Abstract

Few multinational studies have assessed risk factors and coping strategies associated with the impact of the COVID-19 pandemic on children’s mental health over time. The Collaborative Outcomes study on Health and Functioning during Infection Times (COH-FIT) is the largest transcontinental, multi-wave, cross-sectional survey collecting multi-nation data on well-being and psychopathology during the pandemic. We analyzed country-specific, general-population-based, representative COH-FIT data of 6067 children aged 6–13 years from 12 countries across repeated cross-sectional waves over a period of >2 years (Apr/2020–May/2022), addressing through current and retrospective assessment pre- to intra-pandemic changes in well-being (WHO-5) and general psychopathology scores (Pc) (0–100) in relation to COVID-related deaths, stringency index, eight a priori risk factors, and 16 coping strategies in different responders at each wave. From pre- to intra-pandemic, WHO-5 scores decreased (−4.59, 95 %CI=−6.18 to −2.99, p < 0.001), while PC-scores increased (+6.68, 95 %CI=4.48–8.88, p < 0.001) significantly, following distinct time patterns but both returning to near pre-pandemic levels. Changes in both scores varied by country. WHO-5 scores correlated strongly with PC and subdomain scores. Both score changes were significantly but minimally associated to COVID-19 deaths/stringency index. The proportion of children screening positive for depression increased from 3.9 % to 8.3 % (χ²=145.70, p < 0.001) and for major depression from 0.6 % to 2.2 % (χ²=68.64, p < 0.001) intrapandemic. WHO-5 and PC-score changes were significantly associated with female gender, school closure, and pre-existing physical and mental conditions, with cumulative effects. The five most frequently endorsed coping strategies were family contact (85.2 %), friends (67.3 %), outdoor play (54.0 %), pet interaction (51.5 %), and internet use (50.9 %). Identified risk groups and coping strategies can inform targeted interventions and global public health policy.

1. Introduction

The Coronavirus Disease 2019 (COVID-19) pandemic emerged as a global crisis with unprecedented ramifications transcending geographical, cultural, and socioeconomic boundaries (Fauci et al., 2020). Apart from its public-health-related toll, the related restrictive measures posed immense challenges to every personal, societal, economical and professional aspect of life worldwide, especially in certain risk subgroups (GBD Demographics Collaborators, 2024). Children represent a particularly vulnerable societal group that requires special consideration (Singh et al., 2020), due to several age-specific biological and psychosocial risk factors. Children are particularly vulnerable to neurodevelopmental disruption due to the combination of a heightened biological plasticity and altered stress-response system reactivity during this critical developmental phase (Agorastos et al., 2019, 2018) together with increased exposure to subjective stress, dependency on social interactions, familial stressors (e.g., higher parental stress among preschoolers), undiagnosed neurodiversity concerns, restricted access to social and educational activities or entertainment, and limited coping abilities (Loades et al., 2020; Marques de Miranda et al., 2020; Samji et al., 2022; Tso et al., 2022), as well as specific pandemic-related stressors, such as social and physical activity disruptions, reduced access to supportive services, and unsupervised use of electronic media. Moreover, over 50 % of those with a mental disorder develop it by age 18 (Solmi et al., 2022c).

Since the beginning of the pandemic, a growing body of high-quality, cohort-based research has examined its impact on children’s mental health. Recent meta-analytic evidence suggests a moderate detrimental pandemic influence on mental health of children around the world, with higher prevalences of emotional and behavioral problems than pre-pandemic (Dragioti et al., 2022; Jing et al., 2024; Miao et al., 2023), especially in children of specific risk groups [e.g., pre-existing somatic conditions (Vasquez et al., 2020) and mental health problems (Cortese et al., 2020)]. A large meta-analysis of 53 longitudinal cohort studies from 12 countries including 40,807 children and adolescents identified additional risk factors, including female gender, low income-class and lower socioeconomic country of residence (Madigan et al., 2023). Families with children at risk struggled even harder to cope with pandemic-related restrictions on top of additional child-related obstacles affecting daily routines (e.g., home schooling) (Becker et al., 2020).

However, mental health studies in children often resulted in mixed or even contradictory findings, due to high cross-study heterogeneity of study design, setting, outcomes, assessment tools, timing, geographical and cultural factors (Dragioti et al., 2022). Most studies have important limitations, such as a focus on isolated psychopathology domains, small sample sizes, data collection restricted to one country/language or population subgroup, combined reporting of children/adolescents as well as non-representative sampling (Dragioti et al., 2022). Moreover, most studies are either cross-sectional, single time-point studies or longitudinal studies that did not account for variation in COVID-related parameters (e.g., death rates, restrictive measures) over time. These facts limit the generalizability of many findings, posing methodological barriers to the synthesis of current evidence. Although the large meta-analysis of Madigan et al. offers some comparison and evidence on international variations in psychopathology in children and adolescents (Madigan et al., 2023), no individual study has offered simultaneous transcontinental assessments. Finally, most studies focused on psychopathology only, neglecting the important area of helpful coping strategies.

The “Collaborative Outcomes study on Health and Functioning during Infection Times” (COH-FIT) is the largest international, multilanguage (30 languages) online study worldwide measuring the impact of COVID-19 pandemic on health and functioning in representative and weighted, convenience samples of adults, adolescents, and children across 5 continents over a period of >2 years, cross-sectionally assessing different responders in different waves (Solmi et al., 2022a, b). Leveraging current, intra-pandemic and retrospective, pre-pandemic COH-FIT data of minors, this report aims to provide comprehensive transcontinental insights into mental health trajectories amidst the evolving pandemic landscape in children. COH-FIT results on adults (Solmi et al., 2024a, 2024c) and adolescents (Solmi et al., 2024b) have been previously published, as well as the validation of both a composite psychopathology P-score and the multi-language translation (Solmi et al., 2023). In this article, we report nationally representative global and country-related findings on pre- to intra-pandemic changes in well-being and overall psychopathology in children over a period of >2 years, hypothesizing worsened well-being and increased psychopathology globally, enhanced impairment in vulnerable subgroups with cumulative effects across multiple risk factors, and a negative relationship to current death rates and stringency measures over time. We also report on the subjectively endorsed coping strategies for dealing with the pandemic.

2. Experimental procedures

2.1. Study design

The COH-FIT design has been described in detail previously (Solmi et al., 2022a, b). This article presents an analysis of COH-FIT Children (COH-FIT-C) data in association to COVID-related deaths, stringency measures and several other related factors, from a large, transcontinental, representative child sample (age: 6–13 years) collected over a period of >2 years from 12 different countries (Table 1). Nationally representative data were collected cross-sectionally through polling institutes at distinct wave periods, including different participants at each wave (Suppl. Methods). Each child participated at one time point, but reported through current and retrospective assessment on intra- and pre-pandemic well-being and other data, enabling reconstruction of pre- vs. intra-pandemic differences.