experience of mental health problems, low school thriving and mental illness in childhood and adolescence is a severe risk factor for school segregation\u0026nbsp;(6), low grades and school dropout\u0026nbsp;and affects the ability to complete an education and gain foothold in the labour market\u0026nbsp;(Dalsgaard et al. 2020; Patel et al. 2007).\u0026nbsp;Importantly, poor mental health is associated with increased\u0026nbsp;risk of somatic and mental illnesses in the later stages of life\u0026nbsp;(7,8), thereby significantly contributing to the global burden of disease among children and adolescents with a big potential spillover into adulthood\u0026nbsp;(9). There is therefore an urgent need for feasible and effective mental health promoting and preventive interventions from early childhood\u0026nbsp;(10).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eHigh-quality music teaching (e.g., choir singing) can promote well-being, social inclusion in school, and positive social relations among schoolchildren\u0026nbsp;(11,12), which are key prerequisites for children\u0026rsquo;s mental health\u0026nbsp;(13,14). However, the potential benefits of this type of intervention have not yet been evaluated in a Scandinavian context.\u0026nbsp;The Everyone Can Sing (ECS) intervention was developed as a mental health-promoting, class-based choir intervention in the Danish primary school including class choir among all students in 0 to 3rd grade as part of the regular school schedule.\u003c/p\u003e\n\u003cp\u003eMental health promotion in school\u003c/p\u003e\n\u003cp\u003eSchool-based interventions to promote child mental health has a huge potential to reach all children regardless of their social and cultural background and thereby prevent mental health problems, promote mental health and reduce inequality in health and education in the youth population\u0026nbsp;(15,16). Firstly, because intervening early in life provides a unique opportunity to reach children at a critical developmental period. From a life course perspective, we know that early experiences shape the trajectory of a child\u0026rsquo;s mental health throughout the course of their life, emphasizing the importance of early intervention\u0026nbsp;(17,18). Secondly, because school-based interventions have the potential to reach most children regardless of cultural or socioeconomic background as almost all children attend school and spend most of their everyday lives here\u0026nbsp;(19).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eUniversal, school-based interventions that address all children have the potential to improve the social environment and increase the mental health at a group level. Research on universal mental health promoting interventions in primary schools shows several key strategies that have proven effective. For example, the beneficial effects seem to be larger when the intervention program involves the entire school, meaning that all children, teachers, management, and parents are involved in coordinated activities\u0026nbsp;(20,21). Also, social-emotional learning (SEL) programs are widely recognized for their success in enhancing students\u0026apos; emotional regulation, social skills, and academic performance\u0026nbsp;(20). Positive school climate initiatives also contribute significantly. Establishing a culture of respect, safety, and inclusivity helps prevent bullying and discrimination, fostering an environment where all students feel valued and supported\u0026nbsp;(20).\u003c/p\u003e\n\u003cp\u003eResearch indicates that high-quality music teaching, such as choir singing, can foster safe classroom communities and positive social relationships among students\u0026mdash;both of which are essential for enhancing children\u0026apos;s mental health and learning (11,12). Furthermore, previous research from Germany, Switzerland, and Finland suggests that children who are more socially challenged or more easily excluded from the class community may have special benefit of such an intervention (22\u0026ndash;24)\u003c/p\u003e\n\u003cp id=\"_Toc160176979\"\u003eChoir singing and mental health\u003c/p\u003e\n\u003cp\u003eActive participation in music communities from an early age can play a major role in the prevention of ill health\u0026nbsp;(11,25). Therefore, it carries the potential to improve well-being across all ages\u0026nbsp;(26).\u0026nbsp;Numerous studies have documented the psychophysiological mechanisms underlying the mental health benefits of singing with others, such as the release of hormones like endorphins and oxytocin, as well as the positive influence of coordinated breathing and movement on heart rate variability (27\u0026ndash;30).\u003c/p\u003e\n\u003cp\u003eFrom a psychosocial perspective, singing with others is an exercise in active listening, both to oneself, to others, and to the interactions within the group. This active listening and the concentrated, attentive presence it fosters are considered key reasons for the mental health-promoting effects of choir singing (31). The potential social benefit is another central aspect of choir singing as health promotion. Ensuring safe class communities and fostering positive social relations among students are integral aspects of promoting mental health in school and have been shown to mitigate emotional and behavioral problems\u0026nbsp;(20,32).\u0026nbsp;Particularly, children who face social challenges or are at risk of exclusion from class communities may benefit significantly from music interventions in school settings\u0026nbsp;(22,23).\u003c/p\u003e\n\u003cp\u003eEven though many studies document the positive mental health effects of group and community singing in different contexts and with different age groups, we have found no studies that focus specifically on choir singing as an integrated part of the school schedule for school children. No systematic reviews are identified among children and adolescents in this area, even though several reviews of music therapy interventions with children with different diagnoses (e.g., children with ASD disorders, dyslexia and in hospital treatment for somatic problems) document beneficial effects on symptoms and functional impairments\u0026nbsp;(33).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSystematic studies of the feasibility\u0026nbsp;of implementing singing and music\u0026nbsp;as part of the ordinary school curriculum for primary school children\u0026nbsp;and the potential positive mental health effects of participation\u0026nbsp;are therefore highly warranted\u0026nbsp;(34). Particularly in the early school years, there\u0026apos;s a scarcity of research on the potential positive health effects of choir singing. This underscores the necessity for systematic studies that explore feasibility and potential mental health benefits of integrating choir singing into the school schedule of young children. Also, there is limited availability of items and scales for this young age group where responses are predominantly of adult-report rather than child-report (35). Therefore, an important aim is also to develop and validate questionnaires for children as young as five.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAim\u003c/p\u003e\n\u003cp\u003eThe aim of this feasibility study is to study feasibility of a school-based mental health promoting intervention (Everyone Can Sing, ECS) that integrates class choir two hours a week as part of the regular school schedule among 5-10-year-olds (grade 0-3) in the Danish primary school. The aim is elaborated in two primary aims:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAim 1: To study feasibility of the implementation of ECS in three Danish primary schools\u003c/strong\u003e, including an exploration of potential barriers and facilitators influencing implementation, exploration of potential adaption of the intervention and motives for adaption, the capacity of providers to deliver the intervention, how participants respond to and accept the intervention, how the intervention works and what benefits or harms the participants feel they have experienced in ECS.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAim 2: To study feasibility of the evaluation design\u003c/strong\u003e, including exploration of the validity of questionnaire and items included in baseline and follow-up questionnaires, uncertainties related to data collection and outcome measures, and exploration of change in primary and secondary outcomes between baseline and follow up to explore efficacy signals for use in future power calculations.\u003c/p\u003e\n\u003cp\u003eFindings from this study will provide knowledge on the critical aspects of the intervention and the evaluation design to inform decisions about progression, which may lead to a possible refinement of the intervention or the evaluation design prior a large full scale evaluation design (36,37).\u003c/p\u003e"},{"header":"Methods","content":"\u003ch2\u003eStudy design\u003c/h2\u003e\n\u003cp\u003eThe study is a single arm feasibility study of a one-year intervention employing a mixed methods evaluation design. The intervention period runs from January 1\u003csup\u003est\u003c/sup\u003e, 2024, to March 1\u003csup\u003est\u003c/sup\u003e, 2025, with a preparation and development phase during Fall 2023 and end of follow-up data collection by March 2025.\u0026nbsp;This study protocol will be reported using the SPIRIT 2013 checklist for randomized pilot and feasibility trials\u0026rdquo;\u0026nbsp;(38),\u0026nbsp;which can be found in the\u0026nbsp;additional file 1.\u0026nbsp;\u003c/p\u003e\n\u003ch2 id=\"_Toc148617129\"\u003eThe Everyone Can Sing Intervention\u003c/h2\u003e\n\u003cp\u003eEveryone Can Sing (ECS) is a class choir-based mental health promoting intervention\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003etargeting Danish primary school students in grades 0 to 3 (ages 5 to 10). ECS\u0026nbsp;was developed in 2018 by two highly experienced choir leaders and music entrepreneurs in close collaboration with a primary school, a music school and a church choir school in the city of Albertslund, a suburb to the capital of Copenhagen. It was tested and adapted at the initial primary school as a prototype from 2018 to 2022, where it is now fully implemented as a part of the school curriculum.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAs depicted in the logic model of the intervention in Figure 1\u0026nbsp;(37)\u0026nbsp;, the aim of the intervention is to promote 0 to 3\u003csup\u003erd\u003c/sup\u003e grade students\u0026rsquo; mental health through the enhancement of school well-being, class coherence, and social inclusion. The logic model was collaboratively developed by representatives of the ECS organization and the research team.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe intervention integrates class choir lessons into the regular school schedule twice a week (2 x 45 minutes). The lessons follow a manualised pedagogy, which combines co-teaching between the class teacher and an educated choir leader with enactive learning in a safe atmosphere, changing choir partners, musical arousal regulation, a song repertoire including movement and gestures, and choir performances in and outside school. \u0026nbsp;The lessons are led by the trained choir leader in collaboration with the designated class teacher. This co-teacher approach facilitates regular evaluations, in which the choir leader and teacher can adjust expectations and address challenges, consistently responding to the day-to-day dynamics in the classroom. ECS employs a manualised pedagogical approach developed by an expert, academy-trained child choir leader, which places a distinct emphasis on the inclusive aspect of musical expression through body and voice, also called enactive learning. It prioritizes the creation of an inclusive and welcoming musical environment in which the technical level and song repertoire is continually adapted to the students\u0026rsquo; abilities and ambitions.\u0026nbsp;Recognizing that most children aged 1-10 have a natural inclination towards rhythmic movement, ECS incorporates gestures, choreography, and timing to establish a vibrant and playful singing community, in which the children can unfold their creative expressivity in a way that seems natural to them.The pedagogy stands out from most other school-based singing promotion programs because the focus is not on the technical skills involved in singing or curating a specific repertoire\u0026nbsp;(39).\u0026nbsp;This \u0026lsquo;subjugate paradigm\u0026rsquo;\u0026nbsp;(40)\u0026nbsp;is understood as a key to restore or revitalize community singing in the public school system\u0026nbsp;(41). This pedagogic approach is employed to ensure a positive and safe school environment, so all children regardless of social or cultural background can develop social and behavioral competencies central to a positive school life.\u0026nbsp;This focus moves away from nurturing musical talent and centres on the joy of musicking with body and voice.\u0026nbsp;The ECS intervention also has a performative element, with regular concerts in- and outside school\u0026nbsp;(42,43).\u003c/p\u003e\n\u003cp\u003eTo support implementation of ECS, a pedagogical manual was developed in a collaboration between the principal choir leader and an ECS practice researcher, based on theories of enactive learning, mental health promotion and qualitative studies during the prototype phase. It describes the components of the ECS pedagogy (outlined above) in details with video examples. Significant aspects of the underlying theories are presented, and the manual is used in the training of new choir leaders.\u003c/p\u003e\n\u003ch2\u003eSetting\u003c/h2\u003e\n\u003cp\u003eThe intervention targets students in grades 0 to 3 (corresponding to 5-10-year-olds) in Danish public primary schools. In Denmark, children start compulsory education in grade 0 in the year they turn 6 and continues school for nine years through primary (grades 1 to 6) and lower secondary (grades 7 to 9) school. The average class size in Danish schools is approximately 20 students, and most students follow the same school class through all 10 years. Public schooling is free in Denmark and attended by approximately 75% of children, with the remaining students attending private independent schools, special education schools, or homeschooling. Public schools are administered by municipalities, which have the mandate to make decisions about the economic resources and the structure of the school system within the municipality\u0026nbsp;(44,45).\u003c/p\u003e\n\u003ch2\u003eStudy population and recruitment\u003c/h2\u003e\n\u003cp\u003eThe intervention was developed and tested as a prototype at School 1 from 2018 to 2022. In Spring 2023, two additional schools were recruited for the feasibility study, expanding the study to three primary schools with approximately 900 students in 41 classes (Table 1). This setup allows for studying long-term sustainability and consolidation of the implementation at School 1 compared to new schools\u0026apos; implementation and scale-up (School 2 and 3), as well as comparing implementation across three different school contexts. The two new schools were strategically recruited to be large urban and suburban public schools with several classes at each grade level, representing children across all socioeconomic groups (Table 1) including children from catchment areas with diverse proportions of children and families in vulnerable positions (e.g., proportions of bilingual students, students from low socio-economic groups, and students that receive special needs education). This approach enables exploration of whether the intervention benefits all children equally.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1\u003c/strong\u003e Description of the study population and sociodemographic characteristics of schools\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"607\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eExpected number of classes and students \u003csup\u003ea\u003c/sup\u003e at each grade level (n)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eExpected number of students (n)\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eGeographical location\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eStudent absence (%)\u003csup\u003eb\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eStudents transitioned directly to secondary education (%)\u003csup\u003eb\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSchool 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eSuburban\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e6,9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e85,7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e4 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e3 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e3 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e3 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSchool 2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eSuburban\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e7,7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e74,4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e4 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e3 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e3 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e3 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSchool 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eUrban\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e7,3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e93,8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e4 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e4 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e4 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;Grade 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e4 (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal (N)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 137px;\"\u003e\n \u003cp\u003e42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e840\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u0026nbsp;\u003c/sup\u003eBased on average number of children in a Danish school class, \u003csup\u003eb\u0026nbsp;\u003c/sup\u003eInformation obtained from Statistics Denmark.\u003c/p\u003e\n\u003ch2\u003eData collection\u003c/h2\u003e\n\u003cp\u003eThe aim and research questions of this study require the collection of both qualitative and quantitative data. Therefore, the ECS feasibility study is designed according to a mixed methods methodology, which involves collecting, analyzing, and integrating quantitative and qualitative research (46,47). Table 2 provides an overview of the data collection methods corresponding to the two research aims and their specific research questions.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u003c/strong\u003e Overview of the data collection methods corresponding to aims and specific research questions\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"97%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eResearch\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003equestions\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eData collection\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAim 1: Study feasibility of the implementation of the intervention\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003eRQ 1a: What potential barriers and facilitators influence the implementation of ECS?\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 51px;\"\u003e\n \u003cp\u003eIndividual and group interviews with teachers, choir leaders, school management, ECS school coordinators and management.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003eRQ 1b: Have the schools made any adaptions of the ECS manual, and why?\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 51px;\"\u003e\n \u003cp\u003eIndividual and group interviews with teachers, choir leaders, school management and ESC school coordinators and management.\u003c/p\u003e\n \u003cp\u003eObservations of ECS activities.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003eRQ 1c: What is the capacity of providers to deliver the intervention?\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 51px;\"\u003e\n \u003cp\u003eIndividual and group interviews with school management, choir leaders, and ECS management.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003eRQ 1d: How do students, teachers, school management and parents respond to and engage in the ECS intervention and what is their acceptability and appreciation of ECS?\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 51px;\"\u003e\n \u003cp\u003eFollow-up questionnaires among students, teachers, and parents.\u003c/p\u003e\n \u003cp\u003eIndividual and group interviews among students, teachers, and school management.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003eRQ 1e: How do the participants experience ECS, are there any signs of potential benefit or harms and how does the intervention work?\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 51px;\"\u003e\n \u003cp\u003eIndividual and group interviews with students, teachers, and choir leaders.\u003c/p\u003e\n \u003cp\u003eBaseline and follow-up data from student, teacher, and parent questionnaires.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAim 2: Study feasibility of the evaluation design\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003eRQ 2a: What is the validity of the items and measures included in baseline and follow-up student questionnaires?\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 51px;\"\u003e\n \u003cp\u003eGroup interviews with the youngest students (grade 0)\u003c/p\u003e\n \u003cp\u003eObservations of students completing questionnaires in class\u003c/p\u003e\n \u003cp\u003eBaseline and follow-up data from student questionnaires.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003eRQ 2b: Which uncertainties may influence data collection and outcome measures?\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 51px;\"\u003e\n \u003cp\u003eBaseline and follow-up data from student, teacher, and parent questionnaires.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003eRQ 2c: What is the sample size for a future full-size effectiveness trial?\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 51px;\"\u003e\n \u003cp\u003eBaseline and follow-up data from student, teacher, and parent questionnaires.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;Qualitative and quantitative data will be collected across a 1,5-year period from October 2023 to March 2025, illustrated in Figure 2.\u003c/p\u003e\n\u003ch3\u003eInterviews and observations\u003c/h3\u003e\n\u003cp\u003eThe qualitative data collection includes interviews with students, teachers, school management, choir leaders, ECS management and school coordinators, along with continuous observations of the ECS activities during the intervention phase. Semi-structured interview guides will be developed for all interviews and all interviews will be recorded. \u0026nbsp;Additionally, observations of students completing questionnaires in class and group interviews with students are conducted to validate the student questionnaire in the preparation phase. Interviews and participant observations will take place from October 2023 to March 2025 (Figure 2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClassroom observations of questionnaire completion and focus group interviews.\u0026nbsp;\u003c/strong\u003eTo ensure the inclusion of valid items and scales for children as young as five in the student questionnaires, face and content validity will be assessed through classroom observations of students completing the questionnaire among the youngest age group (grade 0 and 1, n=40) followed by cognitive group interviews with students (n=6) prior to the baseline data collection. These measures are taken to evaluate the questionnaire administration in class and identify any spontaneous issues that might arise during questionnaire completion, which may not be captured in the following focus group interviews. Results will provide knowledge on the clarity and understanding of items and measures, ensuring that the final questionnaire consists of items that students understand as intended, thereby providing valid information for the study. Observation and interview guides will be developed prior to observations and interviews to guide focus\u0026nbsp;(48,49).\u003c/p\u003e\n\u003cp\u003eGiven the limited availability of items and scales for this age group, responses for this age group are predominantly of adult-report rather than child-report (35,50). Therefore, an important aim of this project is to develop a valid questionnaire for children as young as five. To achieve this, we will apply items that\u0026nbsp;are developed and validated for this study (e.g., items relating to participant responsiveness, co-variates), items applied and validated among slightly older children (KIDSCREEN, items about school well-being from HBSC, see below) or items that are developed for the age group.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObservations of ECS activities\u003c/strong\u003e will be carried out during class choir lessons in school and during internal and external concerts throughout 2024. These observations will provide insights into the student interactions with peers, teachers, and choir leaders. Observation will be distributed across the three schools, across grades, and throughout the intervention period. An observation guide will be developed to focus the data collection, and fieldnotes will be recorded during observations\u0026nbsp;(51).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInterviews with students.\u0026nbsp;\u003c/strong\u003eTo explore students\u0026rsquo; experience of the ECS intervention as well as their responsiveness to and engagement in the intervention, interviews will be conducted in groups of two to three students across all grades (0-3\u003csup\u003erd\u003c/sup\u003e grade) evenly distributed across all three schools (n=16). Interview themes will include the experience of participating in ECS activities, as well as their perception of the impact of ECS on class coherence and the social relations within the class. The interview structure of student participation in pairs of two to three is designed to create a safe space for students to share their thoughts and experiences of ECS freely\u0026nbsp;(52). The interviews will be conducted six months after\u0026nbsp;ECS start-up, in Autumn 2024.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFocus group interviews with teachers\u003c/strong\u003e involved in the ECS intervention will be conducted at each school (n=6) at the end of the school year. Topics will include implementation (experience with co-teaching, barriers and facilitators of integrating ECS into the school schedule, adaptions or deviations from the pedagogical ECS manual, appreciation and acceptance of ECS), but also the teachers\u0026rsquo; perception of the impact of ECS on their students (changes in class cohesion, students\u0026rsquo; school well-being, mental health, unintended side effects, and changes in teaching environment).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFocus group interviews with choir leaders\u003c/strong\u003e at each school (n=3) will explore their role in the ECS intervention, their reflections on barriers and facilitators of implementation, their experience with co-teaching, and their perception of how ECS influence students.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInterviews with school management\u003c/strong\u003e will be conducted to gain insights into the feasibility of ECS implementation (n=6). Topics will include the school\u0026rsquo;s motivation for participating, implementation experiences, potential barriers to implementation, and how they were overcome. The interviews will be conducted in Spring 2024 and by the end of the intervention period.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInterviews with ECS management and school coordinators\u003c/strong\u003e will be conducted to explore their role as the link between the school and the choir leaders (n=3). Topics will include themes related to barriers and facilitators of implementing ECS.\u003c/p\u003e\n\u003ch3\u003eBaseline and follow-up questionnaires\u003c/h3\u003e\n\u003cp\u003eThe quantitative data collection includes baseline (January 2024), and follow-up (January 2025) questionnaires administered to students, teachers, and parents (Figure 2) to have the perspective of both the children, their parents and other significant adults\u0026nbsp;(53). These questionnaires will include standardized and validated psychometric measures as well as newly developed items. The student questionnaires will be administered electronically during a 45-minute school lesson. Questionnaires to teachers and parents will be distributed electronically and parents will also have the possibility to complete paper questionnaires in continuation of the AKS Spring concert to increase participation rate. For each student, their teacher and one parent will be asked to complete an electronic questionnaire.\u0026nbsp;\u003c/p\u003e\n\u003ch4\u003ePotential primary outcome: Mental health\u003c/h4\u003e\n\u003cp\u003eThe World Health Organization (WHO) defines mental health as \u0026ldquo;a state of well-being in which the individual realizes his or her own abilities, can cope with the normal stresses of life, can work productively and fruitfully, and is able to make a contribution to his or her community\u0026rdquo;\u0026nbsp;(54). Mental health in children includes the normal aspects of development such as being able to take part in play and learning using their senses, motor functions, voice, and social skills, and to experience joy in doing so as part of the everyday life in school. Data on students\u0026rsquo; mental health will be evaluated from the perspectives of both the students, their parents, and their teacher.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eParent and teacher reported mental health:\u0026nbsp;\u003c/strong\u003eMental health problems will be measured using the\u003cem\u003e\u0026nbsp;Strengths and Difficulties Questionnaire (SDQ)\u003c/em\u003e, a well-validated, highly structured, and widely used multi-informant assessment and screening instrument for child and adolescent mental health problems. Brevity and positively worded items characterize the SDQ and make it quick and easy to complete for parents and teachers. As the questionnaire can be completed by children down to 11-year-olds, information from SDQ will only be collected by parents and teachers. The SDQ consists of 25 items of positive or negative attributes of the child scored on a 3-point Likert scale, divided into five sub-scales: emotional problems, behavioral problems, hyperactivity, peer problems, and pro-social behavior (55\u0026ndash;58). The primary outcome will be improvement in mental health problems measured by the SDQ total difficulties scale (range 0-40), which sums up the difficulties across four problem areas (not including pro-social behavior). We will also explore the reduction of the impact of mental health problems using the SDQ impact scale (range 0-10). This scale measures the distress and the interference of problems in the child\u0026rsquo;s home-life, friendships, classroom learning and leisure activities, each scored on a 4-point Likert scale (no=0, a little=1, a medium amount=2, a great deal=3). The SDQ impact scale sums up the distress and the interference of problems counting only the moderate and severe levels (0=0, 1=0, 2=1, 3=2). Thus, a 1-point reduction on the impact scale corresponds to a change from severe to moderate, or from moderate to little or no impact in one of the five important aspects of child\u0026rsquo;s life. The psychometric properties of the SDQ have been described extensively (selected studies presented at the SDQ web www.sdqinfo.org/py/sdqinfo/f0.py).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStudent reported mental health\u003c/strong\u003e\u003cem\u003e:\u003c/em\u003e Mental health is defined by WHO as \u0026quot;a state of well-being in which the individual realizes his or her own abilities, can cope with the normal stresses of life, can work productively and fruitfully, and is able to make a contribution to his or her community\u0026quot;\u0026nbsp;(59)\u0026nbsp;. To ensure the questionnaire covers both the hedonic and eudaimonic dimension of the children\u0026rsquo;s mental health, the well-established WHO-5 scale is included to cover the hedonic dimension\u0026nbsp;(60). The WHO-5 is recommended for use among children from age nine\u0026nbsp;(61)\u0026nbsp;underscoring the need for exploring the validity of the scale among the ACS age group. To ensure simplicity and understanding of the main outcome mental health, two simple single items covering the two dimensions of mental health were included: One item on self-efficacy reflecting the eudaimonic dimension and one item on general well-being covering the holistic understanding\u0026nbsp;(62). As ECS involves children as young as five, an important aim of this study is to explore validity of these items among the age group.\u003c/p\u003e\n\u003ch4\u003ePotential secondary outcomes\u003c/h4\u003e\n\u003cp\u003e\u003cstrong\u003eClass coherence:\u003c/strong\u003e Class coherence will be estimated by four items from\u0026nbsp;Danish Student Wellbeing Survey among 4 to 9 grade schoolchildren (age 10-16)\u0026nbsp;(63): 1. \u0026ldquo;Are you happy about your class?\u0026rdquo;, 2. \u0026ldquo;I feel I belong to my school\u0026rdquo;, 3. \u0026ldquo;Most students in my class are friendly and helpful\u0026rdquo;, and 4. \u0026ldquo;My classmates accept me as I am\u0026rdquo;, with five response categories ranging from \u0026ldquo;Never\u0026rdquo; to \u0026ldquo;very often\u0026rdquo;. The items are developed by Danish experts and researchers within the field of public health, psychology, and education research\u0026nbsp;(64), and have been applied as a measure of class coherence in a Danish report by Knoop and colleagues\u0026nbsp;(14). The items are not validated among 5-10-year-olds, and it is therefore a central part of this study to elucidate this.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSchool thriving:\u003c/strong\u003e School thriving will be measured by the single item \u0026ldquo;How do you feel about school at present?\u0026rdquo; with four response categories ranging from \u0026ldquo;I like it a lot\u0026rdquo; to \u0026ldquo;I don\u0026rsquo;t like it at all\u0026rdquo;. The item is adapted from the internal Health Behaviour in School Children study\u0026nbsp;(Madsen et al. 2023; Roberts et al. 2009), which is a survey among\u0026nbsp;schoolchildren aged\u0026nbsp;11-15. The item shows good convergent validity as it is highly correlated with mental health and school performance\u0026nbsp;(67\u0026ndash;69). Reliability is tested to be moderate by a test-re-rest analysis during a four-week period\u0026nbsp;(70). The item is not validated among 5-10-year-olds, which is therefore an important aim of this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSocial inclusion:\u0026nbsp;\u003c/strong\u003eSocial inclusion will be measured in two ways. Firstly, with two newly developed items asking the children about their social relations in class: \u0026ldquo;Who from the class do you play with the most during recess? Write between 0 and 5 names. Write only one name in each box\u0026ldquo;, and \u0026ldquo;If you could choose, who would you like to sit next to in class? You can write up to 5 names. Just write one name in each box.\u0026rdquo; These items will enable social network analyses on how the social relations and group dynamics in the school classes change\u0026nbsp;(71,72). The items will only be asked the oldest children in grade 3 and 4, the youngest will have difficulties in spelling names.\u003c/p\u003e\n\u003cp\u003eSecondly, social inclusion will be estimated with two single items on loneliness and bullying to capture the individual experience of being social excluded: \u0026ldquo;Do you feel alone at school\u0026rdquo; from the Danish Student Well-Being\u0026nbsp;Questionnaire (63) and \u0026ldquo;Do you get teased at school in a way that makes you sad?\u0026ldquo; from ChildYouthLife (73). Both items apply four response categories: \u0026ldquo;yes often\u0026rdquo;, \u0026ldquo;yes, sometimes\u0026rdquo;, \u0026ldquo;no\u0026rdquo; and \u0026ldquo;I don\u0026rsquo;t know\u0026rdquo;.\u0026nbsp;\u003c/p\u003e\n\u003ch4\u003eFeasibility measures\u003c/h4\u003e\n\u003cp\u003eFollow-up questionnaires will include items on acceptability and appreciation of the intervention from students, teachers, and parents. Moreover, the teacher questionnaire includes questions about implementation process, adaptability, and perceived effectiveness. \u0026nbsp;\u003c/p\u003e\n\u003ch4\u003eCo-variables\u0026nbsp;\u003c/h4\u003e\n\u003cp\u003eBaseline questionnaires will include demographic questions to the child and their parent, such as parents\u0026rsquo; socioeconomic position, country of birth and family background.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eData analyses\u003c/p\u003e\n\u003cp\u003eAll interviews will be transcribed verbatim and analyzed using thematic analysis in the software program NVivo\u0026nbsp;(51,74). The interviews will be anonymized. Descriptive analyses of questionnaire data will be based on the whole study population as well as on subgroups defined by the duration of their experience with the ECS intervention and students\u0026rsquo; social and socioeconomic vulnerabilities.\u003c/p\u003e\n\u003cp\u003eSpecifically, the two research aims will be analyzed as follows:\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAim 1: Study feasibility of the implementation of the intervention\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBarriers and facilitators that influence implementation will be explored through semi-structured individual and focus group interviews with teachers, choir leaders, school leaders, ECS school coordinators and management. The interview data will be transcribed and analyzed using thematic analysis to identify key perceptions and experiences, focusing on factors contributing to implementation. Analysis will be guided by the CFIR implementation framework (75). Two members of the research team will independently code a portion of the data. Adaptions to the intervention and capacity to deliver the intervention will undergo a thematic analysis based on interview data and observations of ECS activities (76).\u003c/p\u003e\n\u003cp\u003eInformation on how the participants respond to and engage in the intervention, as well as how they accept and appreciate it, will be collected and analyzed based on follow-up questionnaire data in combination with interview data.\u003c/p\u003e\n\u003cp\u003eThe experience of participating in the intervention, how it works, and early sings of potential harms or benefits will be explored by the integration of survey and interview data. Within-group change in students\u0026rsquo; mental health, school well-being, social inclusion and perception of class coherence between baseline and 1-year follow-up will be studies in explorative analyses. We will investigate the direction and magnitude of the point estimate, calculated as mean differences for continuous outcomes and odds ratios for dichotomous outcomes. It will be considered statistically significant if the p value is less than 0.05 for the before-after comparison. While this feasibility study is not designed to estimate intervention effectiveness, it can offer signals regarding potential beneficial effect and important preliminary evidence supported by the qualitative study (77). These analyses will be supplemented with qualitative data on the students\u0026rsquo; and teachers\u0026rsquo; experiences of participating in the intervention. By combining these evaluations, we are better equipped to make informed decisions about progression to the effectiveness study or changes that should be made regarding choice of outcomes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAim 2: Study feasibility of the evaluation design\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eValidity of the outcome measures will be analyzed based on cognitive group interviews with students, observations of students completing the questionnaires combined with descriptive analyses of baseline data from students. Uncertainties and utility of the selection of the outcome measures will be analyzed in terms of administration ease, response rates at baseline and follow-up, missing data, identifying of outliers, and exploring ceiling effects. Data from students, teachers, and parents (baseline and follow-up) will be analyzed separately. The effect size for the primary outcome variable will be used to determine the required sample size for a fully powered trial.\u003c/p\u003e\n\u003cp\u003eBased on a list of predefined progression criteria (Table 3), results from the study will inform the decision on\u0026nbsp;whether the\u0026nbsp;ECS\u0026nbsp;intervention should proceed to a future, full-size effectiveness trial, return to refinement of the intervention or the evaluation design, or stop\u0026nbsp;(36,37). If the criteria below are not met, the trial should not proceed to full trial before potential concerns relating to the intervention or the evaluation design are addressed. If the criteria are fully met, the trial can proceed as planned.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3.\u003c/strong\u003e List of criteria for progression to full-size trial of ECS\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 642px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCriteria for progression relating to feasibility of the intervention\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 642px;\"\u003e\n \u003cul\u003e\n \u003cli\u003eTwo out of three schools are willing to precede with\u0026nbsp;ECS\u0026nbsp;after the intervention\u003c/li\u003e\n \u003cli\u003eAll three schools have included class choir as an integrated part of the school schedule in grades 0-3 and have completed at least one internal or external concert.\u003c/li\u003e\n \u003cli\u003eMore than 50% of students and teachers agree that they wish to continue with\u0026nbsp;ECS\u0026nbsp;in the following school year.\u003c/li\u003e\n \u003cli\u003eThe qualitative interviews with students, teachers and school management in combination with the quantitative evaluation indicate a potential for positive impact of ECS on class coherence, social inclusion, school well-being and mental health.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 642px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCriteria for progression relating to the f\u003c/strong\u003e\u003cstrong\u003eeasibility of the evaluation design\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 642px;\"\u003e\n \u003cul\u003e\n \u003cli\u003eThe items included in the final questionnaire show good content validity, low missing on outcomes variables (below 15%) and are suitable for the\u0026nbsp;ECS\u0026nbsp;age-group.\u003c/li\u003e\n \u003cli\u003eThe percentage of participants (students, teachers, and parents) completing baseline and follow-up questionnaires is minimum 75%.\u003c/li\u003e\n \u003cli\u003eThe exploration of change in primary and secondary outcome between baseline and follow-up indicate net benefits, and the parameter estimates can be used for calculations of power and sample-size for a future effectiveness trial.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe current protocol describes a single arm feasibility study that aims to explore feasibility of a school-based mental health promoting intervention integrating class choir two hours a week as part of the regular school schedule among 5-10-year-olds (grade 0\u0026ndash;3) in the Danish primary school. More specifically, the aims of the feasibility study are: 1) To study feasibility of the implementation of ECS in three Danish primary schools and 2) To study feasibility of the evaluation design. Results from the study will provide knowledge on the critical aspects of the intervention and the evaluation design to qualify decisions about progression. The study is to the best of our knowledge the first to explore feasibility of a high-quality school-based choir intervention with the aim to promote mental health among primary school children ages 5\u0026ndash;10.\u003c/p\u003e\u003cp\u003eAs argued by e.g., Eldrige et al. (\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e) and O\u0026rsquo;Cathain et al. (\u003cspan citationid=\"CR77\" class=\"CitationRef\"\u003e77\u003c/span\u003e), a mixed-methods approach in feasibility studies is essential to provide nuanced and detailed knowledge for defining and testing the research aim. With this study, we aim to lay the foundation for such an approach by applying a thorough mixed-methods design, employing interviews, observations and questionnaire data from all groups involved in the study. This will provide rich and diverse insights into the evaluation of the feasibility of both the intervention and its evaluation design and subsequently qualify how to refine accordingly.\u003c/p\u003e\u003cp\u003eAnother strength of this study relates to methodological issues within the field of singing and mental health among children. As stated in the introduction, there is a need for research on the feasibility of choir singing interventions and of feasible and meaningful questionnaires among children as young as 6\u0026ndash;10. With this paper, we wish to contribute to strengthened evidence and address the current lack of studies that explores the relation between choir singing and mental health among children and valid data collection methods among the youngest.\u003c/p\u003e\u003cp\u003eNonetheless, as the study does not involve a control group, certain aspects of the recruitment process such as the acceptability of randomization or becoming a control school will not be assessed (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e). Randomization and frequently presents practical challenges, and an examination of this process could have been relevant to explore. Also, this study does not include schools from rural areas, small schools, and private schools, which provide other contexts for implementation. An important aim of feasibility studies is also to explore cost effectiveness of the intervention (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e). However, it is beyond the scope of this study, but it will be of great importance to consider in a future study. For the estimations of efficacy signals, we assess within-group changes. However, the absence of a comparison group precludes causal inferences, and our estimates may be imprecise. A particular concern is maturation bias, as there are natural changes in mental health among young children over time, however, the incidence rate of mental health problems and disorders are usually rising with age, which may counteract the effects of maturation (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) .\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthics approval and consent to participate\u003c/p\u003e\n\u003cp\u003eThe ECS study will be conducted in accordance with the Danish Code of Conduct for Research Integrity and complies with national guidelines and regulation regarding consent, data protection, and ethics approval. The study is registered and approved by the Research Ethics Committee at the University of Southern Denmark (Case no. 23/70679). SDU\u0026rsquo;s REC is listed by the US Dept. of Health and Human Services, Office for Human Research Protections (OHRP) as IORG0010945. Consent will be obtained from parents on behalf of their child before participation in interviews. In accordance with the Data Protection Regulation, the project will collect questionnaire data with reference to paragraph 10, which allows researchers to collect data for research and statistical purpose if complying with the duty of disclosure. Thus, parents receive thorough information about the study sent through the school communication platform prior data collection. To accommodate parents who prefer their child not to participate in the study, they are provided the option to have their child\u0026rsquo;s data excluded from the research.\u003c/p\u003e\n\u003cp\u003eConsent for publication\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003eCompeting interests\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eThe ECS feasibility study is funded by TrygFonden, case no. 157603. TrygFonden has no role in the conceptualization, design, data collection, analysis, decision to publish, or preparation of the manuscript.\u003c/p\u003e\n\u003cp\u003eAuthors\u0026apos; contributions\u003c/p\u003e\n\u003cp\u003eKRM is principal investigator of the ECS intervention and responsible for leading and directing the study. KRM participated in the design of the study and drafted the manuscript. AT, LOB, AOK, PJ and SA participated in the design of the study and drafting of manuscript. All authors read, revised and approved the final version of the manuscript.\u003c/p\u003e\n\u003cp\u003eAcknowledgements\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eDalsgaard S, McGrath J, \u0026Oslash;stergaard SD, Wray NR, Pedersen CB, Mortensen PB, et al. Association of Mental Disorder in Childhood and Adolescence With Subsequent Educational Achievement. JAMA Psychiatry. 2020 Aug 1;77(8):797\u0026ndash;805. \u003c/li\u003e\n\u003cli\u003eHolstein B, Henriksen TB, Rayce SB, Ringsmose C, Skovgaard AM, Teilmann GK, et al. Mental sundhed og psykisk sygdom hos 0-9-\u0026aring;rige b\u0026oslash;rn [Internet]. K\u0026oslash;benhavn: Vidensr\u0026aring;d for Forebyggelse; 2021. 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Cappelen Damm Akademisk; 2022. p. 97\u0026ndash;127. \u003c/li\u003e\n\u003cli\u003eBonde L, Ingerslev S. \u0026ldquo;Everyone Can Sing\u0026rdquo;: Class Choirs in the First Four Grades of Primary School and the Significance of Community Singing for Pupils\u0026rsquo; Social Well-Being and School Engagement. In 2024. p. 274\u0026ndash;94. \u003c/li\u003e\n\u003cli\u003eDanish Ministry of Children and Education. Danish Ministry of Children and Education - Primary school. 2025 [cited 2025 Jan 6]. Danish Ministry of Children and Education - Primary school. Available from: https://www.uvm.dk/folkeskolen/folkeskolens-maal-love-og-regler/om-folkeskolen-og-folkeskolens-formaal/kort-om-folkeskolen\u003c/li\u003e\n\u003cli\u003eStatistics Denmark. Statistics Denmark - Primary school. 2025 [cited 2025 Jan 6]. Statistics Denmark - Primary school. Available from: https://www.dst.dk/da/Statistik/emner/uddannelse-og-forskning/fuldtidsuddannelser/grundskole\u003c/li\u003e\n\u003cli\u003eBergman MM. 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J Child Psychol Psychiatry. 1999 Jul;40(5):791\u0026ndash;9. \u003c/li\u003e\n\u003cli\u003eGoodman R, Meltzer H, Bailey V. The strengths and difficulties questionnaire: A pilot study on the validity of the self-report version. Eur Child Adolesc Psychiatry. 1998 Oct 1;7(3):125\u0026ndash;30. \u003c/li\u003e\n\u003cli\u003eNiclasen J, Teasdale TW, Andersen AMN, Skovgaard AM, Elberling H, Obel C. Psychometric Properties of the Danish Strength and Difficulties Questionnaire: The SDQ Assessed for More than 70,000 Raters in Four Different Cohorts. PLOS ONE. 2012 Feb 27;7(2):e32025. \u003c/li\u003e\n\u003cli\u003eWorld Health Organization. World mental health report: transforming mental health for all [Internet]. World Health Organization; 2022 Jun [cited 2024 Apr 29]. Available from: https://archive.hshsl.umaryland.edu/handle/10713/20295\u003c/li\u003e\n\u003cli\u003eKusier AO, Folker AP. The Well-Being Index WHO-5: hedonistic foundation and practical limitations. 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Available from: https://www.uvm.dk/-/media/filer/uvm/aktuelt/pdf09/140620-ekspertgruppe-trivselsmaaling.pdf\u003c/li\u003e\n\u003cli\u003eMadsen KR, Ellegaard Ib\u0026aacute;\u0026ntilde;ez Rom\u0026aacute;n J, Trab Damsgaard M, Holstein BE, Kristoffersen MJ, Pagh Pedersen T, et al. Skoleb\u0026oslash;rnsunders\u0026oslash;gelsen 2022. Helbred, trivsel og sundhedsadf\u0026aelig;rd blandt skoleelever i 5., 7., og 9. klasse i Danmark. \u003c/li\u003e\n\u003cli\u003eRoberts C, Freeman J, Samdal O, Schnohr CW, de Looze ME, Nic Gabhainn S, et al. The Health Behaviour in School-aged Children (HBSC) study: methodological developments and current tensions. Int J Public Health. 2009 Sep 1;54(2):140\u0026ndash;50. \u003c/li\u003e\n\u003cli\u003eBosakova L, Madarasova Geckova A, van Dijk JP, Reijneveld SA. School is (not) calling: the associations of gender, family affluence, disruptions in the social context and learning difficulties with school satisfaction among adolescents in Slovakia. Int J Public Health. 2020 Nov 1;65(8):1413\u0026ndash;21. \u003c/li\u003e\n\u003cli\u003eHarel-Fisch Y, Walsh SD, Fogel-Grinvald H, Amitai G, Pickett W, Molcho M, et al. Negative school perceptions and involvement in school bullying: A universal relationship across 40 countries. J Adolesc. 2011 Aug 1;34(4):639\u0026ndash;52. \u003c/li\u003e\n\u003cli\u003eJoyce HD, Early TJ. The impact of school connectedness and teacher support on depressive symptoms in adolescents: A multilevel analysis. Child Youth Serv Rev. 2014 Apr 1;39:101\u0026ndash;7. \u003c/li\u003e\n\u003cli\u003eHolubč\u0026iacute;kov\u0026aacute; J, Kudl\u0026aacute;ček M, \u0026Scaron;irůček J, Madarasov\u0026aacute; Geckov\u0026aacute; A. Test-retest reliability of selected HBSC items measuring problem behaviour among Slovak and Czech adolescents. Cent Eur J Public Health. 2018 Sep 30;26(3):204\u0026ndash;8. \u003c/li\u003e\n\u003cli\u003eGrunspan DZ, Wiggins BL, Goodreau SM. 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Implement Sci. 2022 Oct 29;17(1):75. \u003c/li\u003e\n\u003cli\u003eClarke V, Braun V. Thematic analysis. J Posit Psychol. 2017 May 4;12(3):297\u0026ndash;8. \u003c/li\u003e\n\u003cli\u003eO\u0026rsquo;Cathain A, Hoddinott P, Lewin S, Thomas KJ, Young B, Adamson J, et al. Maximising the impact of qualitative research in feasibility studies for randomised controlled trials: guidance for researchers. Pilot Feasibility Stud. 2015 Sep 7;1(1):32. \u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"pilot-and-feasibility-studies","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pafs","sideBox":"Learn more about [Pilot and Feasibility Studies](http://pilotfeasibilitystudies.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/PAFS/default.aspx","title":"Pilot and Feasibility Studies","twitterHandle":"@MedicalEvidence","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Mental health promotion, schoolchildren, choir singing, class choir, feasibility study, primary school, school well-being, school-based intervention, mixed methods","lastPublishedDoi":"10.21203/rs.3.rs-6030016/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6030016/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground\u003c/p\u003e\n\u003cp\u003eThere is an urgent need for feasible and effective mental health promoting interventions from early childhood. High-quality music education carries the potential to promote school thriving, positive class community and social relations, which are key prerequisites for children’s mental health. However, implementation and potential benefits of this type of intervention have not yet been evaluated in the Nordic countries. The Everyone Can Sing intervention is as a class-based singing intervention that integrates class choir into the regular school schedule two lessons a week for primary school children of age 5-10 years. The lessons follow a manualised pedagogy, which combines co-teaching between the class teacher and an educated choir leader with enactive learning in a safe atmosphere, changing choir partners, musical arousal regulation, a song repertoire including movement and gestures, and choir performances in and outside school. The aim of this feasibility study is twofold: 1) To study feasibility of the implementation of Everyone Can Sing in three Danish primary schools, and 2) to study feasibility of the evaluation design.\u003c/p\u003e\n\u003cp\u003eMethods\u003c/p\u003e\n\u003cp\u003eA non-randomized single-group feasibility trial will be conducted from January 2024 to March 2025 among approximately 900 primary school children in grade 0 to 3 in three Danish public primary school. Six domains relating to feasibility of the intervention (barriers and facilitators of implementation, adaptability, implementation capacity, responsiveness, acceptability and signs of benefit and harms) and three domains relating to feasibility of the study design (validity of questionnaire, uncertainties in data collection and outcome measures) will be assessed. The study follows a mixed methods methodology, involving collection, analyses, and integration of data from baseline and follow-up questionnaires from students, parents and teachers as well as observations of choir and interviews with students, parents, teachers, choir leaders, Everyone Can Sing school coordinators, Everyone Can Sing management and school management at the three schools.\u003c/p\u003e\n\u003cp\u003eDiscussion\u003c/p\u003e\n\u003cp\u003eThe results of this non-randomised feasibility study will inform whether the intervention should proceed to a future, full-size effectiveness trial, return to refinement of the intervention or the evaluation design, or stop.\u003c/p\u003e\n\u003cp\u003eTrial registration: ClinicalTrials.gov, ID: NCT06204029, registered January 2nd, 2024. https://clinicaltrials.gov/study/NCT06204029?cond=NCT06204029\u0026amp;amp;rank=1\u003c/p\u003e","manuscriptTitle":"Everyone Can Sing: Protocol for a non-randomized feasibility study of class choir as mental health promotion among primary school children (ages 6-10) in Denmark","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-22 08:56:47","doi":"10.21203/rs.3.rs-6030016/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Minor revision","date":"2025-09-21T14:51:44+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2025-09-13T05:18:09+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-09-10T18:45:49+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-04T10:04:44+00:00","index":"","fulltext":""},{"type":"submitted","content":"Pilot and Feasibility Studies","date":"2025-02-28T03:05:27+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"pilot-and-feasibility-studies","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pafs","sideBox":"Learn more about [Pilot and Feasibility Studies](http://pilotfeasibilitystudies.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/PAFS/default.aspx","title":"Pilot and Feasibility Studies","twitterHandle":"@MedicalEvidence","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"743a64d8-301b-4697-b80d-c15e5475e1ee","owner":[],"postedDate":"September 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-01-05T16:01:24+00:00","versionOfRecord":{"articleIdentity":"rs-6030016","link":"https://doi.org/10.1186/s40814-025-01757-8","journal":{"identity":"pilot-and-feasibility-studies","isVorOnly":false,"title":"Pilot and Feasibility Studies"},"publishedOn":"2025-12-31 15:58:08","publishedOnDateReadable":"December 31st, 2025"},"versionCreatedAt":"2025-09-22 08:56:47","video":"","vorDoi":"10.1186/s40814-025-01757-8","vorDoiUrl":"https://doi.org/10.1186/s40814-025-01757-8","workflowStages":[]},"version":"v1","identity":"rs-6030016","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6030016","identity":"rs-6030016","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}