In the context of a viral outbreak and of widespread quarantine measures, a significant increase in psychological disorders, such as stress or fear behaviours, had previously been observed. This distress has been described on adults, but no data have been collected yet for paediatric populations.

After a traumatic event, children and adolescents may present several clinical consequences, the most common being Post-Traumatic Stress Disorder (PTSD). Moreover, PTSD in children and adolescents is often associated with comorbid disorders, such Attention Deficit Hyperactivity Disorder, depression, attachment and anxiety disorders, sleep disturbances and behavior problems.

The aim of this study is to present the methodology of "CoCo 20" : is to assess the impact of the pandemic of coronavirus disease 2019 (Covid-19) and of seclusion measures on mental health and on the development of psychological disorders in children in the short to medium term

In the context of a viral outbreak and of widespread quarantine measures, a significant increase in psychological disorders, such as stress or fear behaviours, had previously been observed. This distress has been described on adults, but no data have been collected yet for paediatric populations.

After a traumatic event, children and adolescents may present several clinical consequences, the most common being Post-Traumatic Stress Disorder (PTSD). Moreover, PTSD in children and adolescents is often associated with comorbid disorders, such Attention Deficit Hyperactivity Disorder, depression, attachment and anxiety disorders, sleep disturbances and behavior problems.

The aim of this study is to present the methodology of "CoCo 20" : is to assess the impact of the pandemic of coronavirus disease (Covid-19) and of seclusion measures on mental health and on the development of psychological disorders in children in the short to medium term.

The major inclusion criteria are children and adolescents under 18 years of age who have been affected by the Covid 19 pandemic. Three groups were defined: children in group one had a previous history of traumatic events, those in group two had a record of previous psychiatric or psychological disorder with a follow-up treatment and Group three included children without traumatic history nor psychiatric or psychological follow-up treatment. Participants will be assessed at baseline (V0), 1 week after (V1), one month after baseline (V2), one week after the end of the containment (V3) and one month after the end of the containment (V4).

Main analyses comprise analyses of variance and regression analyses of predictors of clinical evolution over time

Inclusion Criteria:

• Children affected by the Coronavirus disease 2019 (Covid-19) pandemic;
• Age between 0 and under 18 at the time of inclusion;
• Affiliated with a social security scheme;
• Having a good command of the French language (French);
• Children whose parents have accepted participation in the study (collection of informed consents).

Exclusion Criteria:

• Children and/or young adults with a psychotic disorder or autism spectrum disorder;
• Children and/or young adults with an average intellectual disability (< to 50);
• Person deprived of liberty by judicial or administrative decision1;
• Person subject to a period of exclusion for another search.

Group 1 (PTSD): children with an identified traumatic history; Group 2 (Pathology): children with psychological follow-up treatment for a psychiatric disorder, without traumatic history; Group 3 (Control): children without traumatic experience and without psychiatric or psychological follow-up treatment.