COVID-19 school and kindergarten closure relates to children's social relationships: a longitudinal study in Japan

The worldwide spread of the novel coronavirus, SARS-CoV-2, has considerably affected our everyday lives. Although children accounted for only a small proportion of the infected population and they likely showed less severe symptoms compared to adults^1–3, children seem to be vulnerable to sudden changes in their physical and social environment: their health-related behaviors such as physical activities, sleep patterns, eating habits, and psychological responses have been negatively influenced by the pandemic^4,5. A major change in children’s social life might be that, as the result of kindergarten and/or school closure, children had to be confined at home for a certain period in many countries, including Japan, to prevent the virus from rapidly spreading. This school closure has impacted the learning environment of students all over the world⁶. More importantly, it could have influenced children’s social development^7–9. Nevertheless, although studies have examined children’s mental health, it is not well known how school and kindergarten closure owing to the pandemic affects social relationships between children and others, such as parents and friends.

The change in social relationships between children and family or non-family members (e.g., peers) may be a crucial factor when we consider the mechanism of the negative impact of school closure on children's social development. Generally, children’s social relationships expand from family members to others as they grow and develop. Parent–child relationships are assumed to provide a fundamental basis for the development of social interactions with others, such as relationships with peers^10–12. Relationships with friends also influence children’s social and emotional development¹³, such that the quality of friendship predicts improvements in school attitudes¹⁴. School closure and home confinement caused by the pandemic directly affected children’s face-to-face contact with others in social settings, which may have affected their social relationships. For instance, school closure and limited outdoor activities likely deprived children of opportunities to interact with peers, while home confinement may have enhanced parents’ role in enabling healthy lives for their children¹⁵.

Children’s social behavior in everyday contexts has often been assessed using the Strength and Difficulties Questionnaire (SDQ)^16,17. This questionnaire consists of five subcategories, including the components of peer problems and prosocial behavior. The SDQ is usually filled out by parents or teachers. The characteristics of the SDQ have enabled researchers to investigate the impact of the COVID-19 pandemic on children’s social relationships through an online survey^18–20. Previous studies using the SDQ have shown that children had higher socio-emotional problems during the COVID-19 pandemic to those before in countries with a national lock down, such as UK and Lithuania^21,22. For example, an UK study reported that children’s socio-emotional problems increased during the pandemic compared to before the pandemic, and the tendency was stronger children compared to adolecents²¹. The changes in socio-emotional problems may be due to the national lockdown, because changes in the socio-emotional problems were related to the timing of the national lockdown. However, the results may not be applied to children in other countries without a national lockdown, such as Japan. For instance, Moriguchi et al.¹⁹ conducted a cross-sectional study on Japanese parents, whose children were aged 4–9 years, to investigate if and how children’s social behaviors before and during the pandemic-led school closure. They found that children experienced more problems in their peer relationships during the outbreak of the disease and, on the contrary, they showed more prosocial behavior during the same period. However, few studies have applied longitudinal methodologies that can sequentially detect the effect of school closures on social behaviors in the same groups of children in countries without lockdown. This limits the possibility of establishing relationships between school closures and children’s social development. Although few longitudinal studies were conducted in Japan, previous studies in the wake of past calamities such as the Great East Japan Earthquake, tsunami, and radiation disaster have reported that Japanese children exhibited problems in social behaviors and social relationships^23,24. Specifically, children who suffered through the natural disaster (e.g., ones who had been moved to other cities) had problems in both peer relationship and prosocial behaviors as compared to those children who had not been influenced by the disaster. Although the COVID-19 pandemic is different from a natural disaster, there would be some similarities in terms of the lack of social relationship with peers.

Additionally, compared to children’s peer relationships, which can be explored by the SDQ, their social relationships with parents have been much less explored. Investigation of parent–child relationships during the pandemic is important since school closure and home confinement would have led to an increase in the time that children spent with their parents. Specifically, increased prosocial behavior in children¹⁹ could have been attributed to changes in their perceived closeness towards parents, induced by the increase in parent–child interaction time. Psychological literature has shown that people become more prosocial toward those with whom they perceive more mental proximity^25,26.

Therefore, the current study investigated the impact of social quarantine on children’s social relationships using longitudinal data collected during (T1) and after (T2) intensive school closure and home confinement brought about by the COVID-19 pandemic. In addition, as a follow-up survey, we collected the data from part of the same participants approximately 4 months later the second data collection (T3). This period was when the Japanese government declared a state of emergency as in the first data collection period, but schools and kindergartens remained open. Thus, children did not experience intensive home confinement. It was postulated that the data collected during the period of school closure reflected the impact of the pandemic on children’s social relationships. Meanwhile, it was pertinent to ask whether children's social relationships changed or remained the same once schools reopened. Specifically, this study had two primary objectives: (1) to provide longitudinal data using the SDQ, which were lacking in previous studies, to examine this impact more directly; and (2) to explore how changes in children’s social relationships differed between parents and others (e.g., peers). To meet the latter objective, this study used the Inclusion of Other in the Self (IOS) Scale^27,28 to measure children’s perceived self-parent and self-other boundary overlap. It was hypothesized that (1) for infants and preschoolers, social quarantine would not have influenced social relationships with others, since parents are the dominant others for children during these periods for interaction, regardless of home confinement, and (2) for elementary schoolers, social quarantine would have affected children’s social relationships with others since the dominance of association with parents weakens while that with others, such as peers, strengthens. Thus, it was posited that the effects of school closure and home confinement may vary among infancy, preschool age, and school age. Additionally, leveraging the characteristics of the longitudinal data, this study examined whether children’s social relationships with peers changed after school closure, while children showed both more problems in their peer relationships and more prosocial behavior during such closure compared with before¹⁹. Supplementarily, this study also explored the changes in children’s social environment during and after intense home confinement.

The primary purpose of this study was to investigate changes in children’s social relationships during and after quarantine using the SDQ and the IOS. Previous studies have shown that children’s and adolescents’ physical and mental health-related behaviors, such as physical activities, can be affected by sudden changes in their physical and social environment during the COVID-19 pandemic^4,5. Kindergarten/school closure and the lack of interaction with peers may affect physical activities in children³⁵. However, few studies examined the impact of quarantine on children’s social relationships with others.

Using the SDQ measure, our longitudinal data revealed that quarantine was not related to children’s social behavior for all age groups. These results can be interpreted with two possible explanations. First, although school closure may have influenced children’s social relationships, it was not severe enough to change children’s behavior towards others. Second, the present study might have failed to detect changes in children’s social behavior due to methodological factors, as parental report measures could provide only coarse data and were more likely to overlook children’s problems than detailed measures³⁶. It is also plausible that parents were unable to grasp children’s behavioral change precisely because during home confinement, it was relatively difficult to observe children’s interaction with peers. Although it is acknowledged that a sophisticated follow-up study is necessary, the findings drawn from this longitudinal data would be rather plausible and convincing as these previous studies used only cross-sectional data. Besides, it may also be the case that children could socially interact with peers even during home confinement, which led to fewer changes in their social behavior, given that children spent more time playing outside and using screens at T1 compared with T2. This may be due to that the national lock down was not introduced in Japan in contrast with other countries, where children had higher socio-emotional problems during the pandemic compared to before^21,22. Such changes in their social lives may have compensated for the quantity and quality of social relationships that can be maintained in formal schooling. However, the amount of time when they did not go to school was considerably huge (several days per week), while the increased time of playing outside and using screens was still less (several hours per week). Hence, children’s social lives must have been affected by daycare, kindergarten, and school closure at least to some extent.

Using the IOS measure, elementary school children’s perceived proximity to parents was found to have significantly decreased from during to after school closure (i.e. between T1 and T2), while that to others, such as peers, showed the opposite pattern. These results suggest that, as posited, the pandemic-led school closure and home confinement may have been related to the psychological distance that children at school age felt toward others. Entry into formal schooling largely affects children’s peer experiences³⁷, and children spend more time with their classmates (and teachers) during the day than their family members. School closure directly transformed their usual style of social contact, which would have led to changes in their feelings toward others. Meanwhile, once schools reopened, children’s perceived mental closeness seemed to have recovered to some extent, although this is not conclusive because this study does not have data on the same participants’ IOS scores before the pandemic. If this was the case, perceived social relationships during middle childhood would be subject to not only vulnerability but also a certain amount of resilience. The results from the follow-up survey support this possibility to some extent as the IOS scores did not differ between after quarantine and 6 months after the reopening of kindergartens and schools (i.e., T2 to T3). Thus, it would be plausible to think that kindergarten/school closure significantly influenced the way children perceived closeness to others, rather than to think that tense critical situations such as the declaration of a state of emergency itself affected it.

Unlike school-age children, this study did not find significant changes in infants’ and preschoolers’ perceived closeness to both parents and others, although the overall trends were similar to those of older participants. Compatible with the study’s prediction, social quarantine was less related to these children’s social relationships. Parent–child interactions play an important role in children’s social development^10–12; hence, for younger children, it is likely that perceived proximity remains somewhat robust, as long as there are no circumstances that would significantly alter ways of parent–child relationships (e.g., parent–child permanent separation). Meanwhile, when family coexistence was challenged during quarantine, problems pertaining to children became more serious⁸.

The present study has theoretical and practical implications for children’s social development. Theoretically, our results showed that changes in the social environment can affect children’s social relationships measured by IOS. However, the Japanese children's social behaviors measured by SDQ were not related to the kindergarten and school closure led by COVID-19 pandemic, which is inconsistent with the previous studies about children’s socio-emoitonal behaviors in countries with the national lock down^21,22. Taken together, the strict lockdown, but not school closure, can affect children’s social behaviors, perhaps because parents may have felt strong stress under the national lockdown, which may lead to children’s social behaviors. Moreover, our results were also inconsitent the Great East Japan Earthquake, tsunami, and radiation disaster^23,24. The inconsistency may be because the earthquake could have been more stressful than COVID-19 pandemic for children. Children under the earthquake may have experienced the loss of their family or friends. Such stressful events can have stronger impacts on children’s social behaviors. Practically, at least from the results of this study, it could be said that parents do not have to seriously worry about children’s social development in terms of intense quarantine. However, previous studies showed that parents’ mental problems can affect children’s mental health during the COVID-19 pandemic³⁸. Moreover, it is possible that children in an adverse situation (e.g., low-socioeconomic status family) may have suffered more problems than other children during the COVID-19 pandemic. We need to examine the issues in future studies.

This study has several limitations. First, the exact perceived proximity to peers is unclear since the question was asked in reference to non-family members, with peers raised just as an example. Second, it is possible that the data collected in this study were biased or distorted because parents, instead of children, answered the questionnaire indirectly. Specifically, the IOS is generally used to evaluate participants’ own psychological closeness to others and parental report based on their observations on their children’s behavior is not the conventional way of using IOS^27,28. We adopted parents as informers because our target participants included infants. In future studies, we need to devise a methodology, such as observing infants’ and children’s own behaviors online, to evaluate their psychological closeness to others. Additionally, our data might have been possibly biased as we collected the data via a handy resource of an online survey. Third, although only limited effects of quarantine were found on children’s social relationships, the extent to which the findings can be generalized to other countries is not clear. The characteristics of quarantine may have differed across countries. When faced with the COVID-19 pandemic, several countries such as China, UK, India, Spain, and others imposed strict lockdown, but in Japan, activity restrictions were imposed in the form of self-restraints rather than a lockdown. In other words, Japanese people had more mobility and freedom compared to people in other countries where people’s actions were strictly regulated. Thus, our results may not be generalized to children in different situations. Fourth, the effect of non-face-to-face communication (e.g., online live interactions) was only partially explored. Even during intensive quarantine, children’s perceived proximity to others may have been improved by enhancing online live interactions with peers. These limitations should be addressed in future studies. Nevertheless, the current study could contribute to a better understanding of how physical and social quarantine from others affects children’s social bonding and could possibly inform better policy-making.

In middle childhood, when peer relationships are intimately formed, quarantine is a factor that psychologically distanced children from others. Although the present study did not observe the actual differences in children’s social behavior during and after quarantine, using the IOS measure it was detected that children’s social development can potentially be altered. Hence, the change in children’s perceived proximity to others can negatively influence children’s social development and well-being, even if not serious enough to increase problematic behavior. Measures that enable children to feel closer to others are necessary (e.g., online environment, safe in-person meeting) to enable or even promote children’s healthy development during this difficult time.