COVID-19 outbreak caused severe disruptions in daily life, partly due to limitations implemented to prevent the spreading. In France, it included school closures during a national lockdown, then a reopening of schools, with access depending on viral status of students and teachers. Those changes had an impact on children's mental health. We conducted an online cross-sectional study using a parental self-administered survey in December 2021 to explore the emotional and behavioral changes (EBC) during this 5th wave (W5) and retrospectively since the first one (W1) in their children and their multidimensionality with principal factor analysis (PCA) and stability analysis. Out of 4552 parent responders, 62.4% (n = 2839) noticed negative EBC during W1 and 54.1% (n = 2462) during W5 of the pandemic. Only 10.0% of the responders noticed negative EBC at W1 but not during the W5. In younger children (3-6 years old) with significant EBC, PCA revealed three main dimensions at W1 and W5: restlessness, depression and anxiety. In older children (7-13 years old), PCA showed partially similar dimensions: depression-suicidality, anxiety and withdrawal. Almost all correlations between dimensions at W1 and W5 were significantly positive. Every EBC was stable across waves, except for one. Recall bias concerning the EBC during W1 and lack of data concerning parental mental health should be taken into account. Our stability analysis found a strong correlation between dimensions at W1 and W5. Our results highlighted the impact of the COVID-19 outbreak on children's mental health and the predictive aspect of its early deterioration.
© 2023. The Author(s).