This study was conducted to test the feasibility of the intervention, recruitment strategy, and data collection plan for the Screen-Free Time with Friends trial. The current study included 74 children, 92 parents, and 39 local stakeholders from three different school districts from three different municipalities. In addition, 11 afterschool club personnel and three afterschool club leaders were involved in the study. Participants in the study found the project meaningful, with the intervention leading to the implementation of various initiatives in the afterschool club and local community. Additionally, the intervention enhanced collaboration between the school, afterschool club, and local sports associations, fostering a belief that the project had the potential to drive meaningful changes within the local community. However, on the basis of the feasibility criteria (Sørensen et al. 2024), the current study was deemed infeasible due to incomplete implementation of all intervention components by some local communities and schools, as well as less than 85% compliance among parents with the leisure time activity questionnaire, which serves as the primary outcome for the full trial. The insights from this study have informed recommendations for adjustments before scaling up to the full trial (Table 3). The most significant adjustment involves prioritizing parent recruitment and ensuring attendance at family meetings. Furthermore, it is crucial to emphasize the importance of completing the required measurements before the study begins. Given that participants recognized the project’s potential to positively impact their daily lives, we believe the study can be feasible with the adjustments described below.

Regarding implementation of the intervention components, some schools and local communities were unable to complete all components due to lack of time or prioritization. One school did not find the time to complete one of the family meetings and the brief activity during the regular meeting. Parents who attended the family meetings expressed that they liked the meetings; however, they would have preferred greater participation from other parents. Parents not attending the family meetings expressed that they did not attend due to a busy schedule. Therefore, it is important to be aware of the length of the family meetings and the timing during the day. Moreover, it is important to ensure that both teachers and parents find the activities important enough to prioritize spending time on it. This can be achieved through various strategies as outlined in Table 3 and further detailed in the following section.

Importantly, it is essential that the family meeting content is pertinent and engaging for parents and effectively communicated to them, aiming to attract more participants to the family meetings. While stakeholders, who were involved in the initial intervention development, suggested funding dinner for all participants and activities for the children, this idea did not prove effective in practice during implementation. A feasible approach could be to make the task of organizing food and activities for the children a mandatory aspect of project participation, while offering the school’s contact person a guide on how to plan these tasks. Furthermore, it may be essential for some schools to have the option of receiving support from the project team in conducting the activities with the children (Table 3). Furthermore, stakeholders, engaged in the initial intervention development, emphasized that the likelihood of parental attendance at a meeting increase when the content is relevant to their children. In this feasibility study all parents of 3rd or 4th-grade students from each school were invited to the same family meetings. Limiting the group to a single class would likely increase participation, as the meeting would then be more relevant to their specific child (Table 3). Furthermore, there is a need to consider effective strategies or feasible tools for teachers to communicate children’s data and perspectives to parents, thereby enhancing the relevance of the content to parents (Table 3).

All afterschool clubs successfully completed the development program and generally expressed great satisfaction. However, some areas for improvement were identified, and outlined in Table 3, such as assuring sufficient attendance of afterschool club personnel to facilitate professional sparring, which was crucial for both satisfaction with the program and successful development of initiatives. For smaller clubs, collaboration with another club may be a solution. Furthermore, it became apparent that to work most successful, the afterschool club leader should preferably be present and attend actively during the program (Table 3).

The afterschool club leaders and personnel expressed that they want to continue the initiatives developed in the development program if they have the time to prioritize it in a busy daily routine. To increase the likelihood of them continuing the work, alignment of expectations before the start of the development program may be crucial (Table 3). This includes indicating an anticipation of their ongoing commitment, e.g., that they plan meetings scheduled after the completion of the development program. In addition, providing supplementary materials and tools that can be utilized in their subsequent work may prove effective (Table 3).

The local workshops were conducted in two out of three local communities. In the local community in which the workshops were not organized, the local ambassador, who was also the afterschool club leader, may have faced an excessive workload. Besides having two roles in the project, this community was situated in a larger city. A recent report from Denmark showed that citizen’s willingness to participate in activities and tasks in the local community depends on the size of the community. The smaller the community, the greater the participation (Schmidt et al. 2023). This could clarify why engaging local stakeholders in the large city was perceived as a substantial task and, conversely, why the opposite was true in the two other locations. This aspect should be taken into account for the full trial, as providing extra support to the local ambassador in the large cities may be necessary (Table 3). Importantly, to enhance the likelihood of completing this component in all local communities participating in the full trial, it is crucial that the local ambassador does not take on more than one role in the project (Table 3).

The local stakeholders completing the intervention were satisfied with the workshops and their community-broad reach. The actions developed and implemented by the local stakeholders were mainly standalone/individual actions such as events organized by the local sports associations. However, local stakeholders expressed that they wanted to repeat the initiatives developed during the project, thus showing a promising potential for maintenance. From a systemic perspective, even small changes can generate ripple effects throughout the system (Nobles et al. 2022), and thus have the potential to induce system changes. Also, questionnaire responses suggest that the intervention has increased community engagement and networking, establishing the foundation for future collaboration within the community (Hailemariam et al. 2019). Overall, this may strengthen the effects and sustainability of the intervention (Hawe et al. 2009; Skivington et al. 2021).

We failed in recruiting the majority of the children and parents from the included school classes. This became evident during the recruitment process. Consequently, changes were implemented to enhance the method and amount of information provided to the parents, aiming to increase awareness and encourage more parents to register (Table 3). Only a few parents attended the information meeting at the first included school, which was held online. Therefore, the information meeting at the last two schools was held physically at the school. Additionally, it was clear that sending reminders to parents was crucial to ensure their attendance at the information meetings and therefore the frequency of reminders sent to the parents prior to the meeting were increased. In addition, children were informed of the study, and posters were placed at the last school to raise awareness about the project. Despite these adjustments, some parents revealed during the family meetings that they had not enrolled themselves or their child in the project because they were unaware of it.

Parents participating in the study indicated that their primary reasons for registering for the project were finding it meaningful and wanting to contribute to research. This suggests that the limitation in parental recruitment was not attributable to potential parents perceiving the project as irrelevant but rather because they were unaware of the ongoing project. Importantly, parents expressed a concern regarding the required installation of the application, Ethica (Avicienna), to participate in the study. Recognizing this challenge, parents at the last included school were given the opportunity to provide consent for themselves and their child through an online survey tool (SurveyXact) or on paper.

Consequently, for the full trial several adjustments should be considered to increase the recruitment of parents (Table 3). First, awareness of the project must be enhanced at its onset. For that purpose, effective strategies may include seeking support from schoolteachers, boosting the information on the school’s online platform before and after the information meeting, visiting classrooms to inform children, and requesting them to bring a note home for their parents, and enhancing the project’s visibility at the school, such as through the use of posters. In addition, alternative methods for sharing information about the project, such as video materials, must be developed before the full trial. Secondly, making participation contingent on participants installing an application should be avoided or at least thoughtfully considered.

We successfully recruited the required municipalities, schools, afterschool clubs, and local stakeholders, except in one local community where the local workshops did not take place. These stakeholders conveyed their agreement to participate in the project, expressing appreciation for its purpose and meaningfulness. Some stakeholders expressed that they had not received sufficient, consistent, or accurate information about the project, especially concerning the necessary tasks and volume (Table 3). To address this in the full trial, a constructive approach would be to ensure that all stakeholders receive the same information, either by inviting everyone from the school and afterschool club to a single meeting or by distributing the same video material to all involved parties. In addition, the school and the afterschool club should be encouraged to involve relevant staff in the decision whether to participate in the study (e.g., hold an internal meeting). Likely this would allow for common agreement on participation and broader project ownership.

The response rate to the leisure time activities questionnaires answered by parents did not meet the feasibility criteria at baseline. Since parents expressed challenges with the Ethica (Avicenna) application, the distribution method was changed at follow-up and a SMS system and SurveyXact was utilized to send out the questionnaires. We aimed for a higher response rate this way, as the questionnaires were directly delivered to their phones rather than being within an application. To further enhance the response rate, parents were only obligated to complete the leisure time activity questionnaire three times per week for 2 weeks during follow-up, as opposed to the baseline period where they had to respond three times per week for 3 weeks. Despite these adjustments, the response rate declined at follow-up, possibly due to questionnaire fatigue developed during baseline. Therefore, there is a need for further adjustments and feedback from representative end-users before the planned full trial to ensure that the response rate meets the criteria for feasibility (Table 3). One approach to achieve a higher response rate could involve distributing the questionnaire through SMS, as done during follow-up, keeping the questionnaire as concise as possible, and emphasizing the importance of this measurement before parents register for the project.

For the secondary outcome measurements, the feasibility was generally satisfactory with response rates varying from 83–91%, except for the questionnaires distributed to parents and local stakeholders as well as the objective measurement of physical activity. As with the leisure time activities questionnaire, the low response rate for the questionnaire given to parents and local stakeholders could stem from challenges with the Ethica (Avicenna) application and the time required to complete the questionnaire. To enhance response rates for these types of questionnaires, informing participants about the anticipated workload before their agreement to participate is essential (Table 3). Certainly, when utilizing an application for questionnaire distribution, it is vital that the tool is designed to enhance convenience for participants rather than the opposite.

A relatively high percentage of children (10%, 7 out of 70) lost their Axivity AX3 device at follow-up. In this study, we used the attachment method recommended by Petersen et al. (2022), which involves wrapping gauze around the accelerometer to allow air circulation and prevent glue from sticking to the device, minimizing cleaning needs. However, this method may have resulted in insufficient adhesion. To reduce device loss, a modified approach could be adopted by attaching a sticker to enhance adhesion between the adhesive patch and the accelerometer while still minimizing cleaning requirements (Table 3).

One of the strengths of the current feasibility study is that it provides information from three different municipalities and local communities, providing a broad range of perspectives and experiences regarding feasibility. These insights are invaluable for refining the recruitment strategy, intervention components, and assessment methods before undertaking the full randomized controlled trial. As addressed by O’Cathain and colleagues, the feasibility phase of a trial is unique as it often involves continuous adjustments to study protocols and intervention (O’Cathain et al. 2015). In our study, this adaptability was demonstrated through the sequential recruitment of participants and implementation of intervention activities, fostering an iterative approach that enabled us to continually refine our methods and improve the overall feasibility of the study before transitioning to the full trial.

Another strength is that the study included both qualitative and quantitative assessment methods, offering a comprehensive insight into the various aspects related to the feasibility of the study (Glasgow et al. 2019; Skivington et al. 2021). In the current study the quantitative measurements (i.e., surveys and objective measures) were included to test feasibility of the measurement methods (i.e., response rate). In contrast, the collection of qualitative data through interviews, observations and open-ended questionnaires allowed for an exploration of participants’ perspectives and experiences related to the different parts of the study.

Despite the strengths of the current study, it also has several limitations. Importantly, only interviews were conducted with municipality project managers (n = 2), a school representative (n = 1), afterschool club personal (n = 11) and leaders (n = 3), and Ungdomsringen (n = 1). If enough time and resources had been available, it would have been ideal to also conduct interviews with local ambassadors and stakeholders, parents, and school personnel (Sørensen et al. 2024). However, interviews with parents and local stakeholders were replaced with qualitative surveys including open-ended questions. According to Braun et al. (2021), qualitative surveys have the opportunity to produce rich, deep and complex information about participant’s subjective experiences (Braun et al. 2021). In addition, qualitative surveys offer a fairly unique possibility to collect data from multiple individuals, providing the potential to capture a diversity of perspectives and experiences (Braun et al. 2021). Furthermore, respondents may find it easier to be honest and provide critical feedback in an open-ended survey compared to interviews, as they are not engaging with the research team face-to-face. In the current study, the answers from the open-ended items were diverse and included both positive and negative feedback. With this in mind, changing from interviews to questionnaires should not pose significant limitations to the study. However, interviews may provide other opportunities, including the ability to ask follow-up questions based on the responses. Moreover, there is no guarantee that everyone is willing to provide detailed responses in writing, as it can be time-consuming. In this context, we observed that parents tend to avoid elaborating on open-ended questions.

Despite our efforts to ensure diversity in sampling across communities, we were unable to recruit the majority of children and parents from the selected 3rd and 4th grade school classes. However, given that this is a feasibility trial with a limited number of participants, achieving complete diversity was unlikely. As such, the findings should be interpreted with the understanding that the data may reflect a subset of the target population, which could limit the generalizability of the results. Nevertheless, the included children are representative when compared to a background population from the PHASAR database including 732 children (Pedersen et al. 2018). In addition, few parents (n = 8–20) and local stakeholders (n = 9) answered the questionnaires about knowledge and engagement at both baseline and follow-up, and therefore it was not possible to get a clear understanding of whether behavioral determinants had changed. In any case, this study was not designed to test modifications in behavioral outcomes but solely to evaluate the feasibility of various study components. The full trial will be conducted as a cluster-randomized controlled trial, including a larger sample size of 18 schools, a control group, and an extended intervention period. Consequently, it will be designed to evaluate the effectiveness of the intervention on behavioral outcomes.