# Life satisfaction in the context of the COVID-19 pandemic among middle school adolescents in France: findings from a repeated cross-sectional survey
(EnCLASS, 2012–2021)

Cynthia Hurel, Virginie Ehlinger, Michal Molcho, Jérémie F. Cohen, Bruno Falissard, Mariane Sentenac, Emmanuelle Godeau

► To cite this version:

Cynthia Hurel, Virginie Ehlinger, Michal Molcho, Jérémie F. Cohen, Bruno Falissard, et al.. Life satisfaction in the context of the COVID-19 pandemic among middle school adolescents in France: findings from a repeated cross-sectional survey (EnCLASS, 2012–2021). Frontiers in Pediatrics, 2023, 11, pp.1204171. 10.3389/fped.2023.1204171 . hal-04194852

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# Life satisfaction in the context of the COVID-19 pandemic among middle school adolescents in France: findings from a repeated cross-sectional survey
(EnCLASS, 2012–2021)

Cynthia Hurel, Michal Molcho, Jérémie F. Cohen, Bruno Falissard, Mariane Sentenac, Emmanuelle Godeau, Virginie Ehlinger

► To cite this version:

Cynthia Hurel, Michal Molcho, Jérémie F. Cohen, Bruno Falissard, Mariane Sentenac, et al. Life satisfaction in the context of the COVID-19 pandemic among middle school adolescents in France: findings from a repeated cross-sectional survey (EnCLASS, 2012–2021). Frontiers in Pediatrics, 2023, 11, pp.1204171. 10.3389/fped.2023.1204171. hal-04194852

HAL Id: hal-04194852

https://hal.science/hal-04194852v1

Submitted on 7 Jun 2024

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons Attribution 4.0 International License
<figure><img src="image_2.png" /></figure>

Check for updates

OPEN ACCESS

EDITED BY
Henrique Barros,
University of Porto, Portugal

REVIEWED BY
Zorica Momcilo Zivkovic,
University Hospital Center Dr Dragiša Mišović,
Serbia
Rossella Gaudino,
University Hospital of Verona, Italy

*CORRESPONDENCE
Emmanuelle Godeau
emmanuelle.godeau@ehesp.fr

RECEIVED 12 April 2023

ACCEPTED 07 July 2023

PUBLISHED 08 August 2023

CITATION

Hurel C, Ehlinger V, Molcho M, Cohen JF, Falissard B, Sentenac M and Godeau E (2023) Life satisfaction in the context of the COVID-19 pandemic among middle school adolescents in France: findings from a repeated cross-sectional survey (EnCLASS, 2012–2021). *Front. Pediatr.* 11:1204171.
doi: 10.3389/fped.2023.1204171

COPYRIGHT

© 2023 Hurel, Ehlinger, Molcho, Cohen, Falissard, Sentenac and Godeau. This is an open-access article distributed under the terms of the [Creative Commons Attribution License (CC BY)](https://creativecommons.org/licenses/by/4.0/). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

# Life satisfaction in the context of the COVID-19 pandemic among middle school adolescents in France: findings from a repeated cross-sectional survey (EnCLASS, 2012–2021)

Cynthia Hurel¹,², Virginie Ehlinger³, Michal Molcho⁴, Jérémie F. Cohen⁵,⁶, Bruno Falissard⁷,⁸, Mariane Sentenac⁶ and Emmanuelle Godeau¹,³*

¹Department of Human and Social Sciences, EHESP School of Public Health, Rennes, France, ²Rennes University, Centre Hospitalier Universitaire (CHU) de Rennes, Department of Epidemiology and Public Health, Rennes, France, ³UMR 1295 CERPOP, Inserm, Université Toulouse III - Paul Sabatier, Team SPHERE, Toulouse, France, ⁴Department of Children's Studies, School of Education, University of Galway, Galway, Ireland, ⁵Department of General Pediatrics and Pediatric Infectious Diseases, Hôpital Necker-Enfants malades, AP-HP, Université Paris Cité, Paris, France, ⁶Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team, EPOPé, Paris, France, ⁷Paris-Saclay University, UVSQ, CESP, Inserm U1018, Paris, France, ⁸Public Health and Epidemiology Department, AP-HP, Hôpital du Kremlin Bicêtre, Le Kremlin Bicêtre, France

**Background and aims:** Since the COVID-19 pandemic, several studies have reported a decrease in adolescents' well-being. We aim to describe life satisfaction over the last decade and examine the factors associated with its variations between 2020 and 2021 among French students in their last year of middle school (around 14–15 years old).

**Methods:** Data were drawn from a repeated biennial cross-sectional national survey conducted in French schools over the last decade (EnCLASS study), using a self-administered questionnaire. After describing life satisfaction trends between 2012 and 2021 using the Cantril ladder, we examined individual changes in life satisfaction between 2020 and 2021 and their associations with housing and studying conditions during the COVID-19 lockdown, using multinomial logistic regression analysis (decrease, increase, no change as reference).

**Results:** Among the 17,686 survey respondents, an overall slight decrease in the prevalence of adolescents reporting high life satisfaction (i.e., Cantril score ≥6) was observed since 2012 with the lowest proportion reported in 2021 (77.4%). Between 2020 and 2021, 16.3% of French adolescents experienced an improvement in life satisfaction, while 17.7% experienced the opposite. Decrease in life satisfaction between 2020 and 2021 was more likely experienced by adolescents living in reconstructed families [aOR 2.09 (95%CI, 1.58–2.77)], those who did not have their own room [aOR 1.58 (1.16–2.15)], nor access to the Internet to interact with their friends during the lockdown [aOR 1.47 (1.09–1.98)]. Interestingly, more girls than boys were represented in both those reporting increase and decrease in life satisfaction [aOR 1.82 (1.40–2.37) and 1.43 (1.14–1.79)], respectively].
<figure><img src="image_2.png" /></figure>

Check for updates

OPEN ACCESS

EDITED BY
Henrique Barros,
University of Porto, Portugal

REVIEWED BY
Zorica Momcilo Zivkovic,
University Hospital Center Dr Dragiša Mišović,
Serbia
Rossella Gaudino,
University Hospital of Verona, Italy

*CORRESPONDENCE
Emmanuelle Godeau
emmanuelle.godeau@ehesp.fr

RECEIVED 12 April 2023

ACCEPTED 07 July 2023

PUBLISHED 08 August 2023

CITATION

Hurel C, Ehlinger V, Molcho M, Cohen JF, Falissard B, Sentenac M and Godeau E (2023) Life satisfaction in the context of the COVID-19 pandemic among middle school adolescents in France: findings from a repeated cross-sectional survey (EnCLASS, 2012–2021). *Front. Pediatr.* 11:1204171.
doi: 10.3389/fped.2023.1204171

COPYRIGHT

© 2023 Hurel, Ehlinger, Molcho, Cohen, Falissard, Sentenac and Godeau. This is an open-access article distributed under the terms of the [Creative Commons Attribution License (CC BY)](https://creativecommons.org/licenses/by/4.0/). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

# Life satisfaction in the context of the COVID-19 pandemic among middle school adolescents in France: findings from a repeated cross-sectional survey (EnCLASS, 2012–2021)

Cynthia Hurel<fnref n="1" />,², Virginie Ehlinger³, Michal Molcho⁴, Jérémie F. Cohen⁵,⁶, Bruno Falissard⁷,⁸, Mariane Sentenac⁶ and Emmanuelle Godeau<fnref n="1" />,³*

**Background and aims:** Since the COVID-19 pandemic, several studies have reported a decrease in adolescents' well-being. We aim to describe life satisfaction over the last decade and examine the factors associated with its variations between 2020 and 2021 among French students in their last year of middle school (around 14–15 years old).

**Methods:** Data were drawn from a repeated biennial cross-sectional national survey conducted in French schools over the last decade (EnCLASS study), using a self-administered questionnaire. After describing life satisfaction trends between 2012 and 2021 using the Cantril ladder, we examined individual changes in life satisfaction between 2020 and 2021 and their associations with housing and studying conditions during the COVID-19 lockdown, using multinomial logistic regression analysis (decrease, increase, no change as reference).

**Results:** Among the 17,686 survey respondents, an overall slight decrease in the prevalence of adolescents reporting high life satisfaction (i.e., Cantril score ≥6) was observed since 2012 with the lowest proportion reported in 2021 (77.4%). Between 2020 and 2021, 16.3% of French adolescents experienced an improvement in life satisfaction, while 17.7% experienced the opposite. Decrease in life satisfaction between 2020 and 2021 was more likely experienced by adolescents living in reconstructed families [aOR 2.09 (95%CI, 1.58–2.77)], those who did not have their own room [aOR 1.58 (1.16–2.15)], nor access to the Internet to interact with their friends during the lockdown [aOR 1.47 (1.09–1.98)]. Interestingly, more girls than boys were represented in both those reporting increase and decrease in life satisfaction [aOR 1.82 (1.40–2.37) and 1.43 (1.14–1.79)], respectively].

<footnote n="1">¹Department of Human and Social Sciences, EHESP School of Public Health, Rennes, France, ²Rennes University, Centre Hospitalier Universitaire (CHU) de Rennes, Department of Epidemiology and Public Health, Rennes, France, ³UMR 1295 CERPOP, Inserm, Université Toulouse III - Paul Sabatier, Team SPHERE, Toulouse, France, ⁴Department of Children's Studies, School of Education, University of Galway, Galway, Ireland, ⁵Department of General Pediatrics and Pediatric Infectious Diseases, Hôpital Necker-Enfants malades, AP-HP, Université Paris Cité, Paris, France, ⁶Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team, EPOPé, Paris, France, ⁷Paris-Saclay University, UVSQ, CESP, Inserm U1018, Paris, France, ⁸Public Health and Epidemiology Department, AP-HP, Hôpital du Kremlin Bicêtre, Le Kremlin Bicêtre, France</footnote>
**Conclusions:** This study shows that the way adolescents experienced the first 2020 lockdown in France was not uniform, and that one must consider sex as well as housing and studying conditions when interpreting adolescents' life satisfaction decrease during the COVID-19 pandemic.

KEYWORDS

life satisfaction, adolescents', COVID-19, well-being, mental health, cross-sectional study, school survey

# 1. Introduction

Many studies conducted since 2020 have suggested that the COVID-19 pandemic and its mitigation measures have had numerous psychosocial consequences, including on adolescents' well-being. More specifically, several studies found a decrease in adolescents' quality of life and life satisfaction, and an increase in the incidence of mental health disorders such as anxiety, depressive syndrome, psychosomatic complaints, and suicidal ideation (1-5). Authors identified protective and risk factors of well-being, associated with sociodemographic characteristics, social and family environment, physical environment, and lifestyle. Those findings on adolescents' well-being have been confirmed in France by the Confeado study, which aimed to understand how children and adolescents aged 9-16 years experienced the first lockdown in France (between March and May 2020), and how it may have affected their well-being (6). With 3,898 children and adolescents included, the Confeado study found that better living conditions during lockdown were associated with higher resilience scores. However, few studies have been able to contextualize the impact of the pandemic (and its mitigation measures) on adolescents' well-being and measure it over time (7).

Life satisfaction is a term related to subjective well-being and can be used to summarize how people perceive their life (8). It can be measured by the Cantril ladder, a one-item validated scale that is easy to understand and quick to answer, including by adolescents (8, 9). Life satisfaction among adolescents or young adults seems strongly correlated to life experience and mental health, especially the positive aspects of mental health (8, 10).

Based on data collected from adolescents periodically, the study EnCLASS is a unique opportunity to analyze data over the past decade to identify time trends in life satisfaction before and during the COVID-19 pandemic. Taking those trends into consideration, we further assessed associations between individual changes in life satisfaction among students in their last year of middle school (around 14-15 years) between 2020 and 2021 and housing and studying conditions during the COVID-19 lockdown experimented in March 2020 (measured retrospectively).

# 2. Materials and methods

## 2.1. Study design and sample

Our study used the data collected for the French national survey in middle- and high-school among adolescents on health and substances

(EnCLASS). EnCLASS is a repeated biennial cross-sectional survey conducted in schools in France by self-questionnaire. It is a collaboration between two international surveys: Health Behaviour in School-aged Children (HBSC) (11, 12) and European School Survey Project on Alcohol and Other Drugs (ESPAD) (13). Through this partnership, researchers provide every two years since 2012 data from adolescents enrolled in the last year of middle school (corresponding to grade 9 of Junior High School in the United States). Surveys took place during spring 2012, 2014, 2016, 2018, and 2021.

To achieve a nationally representative sample of students enrolled in the last year of middle school in metropolitan France, a two-stage cluster sampling method was used for each survey, with schools as a primary sampling unit and classes as a secondary sampling unit. In order to guarantee equal probability of sampling at the student level, schools were selected with a probability proportional to their size, within the database of the Ministry of Education. Two classes were randomly selected in each middle school, and then invited to participate in the survey.

## 2.2. Data collection

At each survey wave, students completed confidential, anonymous, self-completion questionnaires, during dedicated classroom sessions.

### 2.2.1. Life satisfaction

Since 2012, life satisfaction has been measured with the validated Cantril ladder (score 0-10; 10 meaning the best possible life) (8, 9). The full text of the question is as follows: "Here is a picture of a ladder. The top of the ladder '10' is the best possible life for you and the bottom '0' is the worst possible life for you. In general, where on the ladder do you feel you stand at the moment?". In 2021, we also asked students retrospectively about their life satisfaction at the time of the first French COVID-19 national lockdown (March 15-May 11, 2020, see **Supplementary Figure S1**), with an adapted Cantril ladder: "Here is a picture of a ladder. The top of the ladder '10' is the best possible life for you and the bottom '0' is the worst possible life for you. Where on the ladder do you feel you stood *during the lockdown*?". As in previous studies, the score was dichotomized, and respondents with a score of 6 or more were classified as reporting high life satisfaction (8, 14-16).

Further, students who participated in the 2021 survey were categorized into three life satisfaction groups according to their individual changes between 2020 and 2021: improved life satisfaction, no change in life satisfaction, and decreased life satisfaction. A 3-point threshold (greater than or equal to 3) was chosen to categorize
**Conclusions:** This study shows that the way adolescents experienced the first 2020 lockdown in France was not uniform, and that one must consider sex as well as housing and studying conditions when interpreting adolescents' life satisfaction decrease during the COVID-19 pandemic.

KEYWORDS

life satisfaction, adolescents', COVID-19, well-being, mental health, cross-sectional study, school survey

# 1. Introduction

Many studies conducted since 2020 have suggested that the COVID-19 pandemic and its mitigation measures have had numerous psychosocial consequences, including on adolescents' well-being. More specifically, several studies found a decrease in adolescents' quality of life and life satisfaction, and an increase in the incidence of mental health disorders such as anxiety, depressive syndrome, psychosomatic complaints, and suicidal ideation (1-5). Authors identified protective and risk factors of well-being, associated with sociodemographic characteristics, social and family environment, physical environment, and lifestyle. Those findings on adolescents' well-being have been confirmed in France by the Confeado study, which aimed to understand how children and adolescents aged 9-16 years experienced the first lockdown in France (between March and May 2020), and how it may have affected their well-being (6). With 3,898 children and adolescents included, the Confeado study found that better living conditions during lockdown were associated with higher resilience scores. However, few studies have been able to contextualize the impact of the pandemic (and its mitigation measures) on adolescents' well-being and measure it over time (7).

Life satisfaction is a term related to subjective well-being and can be used to summarize how people perceive their life (8). It can be measured by the Cantril ladder, a one-item validated scale that is easy to understand and quick to answer, including by adolescents (8, 9). Life satisfaction among adolescents or young adults seems strongly correlated to life experience and mental health, especially the positive aspects of mental health (8, 10).

Based on data collected from adolescents periodically, the study EnCLASS is a unique opportunity to analyze data over the past decade to identify time trends in life satisfaction before and during the COVID-19 pandemic. Taking those trends into consideration, we further assessed associations between individual changes in life satisfaction among students in their last year of middle school (around 14-15 years) between 2020 and 2021 and housing and studying conditions during the COVID-19 lockdown experimented in March 2020 (measured retrospectively).

# 2. Materials and methods

## 2.1. Study design and sample

Our study used the data collected for the French national survey in middle- and high-school among adolescents on health and substances

(EnCLASS). EnCLASS is a repeated biennial cross-sectional survey conducted in schools in France by self-questionnaire. It is a collaboration between two international surveys: Health Behaviour in School-aged Children (HBSC) (11, 12) and European School Survey Project on Alcohol and Other Drugs (ESPAD) (13). Through this partnership, researchers provide every two years since 2012 data from adolescents enrolled in the last year of middle school (corresponding to grade 9 of Junior High School in the United States). Surveys took place during spring 2012, 2014, 2016, 2018, and 2021.

To achieve a nationally representative sample of students enrolled in the last year of middle school in metropolitan France, a two-stage cluster sampling method was used for each survey, with schools as a primary sampling unit and classes as a secondary sampling unit. In order to guarantee equal probability of sampling at the student level, schools were selected with a probability proportional to their size, within the database of the Ministry of Education. Two classes were randomly selected in each middle school, and then invited to participate in the survey.

## 2.2. Data collection

At each survey wave, students completed confidential, anonymous, self-completion questionnaires, during dedicated classroom sessions.

### 2.2.1. Life satisfaction

Since 2012, life satisfaction has been measured with the validated Cantril ladder (score 0-10; 10 meaning the best possible life) (8, 9). The full text of the question is as follows: "Here is a picture of a ladder. The top of the ladder '10' is the best possible life for you and the bottom '0' is the worst possible life for you. In general, where on the ladder do you feel you stand at the moment?". In 2021, we also asked students retrospectively about their life satisfaction at the time of the first French COVID-19 national lockdown (March 15-May 11, 2020, see **Supplementary Figure S1**), with an adapted Cantril ladder: "Here is a picture of a ladder. The top of the ladder '10' is the best possible life for you and the bottom '0' is the worst possible life for you. Where on the ladder do you feel you stood *during the lockdown*?". As in previous studies, the score was dichotomized, and respondents with a score of 6 or more were classified as reporting high life satisfaction (8, 14-16).

Further, students who participated in the 2021 survey were categorized into three life satisfaction groups according to their individual changes between 2020 and 2021: improved life satisfaction, no change in life satisfaction, and decreased life satisfaction. A 3-point threshold (greater than or equal to 3) was chosen to categorize
the individual changes between 2020 and 2021, corresponding to one
standard deviation of the distribution of the difference calculated for
each student between the 2020 and 2021 scores.

2.2.2. Sociodemographic characteristics

The following sociodemographic characteristics were collected at
each survey wave: sex, educational delay, family structure, and
parental employment. Students with chronic conditions were
identified through a single-item developed for the HBSC survey and
based on a non-categorical approach (17): "Do you have a long-
term illness, disability, or medical condition (such as, diabetes,
arthritis, allergy or cerebral palsy) that was diagnosed by a doctor?"
(yes/no) (14). Family affluence level was measured using the HBSC
family affluence scale (FAS) which included four items in 2012, and
was revised in 2014 into a six-item scale to integrate changes in
living conditions (18, 19). Due to the COVID-19 pandemic, the
scale used in 2021 excluded the item asking students how many
times the family went abroad for a holiday/vacation in the previous
year. Family affluence scores were divided into tertiles defined
within each survey wave, in order to allow comparisons between
surveys: low- and high-affluence groups were defined as the lowest
and the highest tertile, respectively, within each survey wave.

2.2.3. Housing and studying conditions during lockdown

Housing and studying conditions during the lockdown of spring 2020 were retrospectively reported by students in the 2021 survey with yes-no questions asking them whether they: (1) had their own room, (2) had access to a screen to contact classmates or friends online and (3) had access to an outdoor space such as a balcony, a yard, a patio or a garden.

Students' perceptions of study conditions were retrospectively
reported through the following item: "During this first lockdown,
you were able to study in good conditions" with a 5-point Likert
scale (Totally agree/Agree/Neither agree nor disagree/Disagree/
Totally disagree). Then, responses were grouped into three
categories: Good study conditions/Neither good nor bad study
conditions/Bad study conditions.

2.3. Statistical analysis

In order to contextualize individual changes in life satisfaction
between 2020 and 2021, we first examined life satisfaction trends
between 2012 and 2021. Main sample characteristics were
described for each survey year. To compare life satisfaction
between survey waves, Poisson regression models with robust
variance were computed with the survey year as a categorical
variable (20, 21). The models were controlled for educational
delay because this factor was both associated with life satisfaction
and survey year, as practices in France regarding class repetition
changed between 2012 and 2021. Results were presented as
prevalence ratios with 95% confidence intervals (CI); they were
derived from the models to compare the probability of high life
satisfaction in each survey year to that in 2021. The possible
modification effect due to interaction with vulnerability factors

(chronic conditions, sex, FAS level) was examined each
vulnerability factor independently.

Then, socioeconomic characteristics and living conditions during
lockdown were described. We examined the associations between
those factors and categories of changes in life satisfaction between
2020 (retrospective collection) and 2021. We used Chi-squared test
with Rao & Scott's second-order correction and multinomial logistic
regression models with change in life satisfaction as the response
variable (decreased life satisfaction between 2020 and 2021 vs. no
change; improved life satisfaction between 2020 and 2021 vs. no
change). Adjusted models on sex and educational delay were fitted
in order to obtain odds ratios (OR) of the associations with CI.

To correct for nonresponse at the school, class and student levels, calibration weights were used to ensure the representativeness of last year of middle school students, using data from the French Ministry of Education (calibration variables in 2014: class, sex and age; 2018: class, sex, sector (public/private), type of school's municipality (rural/urban); 2021: class, sex, sector). Statistical analyses were performed using Stata version 14.1 and R version 4.2.0 and took into account the calibration weights and the intra-class correlation due to the cluster design of each survey.

2.4. Ethics

Prior to participation, for each survey wave, adolescents and their parents were informed of the rationale of EnCLASS surveys and of their right to object to their participation in the survey. Each wave has been approved by the French national council for statistical information and has been declared to the French national information science and liberties commission.

3. Results

3.1. Trends in life satisfaction between 2012 and 2021

**Table 1** presents samples characteristics and the prevalence of adolescents reporting high life satisfaction by survey year are shown in 2012, 2014, 2016, 2018 and 2021. The frequency distribution of sex was similar between survey years, while the proportion of students who reported chronic conditions, the repartition of the level of family affluence, and the proportion of students with education delay differed. From 2012 to 2018, the proportion of adolescents reporting high life satisfaction was mostly stable and then decreased from 83.8% in 2018 to 77.4% in 2021. The adjusted analyses showed that students surveyed in 2021 were less likely to report high life satisfaction than those surveyed between 2012 and 2018 (**Supplementary Table S1**). While sex and family affluence significantly impacted the relationship between survey years and the probability of reporting high life satisfaction (the decrease in the proportion of students reporting a high life satisfaction between 2012 and 2021 was higher in girls than boys, and higher among those from families with low affluence compared to intermediate affluence), results did not differ according to the presence of a
the individual changes between 2020 and 2021, corresponding to one
standard deviation of the distribution of the difference calculated for
each student between the 2020 and 2021 scores.

2.2.2. Sociodemographic characteristics

The following sociodemographic characteristics were collected at
each survey wave: sex, educational delay, family structure, and
parental employment. Students with chronic conditions were
identified through a single-item developed for the HBSC survey and
based on a non-categorical approach (17): "Do you have a long-
term illness, disability, or medical condition (such as, diabetes,
arthritis, allergy or cerebral palsy) that was diagnosed by a doctor?"
(yes/no) (14). Family affluence level was measured using the HBSC
family affluence scale (FAS) which included four items in 2012, and
was revised in 2014 into a six-item scale to integrate changes in
living conditions (18, 19). Due to the COVID-19 pandemic, the
scale used in 2021 excluded the item asking students how many
times the family went abroad for a holiday/vacation in the previous
year. Family affluence scores were divided into tertiles defined
within each survey wave, in order to allow comparisons between
surveys: low- and high-affluence groups were defined as the lowest
and the highest tertile, respectively, within each survey wave.

2.2.3. Housing and studying conditions during lockdown

Housing and studying conditions during the lockdown of spring 2020 were retrospectively reported by students in the 2021 survey with yes-no questions asking them whether they: (1) had their own room, (2) had access to a screen to contact classmates or friends online and (3) had access to an outdoor space such as a balcony, a yard, a patio or a garden.

Students' perceptions of study conditions were retrospectively
reported through the following item: "During this first lockdown,
you were able to study in good conditions" with a 5-point Likert
scale (Totally agree/Agree/Neither agree nor disagree/Disagree/
Totally disagree). Then, responses were grouped into three
categories: Good study conditions/Neither good nor bad study
conditions/Bad study conditions.

2.3. Statistical analysis

In order to contextualize individual changes in life satisfaction
between 2020 and 2021, we first examined life satisfaction trends
between 2012 and 2021. Main sample characteristics were
described for each survey year. To compare life satisfaction
between survey waves, Poisson regression models with robust
variance were computed with the survey year as a categorical
variable (20, 21). The models were controlled for educational
delay because this factor was both associated with life satisfaction
and survey year, as practices in France regarding class repetition
changed between 2012 and 2021. Results were presented as
prevalence ratios with 95% confidence intervals (CI); they were
derived from the models to compare the probability of high life
satisfaction in each survey year to that in 2021. The possible
modification effect due to interaction with vulnerability factors

(chronic conditions, sex, FAS level) was examined each
vulnerability factor independently.

Then, socioeconomic characteristics and living conditions during
lockdown were described. We examined the associations between
those factors and categories of changes in life satisfaction between
2020 (retrospective collection) and 2021. We used Chi-squared test
with Rao & Scott's second-order correction and multinomial logistic
regression models with change in life satisfaction as the response
variable (decreased life satisfaction between 2020 and 2021 vs. no
change; improved life satisfaction between 2020 and 2021 vs. no
change). Adjusted models on sex and educational delay were fitted
in order to obtain odds ratios (OR) of the associations with CI.

To correct for nonresponse at the school, class and student levels,
calibration weights were used to ensure the representativeness of last
year of middle school students, using data from the French Ministry
of Education (calibration variables in 2014: class, sex and age; 2018:
class, sex, sector (public/private), type of school's municipality
(rural/urban); 2021: class, sex, sector). Statistical analyses were
performed using Stata version 14.1 and R version 4.2.0 and took
into account the calibration weights and the intra-class correlation
due to the cluster design of each survey.

2.4. Ethics

Prior to participation, for each survey wave, adolescents and
their parents were informed of the rationale of EnCLASS surveys
and of their right to object to their participation in the survey.
Each wave has been approved by the French national council for
statistical information and has been declared to the French
national information science and liberties commission.

3. Results

3.1. Trends in life satisfaction between 2012 and 2021

**Table 1** presents samples characteristics and the prevalence of
adolescents reporting high life satisfaction by survey year are shown
in 2012, 2014, 2016, 2018 and 2021. The frequency distribution of
sex was similar between survey years, while the proportion of
students who reported chronic conditions, the repartition of the
level of family affluence, and the proportion of students with
education delay differed. From 2012 to 2018, the proportion of
adolescents reporting high life satisfaction was mostly stable and
then decreased from 83.8% in 2018 to 77.4% in 2021. The adjusted
analyses showed that students surveyed in 2021 were less likely to
report high life satisfaction than those surveyed between 2012 and
2018 (Supplementary Table S1). While sex and family affluence
significantly impacted the relationship between survey years and the
probability of reporting high life satisfaction (the decrease in the
proportion of students reporting a high life satisfaction between
2012 and 2021 was higher in girls than boys, and higher among
those from families with low affluence compared to intermediate
affluence), results did not differ according to the presence of a
<table><caption>TABLE 1 Sample characteristics and prevalence of high life satisfaction.</caption><thead><tr><th>Survey year</th><th>2012</th><th>2014</th><th>2016</th><th>2018</th><th>2021</th><th>p-value<sup>a</sup></th></tr><tr><td></td><td>n = 4,887</td><td>n = 4,694</td><td>n = 3,313</td><td>n = 2,832</td><td>n = 1,960</td><td></td></tr></thead><tbody><tr><td>Age at questionnaire administration (years)<sup>b</sup></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Mean (standard error)</td><td>15.1 (0.01)</td><td>15.0 (0.02)</td><td>15.1 (0.02)</td><td>15.0 (0.01)</td><td>14.7 (0.02)</td><td>&lt;0.001</td></tr><tr><td>Sex, weighted %</td><td></td><td></td><td></td><td></td><td></td><td>0.306</td></tr><tr><td>Boys</td><td>47.8</td><td>48.7</td><td>48.4</td><td>51.1</td><td>50.7</td><td></td></tr><tr><td>Girls</td><td>52.2</td><td>51.3</td><td>51.6</td><td>48.9</td><td>49.3</td><td></td></tr><tr><td>Chronic condition (CC) status, weighted %</td><td></td><td></td><td></td><td></td><td></td><td>&lt;0.001</td></tr><tr><td>Without CC</td><td>82.5</td><td>79.6</td><td>82.4</td><td>82.1</td><td>84.5</td><td></td></tr><tr><td>With CC</td><td>17.5</td><td>20.4</td><td>17.6</td><td>17.9</td><td>15.5</td><td></td></tr><tr><td>Family affluence level</td><td></td><td></td><td></td><td></td><td></td><td>0.001</td></tr><tr><td>Low (tertile 1)</td><td>-</td><td>43.0</td><td>47.9</td><td>46.1</td><td>43.8</td><td></td></tr><tr><td>Medium (tertile 2)</td><td>-</td><td>31.6</td><td>33.6</td><td>34.1</td><td>32.2</td><td></td></tr><tr><td>High (tertile 3)</td><td>-</td><td>25.4</td><td>18.5</td><td>19.8</td><td>24.1</td><td></td></tr><tr><td>Educational delay, weighted %</td><td></td><td></td><td></td><td></td><td></td><td>&lt;0.001</td></tr><tr><td>No</td><td>72.2</td><td>76.0</td><td>79.9</td><td>82.3</td><td>86.5</td><td></td></tr><tr><td>Yes</td><td>27.8</td><td>24.0</td><td>20.1</td><td>17.7</td><td>13.5</td><td></td></tr><tr><td>Life satisfaction, Cantril score</td><td></td><td></td><td></td><td></td><td></td><td>0.025</td></tr><tr><td>Median</td><td>7</td><td>7</td><td>7</td><td>8</td><td>7</td><td></td></tr><tr><td>IQR<sup>c</sup></td><td>(6–8)</td><td>(6–8)</td><td>(6–8)</td><td>(6–9)</td><td>(6–8)</td><td></td></tr><tr><td>High life satisfaction<sup>d</sup> (%)</td><td>81.0</td><td>80.1</td><td>80.7</td><td>83.8</td><td>77.4</td><td></td></tr></tbody></table>

chronic condition. The predicted probabilities of reporting high life satisfaction computed from adjusted models are graphically provided in **Figure 1** in relation to the survey year. The estimate for life satisfaction in 2020 reported retrospectively by students in the 2021 survey is also reported in **Figure 1**.

In 2021, the sample consisted of 1,960 adolescents, of whom 49.3% were girls, 15.5% reported having a chronic condition, and 43.8% were from a family with low affluence (Table 1). Moreover, 66.8% of adolescents lived in a nuclear family and 76.7% had both parents employed (Table 2). During the 2020 lockdown, 80.9% of adolescents

<figure><img src="image_3.png" /><figcaption>FIGURE 1
Evolution in the proportion of students with high life satisfaction between 2012 and 2021.</figcaption></figure>

<footnote>aChi-squared test with Rao & Scott's second-order correction.</footnote>

<footnote>bIn 2018, a national law changed practices in France regarding class repetition, hence educational delay.</footnote>

<footnote>cIQR: Inter quartile range.</footnote>

<footnote>dCantril score ≥6.</footnote>
<table><caption>TABLE 1 Sample characteristics and prevalence of high life satisfaction.</caption><thead><tr><th>Survey year</th><th>2012</th><th>2014</th><th>2016</th><th>2018</th><th>2021</th><th>p-value<sup>a</sup></th></tr><tr><td></td><td>n = 4,887</td><td>n = 4,694</td><td>n = 3,313</td><td>n = 2,832</td><td>n = 1,960</td><td></td></tr></thead><tbody><tr><td>Age at questionnaire administration (years)<sup>b</sup></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Mean (standard error)</td><td>15.1 (0.01)</td><td>15.0 (0.02)</td><td>15.1 (0.02)</td><td>15.0 (0.01)</td><td>14.7 (0.02)</td><td>&lt;0.001</td></tr><tr><td>Sex, weighted %</td><td></td><td></td><td></td><td></td><td></td><td>0.306</td></tr><tr><td>Boys</td><td>47.8</td><td>48.7</td><td>48.4</td><td>51.1</td><td>50.7</td><td></td></tr><tr><td>Girls</td><td>52.2</td><td>51.3</td><td>51.6</td><td>48.9</td><td>49.3</td><td></td></tr><tr><td>Chronic condition (CC) status, weighted %</td><td></td><td></td><td></td><td></td><td></td><td>&lt;0.001</td></tr><tr><td>Without CC</td><td>82.5</td><td>79.6</td><td>82.4</td><td>82.1</td><td>84.5</td><td></td></tr><tr><td>With CC</td><td>17.5</td><td>20.4</td><td>17.6</td><td>17.9</td><td>15.5</td><td></td></tr><tr><td>Family affluence level</td><td></td><td></td><td></td><td></td><td></td><td>0.001</td></tr><tr><td>Low (tertile 1)</td><td>-</td><td>43.0</td><td>47.9</td><td>46.1</td><td>43.8</td><td></td></tr><tr><td>Medium (tertile 2)</td><td>-</td><td>31.6</td><td>33.6</td><td>34.1</td><td>32.2</td><td></td></tr><tr><td>High (tertile 3)</td><td>-</td><td>25.4</td><td>18.5</td><td>19.8</td><td>24.1</td><td></td></tr><tr><td>Educational delay, weighted %</td><td></td><td></td><td></td><td></td><td></td><td>&lt;0.001</td></tr><tr><td>No</td><td>72.2</td><td>76.0</td><td>79.9</td><td>82.3</td><td>86.5</td><td></td></tr><tr><td>Yes</td><td>27.8</td><td>24.0</td><td>20.1</td><td>17.7</td><td>13.5</td><td></td></tr><tr><td>Life satisfaction, Cantril score</td><td></td><td></td><td></td><td></td><td></td><td>0.025</td></tr><tr><td>Median</td><td>7</td><td>7</td><td>7</td><td>8</td><td>7</td><td></td></tr><tr><td>IQR<sup>c</sup></td><td>(6–8)</td><td>(6–8)</td><td>(6–8)</td><td>(6–9)</td><td>(6–8)</td><td></td></tr><tr><td>High life satisfaction<sup>d</sup> (%)</td><td>81.0</td><td>80.1</td><td>80.7</td><td>83.8</td><td>77.4</td><td></td></tr></tbody></table>

chronic condition. The predicted probabilities of reporting high life satisfaction computed from adjusted models are graphically provided in **Figure 1** in relation to the survey year. The estimate for life satisfaction in 2020 reported retrospectively by students in the 2021 survey is also reported in **Figure 1**.

In 2021, the sample consisted of 1,960 adolescents, of whom 49.3% were girls, 15.5% reported having a chronic condition, and 43.8% were from a family with low affluence (Table 1). Moreover, 66.8% of adolescents lived in a nuclear family and 76.7% had both parents employed (Table 2). During the 2020 lockdown, 80.9% of adolescents

<figure><img src="image_3.png" /><figcaption>FIGURE 1
Evolution in the proportion of students with high life satisfaction between 2012 and 2021.</figcaption></figure>

<footnote>aChi-squared test with Rao & Scott's second-order correction.</footnote>

<footnote>bIn 2018, a national law changed practices in France regarding class repetition, hence educational delay.</footnote>

<footnote>cIQR: Inter quartile range.</footnote>

<footnote>dCantril score ≥6.</footnote>
<table><caption>TABLE 2 Socioeconomic characteristics, housing and studying conditions during the 2020 lockdown, among students enrolled in the 2021 survey.</caption><thead><tr><th></th><th>Total (N = 1,960)<sup>a</sup></th></tr></thead><tbody><tr><td colspan="2"><strong>Socioeconomic variables in 2021</strong></td></tr><tr><td><strong>Family structure, N (%)</strong></td><td></td></tr><tr><td>Nuclear family</td><td>1,285 (66.8)</td></tr><tr><td>Single parents or others</td><td>218 (10.8)</td></tr><tr><td>Reconstructed family</td><td>442 (22.4)</td></tr><tr><td>Missing</td><td>15</td></tr><tr><td><strong>Parental employment, N (%)</strong></td><td></td></tr><tr><td>Both parents employed</td><td>1,320 (76.7)</td></tr><tr><td>One parent employed</td><td>364 (20.9)</td></tr><tr><td>Both parents unemployed</td><td>46 (2.5)</td></tr><tr><td>Missing</td><td>230</td></tr><tr><td><strong>Housing and studying conditions during the 2020 lockdown</strong></td><td></td></tr><tr><td>Have had their own room: yes, N (%)</td><td>1,570 (80.9)</td></tr><tr><td>Missing</td><td>33</td></tr><tr><td>Have had access to an outdoor space (balcony, yard, patio, or garden): yes, N (%)</td><td>1,727 (90.2)</td></tr><tr><td>Missing</td><td>36</td></tr><tr><td>Have had access to a screen to contact classmates or friends online: yes, N (%)</td><td>1,624 (86.7)</td></tr><tr><td>Missing</td><td>71</td></tr><tr><td><strong>Study conditions, N (%)</strong></td><td></td></tr><tr><td>Bad study conditions</td><td>430 (22.5)</td></tr><tr><td>Neither good nor bad study conditions</td><td>370 (19.2)</td></tr><tr><td>Good study conditions</td><td>1,092 (58.3)</td></tr><tr><td>Missing</td><td>68</td></tr></tbody></table>

had their own room, 90.2% had access to an outdoor space, and 86.7% had access to a screen to contact classmates or friends online. On the other hand, almost a quarter of adolescents (22.5%) reported they could not study in good conditions during this lockdown.

## 3.2. Description of individual changes in life satisfaction between 2020 and 2021

Between 2020 and 2021, a third of the adolescents reported a change in their life satisfaction (improved: 16.3%; worsened 17.7%) (Table 3). The distribution of the Cantril score in 2021 followed an asymmetric normal distribution with a mean score of 8, whereas the distribution of the retrospective scores regarding life satisfaction during the 2020 lockdown is different, with more responses towards the extreme scores of the scale, especially 10 (Figure 2).

## 3.3. Factors associated with 2020–2021 changes in life satisfaction

The comparison of changes in life satisfaction (in the 3 described groups) according to sociodemographic characteristics, housing, and studying conditions during the 2020 lockdown is presented in Table 3. The multinomial logistic regression results are presented in Table 4 for the adjusted model and in Supplementary

Table S2 for the unadjusted model. Overall, girls were more likely to have experimented a change in their life satisfaction between the lockdown of 2020 and 2021 compared to boys (aOR of decreased vs. stable life satisfaction: 1.43, 95%CI, 1.14–1.79; aOR of increased vs. stable life satisfaction: 1.82, 95%CI, 1.40–2.37). Adolescents living in reconstructed families were more likely to report a decrease in life satisfaction between the 2020 lockdown period and 2021 compared to their peers living in a nuclear family (aOR 2.09, 95%CI, 1.58–2.77). There was no significant association between having a chronic condition and a change in life satisfaction. Regarding housing and studying conditions during the lockdown of spring 2020, adolescents who did not have their own room nor access to a screen to contact classmates or friends online were more likely to report a decrease in their life satisfaction between the 2020 lockdown and 2021 (aOR 1.58, 95% CI, 1.16–2.15 and aOR 1.47, 95%CI, 1.09–1.98; respectively).

# 4. Discussion

## 4.1. Main findings

This study investigates temporal trends in life satisfaction among adolescents aged 14–15 years enrolled in middle schools in France during the COVID-19 pandemic. We found an overall slight decrease in the prevalence of adolescents reporting high life satisfaction between 2012 and 2021. The lowest proportion of adolescents reporting high life satisfaction was observed in 2021 (77.4%), with different patterns regarding sex and family affluence. Regarding individual changes in life satisfaction between the 2020 lockdown and 2021, we found that life satisfaction improved overall for 16.3% of French adolescents and decreased for 17.7%. According to adjusted models, being a girl, living in a reconstructed family (in 2021), not having their own bedroom, and not having access to a screen to contact classmates or friends online during the 2020 COVID-19 lockdown were related to a decrease in life satisfaction.

## 4.2. Interpretation

The overall decrease in life satisfaction we observed in our study between 2012 and 2021, is somewhat in line with a global decline in adolescents’ mental health, including students’ life satisfaction, observed since the early 2000s’ in European countries (15, 16). Studying the global burden of non-communicable diseases among adolescents in the European Union in 2019, Armocida et al. found an increase in years of life lost due to mental disorders between 1990 and 2019 (22). More recently, several systematic reviews found that the COVID-19 pandemic has impacted adolescents’ mental health, with an increase in depression and anxiety symptoms and high levels of fear concerning the pandemic and its impact on their lives (3, 23). In France, a decrease in the number of self-harm acts and suicide attempts among children and adolescents was observed during the first three months of the pandemic and the

<footnote>aUnweighted count (Weighted % on complete data).</footnote>
<table><caption>TABLE 2 Socioeconomic characteristics, housing and studying conditions during the 2020 lockdown, among students enrolled in the 2021 survey.</caption><thead><tr><th></th><th>Total (N = 1,960)<sup>a</sup></th></tr></thead><tbody><tr><td colspan="2"><strong>Socioeconomic variables in 2021</strong></td></tr><tr><td><strong>Family structure, N (%)</strong></td><td></td></tr><tr><td>Nuclear family</td><td>1,285 (66.8)</td></tr><tr><td>Single parents or others</td><td>218 (10.8)</td></tr><tr><td>Reconstructed family</td><td>442 (22.4)</td></tr><tr><td>Missing</td><td>15</td></tr><tr><td><strong>Parental employment, N (%)</strong></td><td></td></tr><tr><td>Both parents employed</td><td>1,320 (76.7)</td></tr><tr><td>One parent employed</td><td>364 (20.9)</td></tr><tr><td>Both parents unemployed</td><td>46 (2.5)</td></tr><tr><td>Missing</td><td>230</td></tr><tr><td><strong>Housing and studying conditions during the 2020 lockdown</strong></td><td></td></tr><tr><td>Have had their own room: yes, N (%)</td><td>1,570 (80.9)</td></tr><tr><td>Missing</td><td>33</td></tr><tr><td>Have had access to an outdoor space (balcony, yard, patio, or garden): yes, N (%)</td><td>1,727 (90.2)</td></tr><tr><td>Missing</td><td>36</td></tr><tr><td>Have had access to a screen to contact classmates or friends online: yes, N (%)</td><td>1,624 (86.7)</td></tr><tr><td>Missing</td><td>71</td></tr><tr><td><strong>Study conditions, N (%)</strong></td><td></td></tr><tr><td>Bad study conditions</td><td>430 (22.5)</td></tr><tr><td>Neither good nor bad study conditions</td><td>370 (19.2)</td></tr><tr><td>Good study conditions</td><td>1,092 (58.3)</td></tr><tr><td>Missing</td><td>68</td></tr></tbody></table>

had their own room, 90.2% had access to an outdoor space, and 86.7% had access to a screen to contact classmates or friends online. On the other hand, almost a quarter of adolescents (22.5%) reported they could not study in good conditions during this lockdown.

## 3.2. Description of individual changes in life satisfaction between 2020 and 2021

Between 2020 and 2021, a third of the adolescents reported a change in their life satisfaction (improved: 16.3%; worsened 17.7%) (Table 3). The distribution of the Cantril score in 2021 followed an asymmetric normal distribution with a mean score of 8, whereas the distribution of the retrospective scores regarding life satisfaction during the 2020 lockdown is different, with more responses towards the extreme scores of the scale, especially 10 (Figure 2).

## 3.3. Factors associated with 2020–2021 changes in life satisfaction

The comparison of changes in life satisfaction (in the 3 described groups) according to sociodemographic characteristics, housing, and studying conditions during the 2020 lockdown is presented in Table 3. The multinomial logistic regression results are presented in Table 4 for the adjusted model and in Supplementary

Table S2 for the unadjusted model. Overall, girls were more likely to have experimented a change in their life satisfaction between the lockdown of 2020 and 2021 compared to boys (aOR of decreased vs. stable life satisfaction: 1.43, 95%CI, 1.14–1.79; aOR of increased vs. stable life satisfaction: 1.82, 95%CI, 1.40–2.37). Adolescents living in reconstructed families were more likely to report a decrease in life satisfaction between the 2020 lockdown period and 2021 compared to their peers living in a nuclear family (aOR 2.09, 95%CI, 1.58–2.77). There was no significant association between having a chronic condition and a change in life satisfaction. Regarding housing and studying conditions during the lockdown of spring 2020, adolescents who did not have their own room nor access to a screen to contact classmates or friends online were more likely to report a decrease in their life satisfaction between the 2020 lockdown and 2021 (aOR 1.58, 95% CI, 1.16–2.15 and aOR 1.47, 95%CI, 1.09–1.98; respectively).

# 4. Discussion

## 4.1. Main findings

This study investigates temporal trends in life satisfaction among adolescents aged 14–15 years enrolled in middle schools in France during the COVID-19 pandemic. We found an overall slight decrease in the prevalence of adolescents reporting high life satisfaction between 2012 and 2021. The lowest proportion of adolescents reporting high life satisfaction was observed in 2021 (77.4%), with different patterns regarding sex and family affluence. Regarding individual changes in life satisfaction between the 2020 lockdown and 2021, we found that life satisfaction improved overall for 16.3% of French adolescents and decreased for 17.7%. According to adjusted models, being a girl, living in a reconstructed family (in 2021), not having their own bedroom, and not having access to a screen to contact classmates or friends online during the 2020 COVID-19 lockdown were related to a decrease in life satisfaction.

## 4.2. Interpretation

The overall decrease in life satisfaction we observed in our study between 2012 and 2021, is somewhat in line with a global decline in adolescents’ mental health, including students’ life satisfaction, observed since the early 2000s’ in European countries (15, 16). Studying the global burden of non-communicable diseases among adolescents in the European Union in 2019, Armocida et al. found an increase in years of life lost due to mental disorders between 1990 and 2019 (22). More recently, several systematic reviews found that the COVID-19 pandemic has impacted adolescents’ mental health, with an increase in depression and anxiety symptoms and high levels of fear concerning the pandemic and its impact on their lives (3, 23). In France, a decrease in the number of self-harm acts and suicide attempts among children and adolescents was observed during the first three months of the pandemic and the

<footnote>aUnweighted count (Weighted % on complete data).</footnote>
<table><caption>TABLE 3 Individual changes in life satisfaction between 2020 (retrospective) and 2021 according to housing and studying conditions during lockdown (n = 1,916): bivariate analysis.</caption><thead><tr><th rowspan="3"></th><th colspan="2">Life satisfaction scores</th><th colspan="3">Individual changes between 2020 and 2021<sup>a</sup></th><th rowspan="3">p-value<sup>b</sup></th></tr><tr><th>2020</th><th>2021</th><th rowspan="2">Decreased life satisfaction (n = 337)</th><th rowspan="2">No change in life satisfaction (n = 1,269)</th><th rowspan="2">Improved life satisfaction (n = 310)</th></tr><tr><th>Median (Q1-Q3)</th><th>Median (Q1-Q3)</th></tr></thead><tbody><tr><td>Total</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>337 (17.7%)</td><td>1,269 (66.0%)</td><td>310 (16.3%)</td><td></td></tr><tr><td>Sex</td><td></td><td></td><td></td><td></td><td></td><td>&lt;0.001</td></tr><tr><td>Boy</td><td>8 (6, 9)</td><td>8 (6, 8)</td><td>154 (16.1%)</td><td>678 (70.9%)</td><td>123 (12.9%)</td><td></td></tr><tr><td>Girl</td><td>7 (5, 9)</td><td>7 (5, 8)</td><td>183 (19.3%)</td><td>591 (60.8%)</td><td>187 (19.8%)</td><td></td></tr><tr><td>Educational delay in 2021</td><td></td><td></td><td></td><td></td><td></td><td>0.200</td></tr><tr><td>Yes</td><td>7 (5, 9)</td><td>7 (5, 8)</td><td>46 (21.3%)</td><td>125 (59.8%)</td><td>38 (18.9%)</td><td></td></tr><tr><td>No</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>291 (17.3%)</td><td>1,144 (66.7%)</td><td>272 (16.0%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>0</td><td>0</td><td>0</td><td></td></tr><tr><td>Family structure in 2021</td><td></td><td></td><td></td><td></td><td></td><td>&lt;0.001</td></tr><tr><td>Nuclear family</td><td>8 (6, 9)</td><td>7 (6, 8)</td><td>186 (14.6%)</td><td>882 (69.8%)</td><td>193 (15.6%)</td><td></td></tr><tr><td>Single parents or others</td><td>7 (5, 9)</td><td>7 (5, 8)</td><td>44 (19.9%)</td><td>128 (59.6%)</td><td>45 (20.4%)</td><td></td></tr><tr><td>Reconstructed family</td><td>7 (5, 9)</td><td>6 (5, 8)</td><td>104 (26.0%)</td><td>253 (57.9%)</td><td>68 (16.1%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>3</td><td>6</td><td>4</td><td></td></tr><tr><td>Parental employment in 2021</td><td></td><td></td><td></td><td></td><td></td><td>0.500</td></tr><tr><td>Both parents employed</td><td>8 (6, 9)</td><td>7 (6, 8)</td><td>203 (15.6%)</td><td>895 (68.8%)</td><td>203 (15.7%)</td><td></td></tr><tr><td>One parent employed</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>63 (16.9%)</td><td>231 (65.9%)</td><td>59 (17.2%)</td><td></td></tr><tr><td>Both parents unemployed</td><td>7 (4, 9)</td><td>7 (4, 8)</td><td>10 (24.2%)</td><td>23 (56.8%)</td><td>7 (19.1%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>61</td><td>120</td><td>41</td><td></td></tr><tr><td>Having a chronic condition</td><td></td><td></td><td></td><td></td><td></td><td>0.200</td></tr><tr><td>Yes</td><td>7 (5, 9)</td><td>7 (5, 8)</td><td>55 (21.0%)</td><td>183 (64.7%)</td><td>41 (14.4%)</td><td></td></tr><tr><td>No</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>275 (17.0%)</td><td>1,074 (66.4%)</td><td>264 (16.6%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>7</td><td>12</td><td>5</td><td></td></tr><tr><td>Have had their own room during the lockdown</td><td></td><td></td><td></td><td></td><td></td><td>0.008</td></tr><tr><td>Yes</td><td>8 (6, 9)</td><td>7 (6, 8)</td><td>253 (16.4%)</td><td>1,047 (67.5%)</td><td>245 (16.0%)</td><td></td></tr><tr><td>No</td><td>8 (5, 9)</td><td>7 (5, 8)</td><td>82 (23.5%)</td><td>210 (59.3%)</td><td>60 (17.2%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>2</td><td>12</td><td>5</td><td></td></tr><tr><td>Have had access to an outdoor space during the lockdown</td><td></td><td></td><td></td><td></td><td></td><td>0.700</td></tr><tr><td>Yes</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>302 (18.0%)</td><td>1,124 (65.5%)</td><td>279 (16.5%)</td><td></td></tr><tr><td>No</td><td>8 (5, 9)</td><td>6 (5, 8)</td><td>33 (16.4%)</td><td>130 (68.6%)</td><td>27 (15.0%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>2</td><td>15</td><td>4</td><td></td></tr><tr><td>Have had access to a screen to contact classmates or friends online during the lockdown</td><td></td><td></td><td></td><td></td><td></td><td>0.200</td></tr><tr><td>Yes</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>268 (16.9%)</td><td>1,076 (66.6%)</td><td>263 (16.5%)</td><td></td></tr><tr><td>No</td><td>8 (5, 10)</td><td>7 (5, 8)</td><td>57 (22.1%)</td><td>162 (62.2%)</td><td>39 (15.7%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>12</td><td>31</td><td>8</td><td></td></tr><tr><td>Study conditions during the lockdown</td><td></td><td></td><td></td><td></td><td></td><td>0.002</td></tr><tr><td>Bad study conditions</td><td>7 (4, 9)</td><td>6 (5, 8)</td><td>85 (20.1%)</td><td>242 (57.3%)</td><td>100 (22.7%)</td><td></td></tr><tr><td>Neither good nor bad study conditions</td><td>7 (5, 9)</td><td>7 (6, 8)</td><td>59 (15.9%)</td><td>249 (67.5%)</td><td>58 (16.6%)</td><td></td></tr><tr><td>Good study conditions</td><td>8 (6, 9)</td><td>8 (6, 9)</td><td>181 (17.0%)</td><td>751 (69.0%)</td><td>145 (14.0%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>12</td><td>27</td><td>7</td><td></td></tr></tbody></table>

first lockdown, followed by a consequent increase in the second semester of the same year (24, 25).

Among the underlying factors, sex was strongly associated with changes in life satisfaction over time. Indeed, in line with previous literature, girls are less likely to have high life satisfaction compared to boys (8, 26). Our findings confirmed this tendency for girls to report worse life satisfaction over the years, with a widening gender gap observed in 2021. Regarding the effect of the pandemic on

mental health, results vary between studies. Vandentorren et al. (6) found that girls' mental health was more impacted by the pandemic in France, whereas Ravens-Sieberer et al. (2) found that in Germany, unlike in France, being a girl and older was a resource resilience factor, with fewer mental health problems. Adolescents from families from a lower socioeconomic background also appeared less likely to report high life satisfaction, as observed in other studies (27, 28). They may have had more often adverse experiences during the

<footnote><sup>a</sup>Unweighted count (Weighted %).</footnote>

<footnote><sup>b</sup>Chi-squared test with Rao & Scott's second-order correction.</footnote>
<table><caption>TABLE 3 Individual changes in life satisfaction between 2020 (retrospective) and 2021 according to housing and studying conditions during lockdown (n = 1,916): bivariate analysis.</caption><thead><tr><th rowspan="3"></th><th colspan="2">Life satisfaction scores</th><th colspan="3">Individual changes between 2020 and 2021<sup>a</sup></th><th rowspan="3">p-value<sup>b</sup></th></tr><tr><th>2020</th><th>2021</th><th rowspan="2">Decreased life satisfaction<br>(n = 337)</th><th rowspan="2">No change in life satisfaction<br>(n = 1,269)</th><th rowspan="2">Improved life satisfaction<br>(n = 310)</th></tr><tr><th>Median (Q1-Q3)</th><th>Median (Q1-Q3)</th></tr></thead><tbody><tr><td>Total</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>337 (17.7%)</td><td>1,269 (66.0%)</td><td>310 (16.3%)</td><td></td></tr><tr><td>Sex</td><td></td><td></td><td></td><td></td><td></td><td>&lt;0.001</td></tr><tr><td>Boy</td><td>8 (6, 9)</td><td>8 (6, 8)</td><td>154 (16.1%)</td><td>678 (70.9%)</td><td>123 (12.9%)</td><td></td></tr><tr><td>Girl</td><td>7 (5, 9)</td><td>7 (5, 8)</td><td>183 (19.3%)</td><td>591 (60.8%)</td><td>187 (19.8%)</td><td></td></tr><tr><td>Educational delay in 2021</td><td></td><td></td><td></td><td></td><td></td><td>0.200</td></tr><tr><td>Yes</td><td>7 (5, 9)</td><td>7 (5, 8)</td><td>46 (21.3%)</td><td>125 (59.8%)</td><td>38 (18.9%)</td><td></td></tr><tr><td>No</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>291 (17.3%)</td><td>1,144 (66.7%)</td><td>272 (16.0%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>0</td><td>0</td><td>0</td><td></td></tr><tr><td>Family structure in 2021</td><td></td><td></td><td></td><td></td><td></td><td>&lt;0.001</td></tr><tr><td>Nuclear family</td><td>8 (6, 9)</td><td>7 (6, 8)</td><td>186 (14.6%)</td><td>882 (69.8%)</td><td>193 (15.6%)</td><td></td></tr><tr><td>Single parents or others</td><td>7 (5, 9)</td><td>7 (5, 8)</td><td>44 (19.9%)</td><td>128 (59.6%)</td><td>45 (20.4%)</td><td></td></tr><tr><td>Reconstructed family</td><td>7 (5, 9)</td><td>6 (5, 8)</td><td>104 (26.0%)</td><td>253 (57.9%)</td><td>68 (16.1%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>3</td><td>6</td><td>4</td><td></td></tr><tr><td>Parental employment in 2021</td><td></td><td></td><td></td><td></td><td></td><td>0.500</td></tr><tr><td>Both parents employed</td><td>8 (6, 9)</td><td>7 (6, 8)</td><td>203 (15.6%)</td><td>895 (68.8%)</td><td>203 (15.7%)</td><td></td></tr><tr><td>One parent employed</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>63 (16.9%)</td><td>231 (65.9%)</td><td>59 (17.2%)</td><td></td></tr><tr><td>Both parents unemployed</td><td>7 (4, 9)</td><td>7 (4, 8)</td><td>10 (24.2%)</td><td>23 (56.8%)</td><td>7 (19.1%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>61</td><td>120</td><td>41</td><td></td></tr><tr><td>Having a chronic condition</td><td></td><td></td><td></td><td></td><td></td><td>0.200</td></tr><tr><td>Yes</td><td>7 (5, 9)</td><td>7 (5, 8)</td><td>55 (21.0%)</td><td>183 (64.7%)</td><td>41 (14.4%)</td><td></td></tr><tr><td>No</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>275 (17.0%)</td><td>1,074 (66.4%)</td><td>264 (16.6%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>7</td><td>12</td><td>5</td><td></td></tr><tr><td>Have had their own room during the lockdown</td><td></td><td></td><td></td><td></td><td></td><td>0.008</td></tr><tr><td>Yes</td><td>8 (6, 9)</td><td>7 (6, 8)</td><td>253 (16.4%)</td><td>1,047 (67.5%)</td><td>245 (16.0%)</td><td></td></tr><tr><td>No</td><td>8 (5, 9)</td><td>7 (5, 8)</td><td>82 (23.5%)</td><td>210 (59.3%)</td><td>60 (17.2%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>2</td><td>12</td><td>5</td><td></td></tr><tr><td>Have had access to an outdoor space during the lockdown</td><td></td><td></td><td></td><td></td><td></td><td>0.700</td></tr><tr><td>Yes</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>302 (18.0%)</td><td>1,124 (65.5%)</td><td>279 (16.5%)</td><td></td></tr><tr><td>No</td><td>8 (5, 9)</td><td>6 (5, 8)</td><td>33 (16.4%)</td><td>130 (68.6%)</td><td>27 (15.0%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>2</td><td>15</td><td>4</td><td></td></tr><tr><td>Have had access to a screen to contact classmates or friends online during the lockdown</td><td></td><td></td><td></td><td></td><td></td><td>0.200</td></tr><tr><td>Yes</td><td>8 (5, 9)</td><td>7 (6, 8)</td><td>268 (16.9%)</td><td>1,076 (66.6%)</td><td>263 (16.5%)</td><td></td></tr><tr><td>No</td><td>8 (5, 10)</td><td>7 (5, 8)</td><td>57 (22.1%)</td><td>162 (62.2%)</td><td>39 (15.7%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>12</td><td>31</td><td>8</td><td></td></tr><tr><td>Study conditions during the lockdown</td><td></td><td></td><td></td><td></td><td></td><td>0.002</td></tr><tr><td>Bad study conditions</td><td>7 (4, 9)</td><td>6 (5, 8)</td><td>85 (20.1%)</td><td>242 (57.3%)</td><td>100 (22.7%)</td><td></td></tr><tr><td>Neither good nor bad study conditions</td><td>7 (5, 9)</td><td>7 (6, 8)</td><td>59 (15.9%)</td><td>249 (67.5%)</td><td>58 (16.6%)</td><td></td></tr><tr><td>Good study conditions</td><td>8 (6, 9)</td><td>8 (6, 9)</td><td>181 (17.0%)</td><td>751 (69.0%)</td><td>145 (14.0%)</td><td></td></tr><tr><td>Missing</td><td></td><td></td><td>12</td><td>27</td><td>7</td><td></td></tr></tbody></table>

first lockdown, followed by a consequent increase in the second semester of the same year (24, 25).

Among the underlying factors, sex was strongly associated with changes in life satisfaction over time. Indeed, in line with previous literature, girls are less likely to have high life satisfaction compared to boys (8, 26). Our findings confirmed this tendency for girls to report worse life satisfaction over the years, with a widening gender gap observed in 2021. Regarding the effect of the pandemic on

mental health, results vary between studies. Vandentorren et al. (6) found that girls' mental health was more impacted by the pandemic in France, whereas Ravens-Sieberer et al. (2) found that in Germany, unlike in France, being a girl and older was a resource resilience factor, with fewer mental health problems. Adolescents from families from a lower socioeconomic background also appeared less likely to report high life satisfaction, as observed in other studies (27, 28). They may have had more often adverse experiences during the

<footnote><sup>a</sup>Unweighted count (Weighted %).</footnote>

<footnote><sup>b</sup>Chi-squared test with Rao & Scott's second-order correction.</footnote>
pandemic, such as food insecurity or a parent losing their job (29). Adverse childhood experiences were found to be associated with poorer mental health and suicidal behaviors during and after the

COVID-19 pandemic (29). Although it is known that parental unemployment is related to lower life satisfaction for adolescents (30), we did not find a relationship between parental employment and changes in life satisfaction during the pandemic. In line with several previous studies (31–33), in our study, adolescents with a chronic condition were less likely to report high satisfaction than those without a chronic condition (Figure 1), whatever the survey year (Supplementary Table S2). However, our findings did not suggest a greater impact of the pandemic on changes in life satisfaction among adolescents with chronic conditions compared to adolescents without chronic conditions. Similar results were found in Australia for adolescents with neurodevelopmental disorders by Houghton et al. (34), with differences depending on the individual diagnosis. For example, adolescents with attention-deficit/ hyperactivity disorder reported better well-being after school lockdown. Indeed, chronic conditions as a unique common category (i.e., without considering precise diagnosis nor the severity of the condition and its impact on schooling) could mask differences in the experience of school closures, specifically regarding working at home or being isolated from peers. For example, although not visible in

<figure><img src="image_4.png" /><figcaption>FIGURE 2
Cantril score distributions in 2020 (retrospective) and 2021.</figcaption></figure>

<table><caption>TABLE 4 Association between sample characteristics and March 2020 lockdown conditions with 2021–2020 changes in life satisfaction: multinomial logistic regression analysis.</caption><thead><tr><th rowspan="2"></th><th colspan="2">Decreased life satisfaction 2020–2021 vs. No change</th><th colspan="2">Improved life satisfaction 2020–2021 vs. No change</th></tr><tr><th>Adjusted OR<sup>a</sup> (95% CI)</th><th>p-value</th><th>Adjusted OR<sup>a</sup> (95% CI)</th><th>p-value</th></tr></thead><tbody><tr><td><strong>Sex</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Boy</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>Girl</td><td>1.43 (1.14–1.79)</td><td>0.003</td><td>1.82 (1.40–2.37)</td><td>&lt;0.001</td></tr><tr><td><strong>Educational delay in 2021</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>No</td><td>ref</td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>1.45 (0.98–2.12)</td><td>0.060</td><td>1.43 (1.00–2.04)</td><td>0.047</td></tr><tr><td><strong>Family structure in 2021</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Nuclear family</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>Single parents or others</td><td>1.58 (1.01–2.49)</td><td>0.046</td><td>1.51 (0.93–2.45)</td><td>0.092</td></tr><tr><td>Reconstructed family</td><td>2.09 (1.58–2.77)</td><td>&lt;0.001</td><td>1.19 (0.87–1.64)</td><td>0.272</td></tr><tr><td><strong>Parental employment in 2021</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Both parents employed</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>One parent employed</td><td>1.11 (0.77–1.60)</td><td>0.563</td><td>1.12 (0.78–1.60)</td><td>0.531</td></tr><tr><td>Both parents unemployed</td><td>1.77 (0.71–4.45)</td><td>0.220</td><td>1.38 (0.42–4.56)</td><td>0.598</td></tr><tr><td><strong>Having a chronic condition</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>No</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>Yes</td><td>1.26 (0.86–1.85)</td><td>0.235</td><td>0.88 (0.59–1.31)</td><td>0.517</td></tr><tr><td><strong>Have had their own room during the lockdown</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>No</td><td>1.58 (1.16–2.15)</td><td>0.001</td><td>1.16 (0.81–1.66)</td><td>0.361</td></tr><tr><td><strong>Have had access to an outdoor space during the lockdown</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>No</td><td>0.86 (0.55–1.32)</td><td>0.476</td><td>0.85 (0.55–1.31)</td><td>0.451</td></tr><tr><td><strong>Have had access to a screen to contact classmates or friends online during the lockdown</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>No</td><td>1.47 (1.09–1.98)</td><td>0.011</td><td>1.10 (0.73–1.67)</td><td>0.63</td></tr><tr><td><strong>Study conditions during the lockdown</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Bad study conditions</td><td>1.48 (0.99–2.21)</td><td>0.057</td><td>1.60 (0.97–2.63)</td><td>0.067</td></tr><tr><td>Neither good nor bad study conditions</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>Good study conditions</td><td>1.06 (0.74–1.51)</td><td>0.750</td><td>0.84 (0.56–1.27)</td><td>0.409</td></tr></tbody></table>

<footnote>ªAdjustment variables: sex, educational delay.</footnote>
pandemic, such as food insecurity or a parent losing their job (29). Adverse childhood experiences were found to be associated with poorer mental health and suicidal behaviors during and after the

COVID-19 pandemic (29). Although it is known that parental unemployment is related to lower life satisfaction for adolescents (30), we did not find a relationship between parental employment and changes in life satisfaction during the pandemic. In line with several previous studies (31–33), in our study, adolescents with a chronic condition were less likely to report high satisfaction than those without a chronic condition (Figure 1), whatever the survey year (Supplementary Table S2). However, our findings did not suggest a greater impact of the pandemic on changes in life satisfaction among adolescents with chronic conditions compared to adolescents without chronic conditions. Similar results were found in Australia for adolescents with neurodevelopmental disorders by Houghton et al. (34), with differences depending on the individual diagnosis. For example, adolescents with attention-deficit/ hyperactivity disorder reported better well-being after school lockdown. Indeed, chronic conditions as a unique common category (i.e., without considering precise diagnosis nor the severity of the condition and its impact on schooling) could mask differences in the experience of school closures, specifically regarding working at home or being isolated from peers. For example, although not visible in

<figure><img src="image_4.png" /><figcaption>FIGURE 2
Cantril score distributions in 2020 (retrospective) and 2021.</figcaption></figure>

<table><caption>TABLE 4 Association between sample characteristics and March 2020 lockdown conditions with 2021–2020 changes in life satisfaction: multinomial logistic regression analysis.</caption><thead><tr><th rowspan="2"></th><th colspan="2">Decreased life satisfaction 2020–2021 vs. No change</th><th colspan="2">Improved life satisfaction 2020–2021 vs. No change</th></tr><tr><th>Adjusted OR<sup>a</sup> (95% CI)</th><th>p-value</th><th>Adjusted OR<sup>a</sup> (95% CI)</th><th>p-value</th></tr></thead><tbody><tr><td><strong>Sex</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Boy</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>Girl</td><td>1.43 (1.14–1.79)</td><td>0.003</td><td>1.82 (1.40–2.37)</td><td>&lt;0.001</td></tr><tr><td><strong>Educational delay in 2021</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>No</td><td>ref</td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>1.45 (0.98–2.12)</td><td>0.060</td><td>1.43 (1.00–2.04)</td><td>0.047</td></tr><tr><td><strong>Family structure in 2021</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Nuclear family</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>Single parents or others</td><td>1.58 (1.01–2.49)</td><td>0.046</td><td>1.51 (0.93–2.45)</td><td>0.092</td></tr><tr><td>Reconstructed family</td><td>2.09 (1.58–2.77)</td><td>&lt;0.001</td><td>1.19 (0.87–1.64)</td><td>0.272</td></tr><tr><td><strong>Parental employment in 2021</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Both parents employed</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>One parent employed</td><td>1.11 (0.77–1.60)</td><td>0.563</td><td>1.12 (0.78–1.60)</td><td>0.531</td></tr><tr><td>Both parents unemployed</td><td>1.77 (0.71–4.45)</td><td>0.220</td><td>1.38 (0.42–4.56)</td><td>0.598</td></tr><tr><td><strong>Having a chronic condition</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>No</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>Yes</td><td>1.26 (0.86–1.85)</td><td>0.235</td><td>0.88 (0.59–1.31)</td><td>0.517</td></tr><tr><td><strong>Have had their own room during the lockdown</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>No</td><td>1.58 (1.16–2.15)</td><td>0.001</td><td>1.16 (0.81–1.66)</td><td>0.361</td></tr><tr><td><strong>Have had access to an outdoor space during the lockdown</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>No</td><td>0.86 (0.55–1.32)</td><td>0.476</td><td>0.85 (0.55–1.31)</td><td>0.451</td></tr><tr><td><strong>Have had access to a screen to contact classmates or friends online during the lockdown</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>No</td><td>1.47 (1.09–1.98)</td><td>0.011</td><td>1.10 (0.73–1.67)</td><td>0.63</td></tr><tr><td><strong>Study conditions during the lockdown</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Bad study conditions</td><td>1.48 (0.99–2.21)</td><td>0.057</td><td>1.60 (0.97–2.63)</td><td>0.067</td></tr><tr><td>Neither good nor bad study conditions</td><td>ref</td><td></td><td>ref</td><td></td></tr><tr><td>Good study conditions</td><td>1.06 (0.74–1.51)</td><td>0.750</td><td>0.84 (0.56–1.27)</td><td>0.409</td></tr></tbody></table>

<footnote>ªAdjustment variables: sex, educational delay.</footnote>
our current results, we would expect to observe greater life satisfaction among adolescents with chronic conditions during lockdown because these students are more often victims of bullying (14, 35). We can also hypothesize a decrease in face-to-face bullying in 2020, but an increase in cyber-bullying.

The factors related to the housing and schooling condition during the first COVID-19 lockdown did not differ between students with stable life satisfaction and those with better life satisfaction in 2021 compared to that declared regarding the 2020 lockdown. However, the proportion of students with lower life satisfaction in 2021 compared to that reported about the 2020 lockdown was higher among students not having their own room and not having access to a screen to contact classmates or friends online. Because of the alternating opening and closing of schools (lockdown, isolation in case of COVID-19), social contacts may have been either greatly diminished regarding peers while too important within the family (making it impossible for the adolescent to have a place of their own). Here, social networks may have had a protective role on adolescents' mental health by allowing them to stay connected to their peers. Indeed, Godeau et al. observed a decrease in bullying among adolescents in France during the pandemic (36), as well as a decrease in substance use (37), which can be interpreted as a consequence of the impossibility of accessing unsupervised interactions between peers (as well as limited access to substances).

## 4.3. Strengths and limitations

The main limitation of our study is related to the retrospective data collection of the 2020 Cantril score as well as the housing and studying conditions during the March 2020 lockdown, which could be prone to recall bias. Parental employment and family structure were measured in 2021 and could have changed between 2020 and 2021. Furthermore, some other factors related to parents were not measured in this study and may have had a differential impact on the life satisfaction of adolescents since the beginning of the pandemic (e.g., domestic violence (38), life satisfaction of parents (39)). Other confounding factors could explain the differences in the fluctuation of life satisfaction between girls and boys, such as the division of domestic tasks (6).

Our study has several strengths. The EnCLASS methodology is well established, and relies on longstanding methods validated internationally (40), which was not the case with many studies published during the pandemic (5, 41). The two-stage balanced cluster sampling method made the sample representative of metropolitan French last year of middle school students. In all these surveys, the participation rate of pupils in the participating classes was around 85%. When compared to data from the Ministry of Education, each sample was representative of the targeted students (in terms of type of municipality, public-private status, sex, age). In addition, for some survey waves, calibration weights were used to further improve representativeness. Moreover, our analyses allow us to measure life satisfaction from the direct point of view of adolescents. The Cantril ladder has been used the same way in the HBSC questionnaires since 2012, and its reliability and convergent validity for adolescents have been confirmed previously (8). This

allowed us to deepen and nuance the recent evolution of adolescents' perceived well-being and the impact of COVID-19 on adolescents' well-being, by putting it in a broader context.

## 4.4. Implications

Because the link between life satisfaction and mental health is no more to be questioned (42–44) and because the majority of mental disorders begin during adolescence (45), high-quality studies are needed to shed light on those and ensure mental health disorders are properly addressed by clinicians (46). Our results suggest that the identification of high-risk groups requires considering both clinical and socio-economic factors, including family structure, housing characteristics, and access to the internet. Monitoring trends in life satisfaction among adolescents can help anticipate and improve targeted prevention, screening, and medical follow-up for adolescents in need, particularly in crisis contexts such as pandemics. For example, the COVID-19 pandemic has been associated with unexpected changes in the epidemiology of adolescent suicidal behaviors in France (24, 25). However, previous studies examining such epidemiological trends were unable to evaluate the socio-economic factors that may explain the observed changes. Therefore, findings from large-scale and comprehensive studies on life satisfaction, such as the EnCLASS study, straighten the need to better support school health services, including after long periods of school absence (47). Furthermore, life satisfaction assessments offer an opportunity for pediatric and child health professionals to provide care services with a global approach of adolescents' health.

## 4.5. Conclusions

With a nationally representative sample and validated methods (compared to ad-hoc surveys), our study shows that the way French 14–15 years old adolescents experienced the first 2020 lockdown was not unequivocal, even if the majority reported no significant difference in their life satisfaction between 2020 and 2021. These results illustrate the complexity of measuring the impact of the pandemic on the health and well-being of adolescents, and the need to better understand associated factors. While the focus of this study was the changes between 2020 and 2021, more international research is needed to assess the long-term effect of the COVID-19 pandemic on adolescents in order to support them efficiently, even more if they belong to vulnerable groups. Such findings can help clinicians to identify adolescents at high risk of mental health problems in their practice. Our results should also help develop health promotion programs enhancing child well-being and life satisfaction.

## Data availability statement

The datasets presented in this article are not readily available because the data are made available upon request 3 years after
our current results, we would expect to observe greater life satisfaction among adolescents with chronic conditions during lockdown because these students are more often victims of bullying (14, 35). We can also hypothesize a decrease in face-to-face bullying in 2020, but an increase in cyber-bullying.

The factors related to the housing and schooling condition during the first COVID-19 lockdown did not differ between students with stable life satisfaction and those with better life satisfaction in 2021 compared to that declared regarding the 2020 lockdown. However, the proportion of students with lower life satisfaction in 2021 compared to that reported about the 2020 lockdown was higher among students not having their own room and not having access to a screen to contact classmates or friends online. Because of the alternating opening and closing of schools (lockdown, isolation in case of COVID-19), social contacts may have been either greatly diminished regarding peers while too important within the family (making it impossible for the adolescent to have a place of their own). Here, social networks may have had a protective role on adolescents' mental health by allowing them to stay connected to their peers. Indeed, Godeau et al. observed a decrease in bullying among adolescents in France during the pandemic (36), as well as a decrease in substance use (37), which can be interpreted as a consequence of the impossibility of accessing unsupervised interactions between peers (as well as limited access to substances).

## 4.3. Strengths and limitations

The main limitation of our study is related to the retrospective data collection of the 2020 Cantril score as well as the housing and studying conditions during the March 2020 lockdown, which could be prone to recall bias. Parental employment and family structure were measured in 2021 and could have changed between 2020 and 2021. Furthermore, some other factors related to parents were not measured in this study and may have had a differential impact on the life satisfaction of adolescents since the beginning of the pandemic (e.g., domestic violence (38), life satisfaction of parents (39)). Other confounding factors could explain the differences in the fluctuation of life satisfaction between girls and boys, such as the division of domestic tasks (6).

Our study has several strengths. The EnCLASS methodology is well established, and relies on longstanding methods validated internationally (40), which was not the case with many studies published during the pandemic (5, 41). The two-stage balanced cluster sampling method made the sample representative of metropolitan French last year of middle school students. In all these surveys, the participation rate of pupils in the participating classes was around 85%. When compared to data from the Ministry of Education, each sample was representative of the targeted students (in terms of type of municipality, public-private status, sex, age). In addition, for some survey waves, calibration weights were used to further improve representativeness. Moreover, our analyses allow us to measure life satisfaction from the direct point of view of adolescents. The Cantril ladder has been used the same way in the HBSC questionnaires since 2012, and its reliability and convergent validity for adolescents have been confirmed previously (8). This

allowed us to deepen and nuance the recent evolution of adolescents' perceived well-being and the impact of COVID-19 on adolescents' well-being, by putting it in a broader context.

## 4.4. Implications

Because the link between life satisfaction and mental health is no more to be questioned (42–44) and because the majority of mental disorders begin during adolescence (45), high-quality studies are needed to shed light on those and ensure mental health disorders are properly addressed by clinicians (46). Our results suggest that the identification of high-risk groups requires considering both clinical and socio-economic factors, including family structure, housing characteristics, and access to the internet. Monitoring trends in life satisfaction among adolescents can help anticipate and improve targeted prevention, screening, and medical follow-up for adolescents in need, particularly in crisis contexts such as pandemics. For example, the COVID-19 pandemic has been associated with unexpected changes in the epidemiology of adolescent suicidal behaviors in France (24, 25). However, previous studies examining such epidemiological trends were unable to evaluate the socio-economic factors that may explain the observed changes. Therefore, findings from large-scale and comprehensive studies on life satisfaction, such as the EnCLASS study, straighten the need to better support school health services, including after long periods of school absence (47). Furthermore, life satisfaction assessments offer an opportunity for pediatric and child health professionals to provide care services with a global approach of adolescents' health.

## 4.5. Conclusions

With a nationally representative sample and validated methods (compared to ad-hoc surveys), our study shows that the way French 14–15 years old adolescents experienced the first 2020 lockdown was not unequivocal, even if the majority reported no significant difference in their life satisfaction between 2020 and 2021. These results illustrate the complexity of measuring the impact of the pandemic on the health and well-being of adolescents, and the need to better understand associated factors. While the focus of this study was the changes between 2020 and 2021, more international research is needed to assess the long-term effect of the COVID-19 pandemic on adolescents in order to support them efficiently, even more if they belong to vulnerable groups. Such findings can help clinicians to identify adolescents at high risk of mental health problems in their practice. Our results should also help develop health promotion programs enhancing child well-being and life satisfaction.

## Data availability statement

The datasets presented in this article are not readily available because the data are made available upon request 3 years after
the data collection. Requests to access the datasets should be
directed to EG - emmanuelle.godeau@enclass.fr.

Ethics statement

The studies involving human participants were reviewed and
approved by French national council for statistical information
(CNIS). Written informed consent from the participants' legal
guardian was not required to participate in this study in
accordance with the national legislation and the institutional
requirements.

Author contributions

CH, VE, MS, and EG contributed to conception and design of the study. VE organized the database. CH and MS performed the statistical analysis. CH wrote the first draft of the manuscript. All authors contributed to the article and approved the submitted version.

Funding

ULYSSES: exchange travel funds allowing the conception of the first analysis and draft of the manuscript (PHC ULYSSES 47235UK).

References

1. Ravens-Sieberer U, Kaman A, Erhart M, Devine J, Schlack R, Otto C. Impact of the COVID-19 pandemic on quality of life and mental health in children and adolescents in Germany. *Eur Child Adolesc Psychiatry*. (2021) 31:879–89. doi: 10.1007/s00787-021-01726-5

2. Ravens-Sieberer U, Kaman A, Erhart M, Otto C, Devine J, Löffler C, et al. Quality of life and mental health in children and adolescents during the first year of the COVID-19 pandemic: results of a two-wave nationwide population-based study. *Eur Child Adolesc Psychiatry*. (2021) 32:575–88. doi: 10.1007/s00787-021-01889-1

3. Samji H, Wu J, Ladak A, Vossen C, Stewart E, Dove N, et al. Review: mental health impacts of the COVID-19 pandemic on children and youth—a systematic review. *Child Adolesc Ment Health*. (2022) 27(2):173–89. doi: 10.1111/camh.12501

4. Moore G. Mental health and life satisfaction among 10–11-year-olds in Wales, before and one year after onset of the COVID-19 pandemic. *BMC Public Health*. (2022) 22:379. doi: 10.1186/s12889-022-12752

5. Viner R, Russell S, Saulle R, Croker H, Stansfield C, Packer J, et al. School closures during social lockdown and mental health, health behaviors, and well-being among children and adolescents during the first COVID-19 wave: a systematic review. *JAMA Pediatr*. (2022) 176(4):400–9. doi: 10.1001/jamapediatrics.2021.5840

6. Vandentorren S. Premiers résultats des facteurs associés à la résilience et à la santé mentale des enfants et des adolescents (9–18 ans) lors du premier confinement lié à la COVID-19 en France/first results of factors associated with resilience and mental health of children and adolescents (9–18 years) during the first lockdown related to COVID-19 in France. BEH COVID-19. *Bull Epidémiol Hebd*. (2021) (Cov_8):2–17. http://beh.santepubliquefrance.fr/beh/2021/Cov_8/2021_Cov_8_1.htm

7. Lebrun-Harris LA, Ghandour RM, Kogan MD, Warren MD. Five-year trends in US children's health and well-being, 2016–2020. *JAMA Pediatr*. (2022) 176(7): e220056. doi: 10.1001/jamapediatrics.2022.0056

8. Levin KA, Currie C. Reliability and validity of an adapted version of the cantril ladder for use with adolescent samples. *Soc Indic Res*. (2014) 119(2):1047–63. doi: 10.1007/s11205-013-0507-4

Acknowledgments

The authors thank Nour Ibrahim for her precious proofreading and comments.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher's note

All claims expressed in this article are solely those of the
authors and do not necessarily represent those of their affiliated
organizations, or those of the publisher, the editors and the
reviewers. Any product that may be evaluated in this article, or
claim that may be made by its manufacturer, is not guaranteed
or endorsed by the publisher.

Supplementary material

The Supplementary Material for this article can be found
online at: https://www.frontiersin.org/articles/10.3389/fped.2023.
1204171/full#supplementary-material

9. Cantril H. *The pattern of human concerns*. New Brunswick, NJ: Rutgers University Press (1966). 898 p.

10. Mazur J, Szkultecka-Dębek M, Dzielska A, Drozd M, Małkowska-Szkutnik A. What does the Cantril Ladder measure in adolescence? *Aoms*. (2018) 1:182–9. doi: 10.5114/aoms.2016.60718

11. Inchley J, Currie D, Budisavljevic S, Torsheim T, Jåstad A, Cosma A, et al. *Spotlight on adolescent health and well-being. Findings from the 2017/2018 health behaviour in school-aged children (HBSC) survey in Europe and Canada. International report. Volume 1. Key findings*. Copenhagen: WHO Regional Office for Europe (2020).

12. The International HBSC Network Coordinating Committee, Currie C, Nic Gabhainn S, Godeau E. The health behaviour in school-aged children: wHO collaborative cross-national (HBSC) study: origins, concept, history and development 1982–2008. *Int J Public Health*. (2009) 54(S2):131–9. doi: 10.1007/s00038-009-5404-x

13. ESPAD Group. ESPAD 2019 Methodology: Methodology of the 2019 European school survey project on alcohol and other drugs. Luxembourg: Publications Office of the European Union (2021). (EMCDDA Joint Publications).

14. Sentenac M, Santos T, Augustine L, Michelsen SI, Movsesyan Y, Ng K, et al. Chronic health conditions and school experience in school-aged children in 19 European countries. *Eur Child Adolesc Psychiatry*. (2022) doi: 10.1007/s00787-022-01987-8

15. Marquez J, Long E. A global decline in adolescents' subjective well-being: a comparative study exploring patterns of change in the life satisfaction of 15-year-old students in 46 countries. *Child Ind Res*. (2021) 14(3):1251–92. doi: 10.1007/s12187-020-09788-8

16. Cavallo F, Dalmasso P, Ottová-Jordan V, Brooks F, Mazur J, Välimaa R, et al. Trends in life satisfaction in European and North-American adolescents from 2002 to 2010 in over 30 countries. *Eur J Public Health*. (2015) 25(suppl_2):80–2. doi: 10.1093/eurpub/ckv014
the data collection. Requests to access the datasets should be
directed to EG - emmanuelle.godeau@enclass.fr.

Ethics statement

The studies involving human participants were reviewed and
approved by French national council for statistical information
(CNIS). Written informed consent from the participants' legal
guardian was not required to participate in this study in
accordance with the national legislation and the institutional
requirements.

Author contributions

CH, VE, MS, and EG contributed to conception and design of the study. VE organized the database. CH and MS performed the statistical analysis. CH wrote the first draft of the manuscript. All authors contributed to the article and approved the submitted version.

Funding

ULYSSES: exchange travel funds allowing the conception of the first analysis and draft of the manuscript (PHC ULYSSES 47235UK).

References

1. Ravens-Sieberer U, Kaman A, Erhart M, Devine J, Schlack R, Otto C. Impact of the COVID-19 pandemic on quality of life and mental health in children and adolescents in Germany. *Eur Child Adolesc Psychiatry*. (2021) 31:879–89. doi: 10.1007/s00787-021-01726-5

2. Ravens-Sieberer U, Kaman A, Erhart M, Otto C, Devine J, Löffler C, et al. Quality of life and mental health in children and adolescents during the first year of the COVID-19 pandemic: results of a two-wave nationwide population-based study. *Eur Child Adolesc Psychiatry*. (2021) 32:575–88. doi: 10.1007/s00787-021-01889-1

3. Samji H, Wu J, Ladak A, Vossen C, Stewart E, Dove N, et al. Review: mental health impacts of the COVID-19 pandemic on children and youth—a systematic review. *Child Adolesc Ment Health*. (2022) 27(2):173–89. doi: 10.1111/camh.12501

4. Moore G. Mental health and life satisfaction among 10–11-year-olds in Wales, before and one year after onset of the COVID-19 pandemic. *BMC Public Health*. (2022) 22:379. doi: 10.1186/s12889-022-12752

5. Viner R, Russell S, Saulle R, Croker H, Stansfield C, Packer J, et al. School closures during social lockdown and mental health, health behaviors, and well-being among children and adolescents during the first COVID-19 wave: a systematic review. *JAMA Pediatr*. (2022) 176(4):400–9. doi: 10.1001/jamapediatrics.2021.5840

6. Vandentorren S. Premiers résultats des facteurs associés à la résilience et à la santé mentale des enfants et des adolescents (9–18 ans) lors du premier confinement lié à la COVID-19 en France/first results of factors associated with resilience and mental health of children and adolescents (9–18 years) during the first lockdown related to COVID-19 in France. BEH COVID-19. *Bull Epidémiol Hebd*. (2021) (Cov_8):2–17. http://beh.santepubliquefrance.fr/beh/2021/Cov_8/2021_Cov_8_1.htm

7. Lebrun-Harris LA, Ghandour RM, Kogan MD, Warren MD. Five-year trends in US children's health and well-being, 2016–2020. *JAMA Pediatr*. (2022) 176(7): e220056. doi: 10.1001/jamapediatrics.2022.0056

8. Levin KA, Currie C. Reliability and validity of an adapted version of the cantril ladder for use with adolescent samples. *Soc Indic Res*. (2014) 119(2):1047–63. doi: 10.1007/s11205-013-0507-4

Acknowledgments

The authors thank Nour Ibrahim for her precious proofreading and comments.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher's note

All claims expressed in this article are solely those of the
authors and do not necessarily represent those of their affiliated
organizations, or those of the publisher, the editors and the
reviewers. Any product that may be evaluated in this article, or
claim that may be made by its manufacturer, is not guaranteed
or endorsed by the publisher.

Supplementary material

The Supplementary Material for this article can be found
online at: https://www.frontiersin.org/articles/10.3389/fped.2023.
1204171/full#supplementary-material

9. Cantril H. *The pattern of human concerns*. New Brunswick, NJ: Rutgers University Press (1966). 898 p.

10. Mazur J, Szkultecka-Dębek M, Dzielska A, Drozd M, Małkowska-Szkutnik A. What does the Cantril Ladder measure in adolescence? *Aoms*. (2018) 1:182–9. doi: 10.5114/aoms.2016.60718

11. Inchley J, Currie D, Budisavljevic S, Torsheim T, Jåstad A, Cosma A, et al. *Spotlight on adolescent health and well-being. Findings from the 2017/2018 health behaviour in school-aged children (HBSC) survey in Europe and Canada. International report. Volume 1. Key findings.* Copenhagen: WHO Regional Office for Europe (2020).

12. The International HBSC Network Coordinating Committee, Currie C, Nic Gabhainn S, Godeau E. The health behaviour in school-aged children: wHO collaborative cross-national (HBSC) study: origins, concept, history and development 1982–2008. *Int J Public Health*. (2009) 54(S2):131–9. doi: 10.1007/s00038-009-5404-x

13. ESPAD Group. ESPAD 2019 Methodology: Methodology of the 2019 European school survey project on alcohol and other drugs. Luxembourg: Publications Office of the European Union (2021). (EMCDDA Joint Publications).

14. Sentenac M, Santos T, Augustine L, Michelsen SI, Movsesyan Y, Ng K, et al. Chronic health conditions and school experience in school-aged children in 19 European countries. *Eur Child Adolesc Psychiatry*. (2022) doi: 10.1007/s00787-022-01987-8

15. Marquez J, Long E. A global decline in adolescents' subjective well-being: a comparative study exploring patterns of change in the life satisfaction of 15-year-old students in 46 countries. *Child Ind Res*. (2021) 14(3):1251–92. doi: 10.1007/s12187-020-09788-8

16. Cavallo F, Dalmasso P, Ottová-Jordan V, Brooks F, Mazur J, Välimaa R, et al. Trends in life satisfaction in European and North-American adolescents from 2002 to 2010 in over 30 countries. *Eur J Public Health*. (2015) 25(suppl_2):80–2. doi: 10.1093/eurpub/ckv014
17. Mokkink LB, van der Lee JH, Grootenhuis MA, Offringa M, Heymans HSA. The dutch national consensus committee "chronic diseases and health conditions in childhood". defining chronic diseases and health conditions in childhood (0-18 years of age): national consensus in The Netherlands. *Eur J Pediatr.* (2008) 167 (12):1441-7. doi: 10.1007/s00431-008-0697-y

18. Torsheim T, Cavallo F, Levin KA, Schnohr C, Mazur J, Niclasen B, et al. Psychometric validation of the revised family affluence scale: a latent variable approach. *Child Indic Res.* (2016) 9:771-84. doi: 10.1007/s12187-015-9339-x

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22. Armocida B, Monasta L, Sawyer S, Bustreo F, Segafredo G, Castelpietra G, et al. Burden of non-communicable diseases among adolescents aged 10-24 years in the EU, 1990-2019: a systematic analysis of the global burden of diseases study 2019. *Lancet Child Adolesc Health.* (2022) 6(6):367-83. doi: 10.1016/S2352-4642(22) 00073-6

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24. Cousien A, Acquaviva E, Kernéis S, Yazdanpanah Y, Delorme R. Temporal trends in suicide attempts among children in the decade before and during the COVID-19 pandemic in Paris, France. *JAMA Netw Open.* (2021) 4(10):e2128611. doi: 10.1001/jamanetworkopen.2021.28611

25. Mourouvaye M, Bottemanne H, Bonny G, Fourcade L, Angoulvant F, Cohen JF, et al. Association between suicide behaviours in children and adolescents and the COVID-19 lockdown in Paris, France: a retrospective observational study. *Arch Dis Child.* (2021) 106(9):918-9. doi: 10.1136/archdischild-2020-320628

26. Due P, Eriksson C, Torsheim T, Potrebny T, Välimaa R, Suominen S, et al. Trends in high life satisfaction among adolescents in five Nordic countries 2002-2014. *Nord Välfärsforskning | Nordic Welfare Res.* (2019) 4(2):54-66. doi: 10.18261/issn.2464-4161-2019-02-03

27. Chzhen Y, Moor I, Pickett W, Stevens GWJM. Family Affluence and Inequality in Adolescent Health and Life Satisfaction: Evidence from the HBSC study 2002-2014. Innocenti Working Papers. (2016).

28. Hammami N, Erdoğan Y, Elgar FJ. Socioeconomic position mediates the relationship between family social benefits and adolescent life satisfaction in 25 countries. *Child Ind Res.* (2022) 15(5):1761-75. doi: 10.1007/s12187-022-09929-1

29. Anderson KN, Swedo EA, Trinh E, Ray CM, Krause KH, Verlenden JV, et al. Adverse childhood experiences during the COVID-19 pandemic and associations with poor mental health and suicidal behaviors among high school students — adolescent behaviors and experiences survey, United States, January–June 2021. *MMWR Morb Mortal Wkly Rep.* (2022) 71(41):1301-5. doi: 10.15585/mmwr.mm7141a2

30. Johansson K, Petersen S, Högberg B, Stevens GWJM, De Clercq B, Frasquilho D, et al. The interplay between national and parental unemployment in relation to adolescent life satisfaction in 27 countries: analyses of repeated cross-sectional school surveys. *BMC Public Health.* (2019) 19(1):1555. doi: 10.1186/s12889-019-7721-1

31. Cerqueira A, Gaspar T, Botelho Guedes F, Godeau E, Gaspar de Matos M. Chronic conditions, school participation and quality of life of Portuguese adolescents: highlights from the health behavior in school aged children study - HBSC 2018. *Child Ind Res.* (2022) 15(1):297-313. doi: 10.1007/s12187-021-09868-3

32. Berkelbach van der Sprenkel EE, Nijhof SL, Dalmeijer GW, Onland-Moret NC, de Roos SA, Lesscher HMB, et al. Psychosocial functioning in adolescents growing up

with chronic disease: the Dutch HBSC study. *Eur J Pediatr.* (2022) 181(2):763-73. doi: 10.1007/s00431-021-04268-9

33. Wagner G, Karwautz A, Philipp J, Truttmann S, Dür W, Waldherr K, et al. Mental health and health-related quality of life in Austrian adolescents with chronic physical health conditions: results from the MHAT study. *J Clin Med.* (2023) 12(5):1927. doi: 10.3390/jcm12051927

34. Houghton S, Kyron M, Lawrence D, Hunter SC, Hattie J, Carroll A, et al. Longitudinal trajectories of mental health and loneliness for Australian adolescents with or-for-without neurodevelopmental disorders: the impact of COVID-19 school lockdowns. *J Child Psychol Psychiatry.* (2022) 63(11):1332-43. doi: 10.1111/jcpp.13579

35. Sentenac M, Gavin A, Arnaud C, Molcho M, Godeau E, Gabhainn SN. Victims of bullying among students with a disability or chronic illness and their peers: a cross-national study between Ireland and France. *J Adolesc Health.* (2011) 48(5):461-6. doi: 10.1016/j.jadohealth.2010.07.031

36. Godeau E, Sentenac M, Hurel C, Ehlinger V. Enquêtes par auto-questionnaire au service de la santé à l'école: EnCLASS, un exemple français. *Rev Int D'éducation de Sèvres.* (2022) 89(89):149-58. doi: 10.4000/ries.12528

37. Spilka S, Philippon A, Nézet OL, Janssen E, Brissot A, Eroukmanoff V, et al. Alcohol, tobacco and cannabis use among ninth grade students (14-15-year-olds) in 2021. Tendances n°148 [English version]. (2021).

38. Kourti A, Stavridou A, Panagouli E, Psaltopoulou T, Spiliopoulou C, Tsolia M, et al. Domestic violence during the COVID-19 pandemic: a systematic review. *Trauma Violence Abuse.* (2023) 24(2):719-45. doi: 10.1177/15248380211038690

39. Schnettler B, Concha-Salgado A, Orellana L, Saracostti M, Miranda-Zapata E, Poblete H, et al. Revisiting the link between domain satisfaction and life satisfaction during the COVID-19 pandemic: job-related moderators in triadic analysis in dual-earner parents with adolescent children. *Front Public Health.* (2023) 11:1108336. doi: 10.3389/fpubh.2023.1108336

40. Moor I, Winter K, Bilz L, Bucksch J, Finne E, John N, et al. The 2017/18 health behaviour in school-aged children (HBSC) study—methodology of the world health organization's child and adolescent health study. *J Health Monit.* (2020) 5(3):88-102. doi: 10.25646/6904

41. Manchia M, Gathier AW, Yapici-Eser H, Schmidt MV, de Quervain D, van Amelsvoort T, et al. The impact of the prolonged COVID-19 pandemic on stress resilience and mental health: a critical review across waves. *Eur Neuropsychopharmacol.* (2022) 55:22-83. doi: 10.1016/j.euroneuro.2021.10.864

42. Hawkins WE, Hawkins MJ, Seeley J. Stress, health-related behavior and quality of life on depressive symptomatology in a sample of adolescents. *Psychol Rep.* (1992) 71:183-6. doi: 10.2466/pr.1992.71.1.183

43. Bray I, Gunnell D. Suicide rates, life satisfaction and happiness as markers for population mental health. *Soc Psychiatry Psychiatr Epidemiol.* (2006) 41(5):333-7. doi: 10.1007/s00127-006-0049-z

44. Lombardo P, Jones W, Wang L, Shen X, Goldner EM. The fundamental association between mental health and life satisfaction: results from successive waves of a Canadian national survey. *BMC Public Health.* (2018) 18(1):342. doi: 10.1186/s12889-018-5235-x

45. Goldbeck L, Schmitz TG, Besier T, Herschbach P, Henrich G. Life satisfaction decreases during adolescence. *Qual Life Res.* (2007) 16:969-79. doi: 10.1007/s11136-007-9205-5

46. Carvajal-Velez L, Harris Requejo J, Ahs JW, Idele P, Adewuya A, Cappa C, et al. Increasing data and understanding of adolescent mental health worldwide: UNICEF's measurement of mental health among adolescents at the population level initiative. *J Adolesc Health.* (2023) 72(1S):S12-4. doi: 10.1016/j.jadohealth.2021.03.019

47. Michaud PA, Vervoort JPM, Visser A, Baltag V, Reijneveld SA, Kocken PL, et al. Organization and activities of school health services among EU countries. *Eur J Public Health.* (2021) 31(3):502-8. doi: 10.1093/eurpub/ckaa200
17. Mokkink LB, van der Lee JH, Grootenhuis MA, Offringa M, Heymans HSA. The dutch national consensus committee "chronic diseases and health conditions in childhood". defining chronic diseases and health conditions in childhood (0-18 years of age): national consensus in The Netherlands. *Eur J Pediatr.* (2008) 167 (12):1441-7. doi: 10.1007/s00431-008-0697-y

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19. Currie C, Molcho M, Boyce W, Holstein B, Torsheim T, Richter M. Researching health inequalities in adolescents: the development of the health behaviour in school-aged children (HBSC) family affluence scale. *Soc Sci Med.* (2008) 66(6):1429-36. doi: 10.1016/j.socscimed.2007.11.024

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22. Armocida B, Monasta L, Sawyer S, Bustreo F, Segafredo G, Castelpietra G, et al. Burden of non-communicable diseases among adolescents aged 10-24 years in the EU, 1990-2019: a systematic analysis of the global burden of diseases study 2019. *Lancet Child Adolesc Health.* (2022) 6(6):367-83. doi: 10.1016/S2352-4642(22) 00073-6

23. Nearchou F, Flinn C, Niland R, Subramaniam SS, Hennessy E. Exploring the impact of COVID-19 on mental health outcomes in children and adolescents: a systematic review. *IJERPH.* (2020) 17(22):8479. doi: 10.3390/ijerph17228479

24. Cousien A, Acquaviva E, Kernéis S, Yazdanpanah Y, Delorme R. Temporal trends in suicide attempts among children in the decade before and during the COVID-19 pandemic in Paris, France. *JAMA Netw Open.* (2021) 4(10):e2128611. doi: 10.1001/jamanetworkopen.2021.28611

25. Mourouvaye M, Bottemanne H, Bonny G, Fourcade L, Angoulvant F, Cohen JF, et al. Association between suicide behaviours in children and adolescents and the COVID-19 lockdown in Paris, France: a retrospective observational study. *Arch Dis Child.* (2021) 106(9):918-9. doi: 10.1136/archdischild-2020-320628

26. Due P, Eriksson C, Torsheim T, Potrebny T, Välimaa R, Suominen S, et al. Trends in high life satisfaction among adolescents in five Nordic countries 2002-2014. *Nord Välfärsforskning | Nordic Welfare Res.* (2019) 4(2):54-66. doi: 10.18261/issn.2464-4161-2019-02-03

27. Chzhen Y, Moor I, Pickett W, Stevens GWJM. Family Affluence and Inequality in Adolescent Health and Life Satisfaction: Evidence from the HBSC study 2002-2014. Innocenti Working Papers. (2016).

28. Hammami N, Erdoğan Y, Elgar FJ. Socioeconomic position mediates the relationship between family social benefits and adolescent life satisfaction in 25 countries. *Child Ind Res.* (2022) 15(5):1761-75. doi: 10.1007/s12187-022-09929-1

29. Anderson KN, Swedo EA, Trinh E, Ray CM, Krause KH, Verlenden JV, et al. Adverse childhood experiences during the COVID-19 pandemic and associations with poor mental health and suicidal behaviors among high school students — adolescent behaviors and experiences survey, United States, January–June 2021. *MMWR Morb Mortal Wkly Rep.* (2022) 71(41):1301-5. doi: 10.15585/mmwr.mm7141a2

30. Johansson K, Petersen S, Högberg B, Stevens GWJM, De Clercq B, Frasquilho D, et al. The interplay between national and parental unemployment in relation to adolescent life satisfaction in 27 countries: analyses of repeated cross-sectional school surveys. *BMC Public Health.* (2019) 19(1):1555. doi: 10.1186/s12889-019-7721-1

31. Cerqueira A, Gaspar T, Botelho Guedes F, Godeau E, Gaspar de Matos M. Chronic conditions, school participation and quality of life of Portuguese adolescents: highlights from the health behavior in school aged children study - HBSC 2018. *Child Ind Res.* (2022) 15(1):297-313. doi: 10.1007/s12187-021-09868-3

32. Berkelbach van der Sprenkel EE, Nijhof SL, Dalmeijer GW, Onland-Moret NC, de Roos SA, Lesscher HMB, et al. Psychosocial functioning in adolescents growing up

with chronic disease: the Dutch HBSC study. *Eur J Pediatr.* (2022) 181(2):763-73. doi: 10.1007/s00431-021-04268-9

33. Wagner G, Karwautz A, Philipp J, Truttmann S, Dür W, Waldherr K, et al. Mental health and health-related quality of life in Austrian adolescents with chronic physical health conditions: results from the MHAT study. *J Clin Med.* (2023) 12 (5):1927. doi: 10.3390/jcm12051927

34. Houghton S, Kyron M, Lawrence D, Hunter SC, Hattie J, Carroll A, et al. Longitudinal trajectories of mental health and loneliness for Australian adolescents with or-for-without neurodevelopmental disorders: the impact of COVID-19 school lockdowns. *J Child Psychol Psychiatry.* (2022) 63(11):1332-43. doi: 10.1111/jcpp.13579

35. Sentenac M, Gavin A, Arnaud C, Molcho M, Godeau E, Gabhainn SN. Victims of bullying among students with a disability or chronic illness and their peers: a cross-national study between Ireland and France. *J Adolesc Health.* (2011) 48(5):461-6. doi: 10.1016/j.jadohealth.2010.07.031

36. Godeau E, Sentenac M, Hurel C, Ehlinger V. Enquêtes par auto-questionnaire au service de la santé à l'école: EnCLASS, un exemple français. *Rev Int D'éducation de Sèvres.* (2022) 89(89):149-58. doi: 10.4000/ries.12528

37. Spilka S, Philippon A, Nézet OL, Janssen E, Brissot A, Eroukmanoff V, et al. Alcohol, tobacco and cannabis use among ninth grade students (14-15-year-olds) in 2021. Tendances n°148 [English version]. (2021).

38. Kourti A, Stavridou A, Panagouli E, Psaltopoulou T, Spiliopoulou C, Tsolia M, et al. Domestic violence during the COVID-19 pandemic: a systematic review. *Trauma Violence Abuse.* (2023) 24(2):719-45. doi: 10.1177/15248380211038690

39. Schnettler B, Concha-Salgado A, Orellana L, Saracostti M, Miranda-Zapata E, Poblete H, et al. Revisiting the link between domain satisfaction and life satisfaction during the COVID-19 pandemic: job-related moderators in triadic analysis in dual-earner parents with adolescent children. *Front Public Health.* (2023) 11:1108336. doi: 10.3389/fpubh.2023.1108336

40. Moor I, Winter K, Bilz L, Bucksch J, Finne E, John N, et al. The 2017/18 health behaviour in school-aged children (HBSC) study—methodology of the world health organization's child and adolescent health study. *J Health Monit.* (2020) 5 (3):88-102. doi: 10.25646/6904

41. Manchia M, Gathier AW, Yapici-Eser H, Schmidt MV, de Quervain D, van Amelsvoort T, et al. The impact of the prolonged COVID-19 pandemic on stress resilience and mental health: a critical review across waves. *Eur Neuropsychopharmacol.* (2022) 55:22-83. doi: 10.1016/j.euroneuro.2021.10.864

42. Hawkins WE, Hawkins MJ, Seeley J. Stress, health-related behavior and quality of life on depressive symptomatology in a sample of adolescents. *Psychol Rep.* (1992) 71:183-6. doi: 10.2466/pr.1992.71.1.183

43. Bray I, Gunnell D. Suicide rates, life satisfaction and happiness as markers for population mental health. *Soc Psychiatry Psychiatr Epidemiol.* (2006) 41(5):333-7. doi: 10.1007/s00127-006-0049-z

44. Lombardo P, Jones W, Wang L, Shen X, Goldner EM. The fundamental association between mental health and life satisfaction: results from successive waves of a Canadian national survey. *BMC Public Health.* (2018) 18(1):342. doi: 10.1186/s12889-018-5235-x

45. Goldbeck L, Schmitz TG, Besier T, Herschbach P, Henrich G. Life satisfaction decreases during adolescence. *Qual Life Res.* (2007) 16:969-79. doi: 10.1007/s11136-007-9205-5

46. Carvajal-Velez L, Harris Requejo J, Ahs JW, Idele P, Adewuya A, Cappa C, et al. Increasing data and understanding of adolescent mental health worldwide: UNICEF's measurement of mental health among adolescents at the population level initiative. *J Adolesc Health.* (2023) 72(1S):S12-4. doi: 10.1016/j.jadohealth.2021.03.019

47. Michaud PA, Vervoort JPM, Visser A, Baltag V, Reijneveld SA, Kocken PL, et al. Organization and activities of school health services among EU countries. *Eur J Public Health.* (2021) 31(3):502-8. doi: 10.1093/eurpub/ckaa200