Different Categories of Social Media Use and Their Association With Body Image Among Adolescents in 42 Countries.

Objectives: Social media has become integrated into adolescents' lives and influences body image perceptions. Our study examined four patterns of social media use (SMU): non-active, active, intensive, and problematic. We hypothesised that intensive SMU and problematic SMU would be associated with negative body image (negative subjective body weight) and over/underestimated body weight congruence, compared to non-active and active SMU. In addition, we expect these associations to be stronger for girls. Methods: Data from 190,892 respondents aged 11, 13, and 15 from 42 countries involved in the Health Behaviour in School-aged Children study were analysed. Results: Findings revealed higher rates of intensive or problematic SMU among adolescents who perceived themselves as too fat or too thin. Two-level regression analyses showed intensive and problematic SMU as more likely to perceive themselves as too fat or too thin than active users. The association was significant among intensive and problematic girl social media users, whereas, among boys, the relationship was only significant for problematic users. Conclusion: Our findings highlight the importance of assessing SMU patterns to evaluate associations with body image.

Adolescents perception of the COVID-19 pandemic restrictions and associated mental health and well-being: gender, age and socioeconomic differences in 22 countries.

BACKGROUND: The COVID-19-pandemic has had a profound impact on the lives of adolescents worldwide. This study examined the subjective perception of the COVID-19 pandemic measures and its association with mental health and well-being (i.e., loneliness, life satisfaction and multiple health complaints) among 13- and 15-years-old adolescents from 22 countries. METHODS: Data from the cross-national Health Behaviour in School-aged Children (HBSC) 2021/22 study were used from representative samples of 22 countries (N = 67,544; 51.9% girls). The self-perceived impact of COVID-19 measure comprised 10 items asking about the impact on several dimensions of adolescent lives (e.g., relationships with family and friends, health, or eating behaviours). Measures of loneliness, multiple health complaints, and life satisfaction were included as indicators of mental health and well-being. A non-parametric multilevel latent class analysis considering individual and country-levels was conducted to identify classes of self-perceived impact of the COVID-19 measures. Multilevel logistic regression models adjusted by age and socioeconomic status were applied to assess the association between COVID-19 measure impact classes and mental health. RESULTS: Three classes were identified on individual level encompassing a neutral (51%), positive (31%), or negative (18%) perception of COVID-19 measures. A third of the adolescents reported a positive impact of the pandemic measures. The distribution of classes was heterogeneous within and across countries. Within the positive COVID-19 measure impact class, social relationships were the most important dimension, whereas mental health problems were mostly represented within the negative COVID-19 measure impact class. Girls with a negative perception of pandemic measures showed higher levels of loneliness and multiple health complaints and lower life satisfaction. 15-year-old adolescents and those with a low socioeconomic status reported higher levels of loneliness and lower life satisfaction. CONCLUSIONS: The majority of adolescents perceived the pandemic measures as neutral or positive. Girls, 15-year-old adolescents, and those with low socioeconomic status were at higher risk of suffering from pandemic measures and associated problems of loneliness, multiple health complaints, and low life satisfaction. We conclude that adolescent's mental health and well-being should be considered in the decision-making process by ensuring that the unique challenges of adolescents are adequately addressed in policies.

Seeing haemoglobin SC: Challenging the misperceptions.

Historically understudied and regarded as a mild type of sickle cell disease, HbSC can be associated with significant, progressive complications. Prospective studies are urgently needed to address treatment gaps for HbSC disease. Commentary on: Nelson et al. The clinical spectrum of HbSC sickle cell disease-not a benign condition. Br J Haematol 2024 (Online ahead of print). doi: 10.1111/bjh.19523.

The clinical spectrum of HbSC sickle cell disease-not a benign condition.

Sickle cell disease (SCD) includes a group of heterogenous disorders that result in significant morbidities. HbSS is the most common type of SCD and HbSC is the second most common type of SCD. The prevalence of HbSC disease in the United States and United Kingdom is ~1 in 7174 births and 1 in 6174 births respectively. Despite its frequency, however, HbSC disease has been insufficiently studied and was historically categorized as a more 'mild' form of SCD. We conducted this study of HbSC disease as part of the NHLBI funded Sickle Cell Disease Implementation Consortium (SCDIC). The SCDIC registry included 2282 individuals with SCD, ages 15-45 years of whom 502 (22%) had HbSC disease. Compared with people with sickle cell anaemia (SCA), the study found that people with HbSC disease had a higher frequency of splenomegaly (n (%) = 169 (33.7) vs. 392 (22.1)) and retinopathy (n (%) = 116 (23.1) vs. 189 (10.6)). A Many people with HbSC also had avascular necrosis (n (%) = 112 (22.3)), pulmonary embolism (n (%) = 43 (8.6)) and acute chest syndrome (n (%) = 228 (45.4)) demonstrating significant disease severity. HbSC disease is more clinically severe than was previously recognized and deserves additional evaluation and targeted treatments.

Intense and problematic social media use and sleep difficulties of adolescents in 40 countries.

INTRODUCTION: Social media has become a ubiquitous part of everyday life; however, evidence suggests patterns of social media use can affect sleep health in children and adolescents. This study aimed to examine the associations of intense and problematic social media use (SMU) with sleep-onset difficulties in adolescence. METHODS: We analysed data from 212,613 adolescents aged 11-15 years (51.1% girls) from 40 European and North American countries that participated in the 2017/2018 Health Behaviour in School-aged Children survey. Intense SMU assessed how often respondents had online contact through social media, and problematic SMU was assessed by symptoms of addiction to social media. Sleep-onset difficulties were assessed using a self-reported item. Multilevel mixed-effects logistic regression was used to obtain the estimates. RESULTS: Sleep-onset difficulties were more common among girls than boys (27.1% vs 20.8%). Intense SMU was significantly associated with sleep-onset difficulties in boys in 17 countries and in girls in 25 countries, while problematic SMU was significantly associated in most of the participating countries. Overall, exposure to problematic SMU alone was highly associated with sleep-onset difficulties both in girls (OR 2.20, 2.04-2.38) and boys (OR 1.88, 1.73-2.04), while the association estimates for intense SMU were smaller and comparable across gender (Girls: OR 1.27, 1.23-1.31; Boys: OR 1.22, 1.18-1.27). Sensitivity analyses supported the above findings. CONCLUSIONS: Intense and/or problematic SMU were associated with sleep-onset difficulties across gender with associations being higher for problematic compared to intense SMU. Prospective research with objective measures is needed to understand the causal mechanisms underlying these relationships.

SARS-CoV-2 with Influenza B Coinfection in a Patient with Sickle Cell HbSC Presenting with Painful Crisis: A Case Report.

Sickle cell disease is a hereditary red blood cell disorder characterized by hemolytic anemia, particularly in association with stress. As they grow, most children with sickle cell anemia undergo auto-splenectomy, making them vulnerable to serious infections. Patients with sickle cell disease infected with the SARS-CoV-2 virus are reported to have an increased risk for hospitalization, thrombosis, and other complications compared to non-sickle cell patients. Influenza infection in patients with sickle cell is associated with increased morbidity. Patients with sickle cell HbSC are reported to have a milder form of the disease than HbSS. Coinfection with SARS-CoV-2 and influenza B is rarely reported in patients with hematologic diseases, including sickle cell hemoglobinopathy. We are reporting an unusual case of a patient with sickle cell HbSC with co-infection of SARS-CoV-2 and influenza B with a favorable outcome.

Associations Between Recent Contraceptive Use and First Sex Behaviors of Scottish Adolescents: A Brief Report.

Objectives: We examined associations between recent contraceptive use and first-sex behaviors (early initiation, substance use, contraceptive use) among adolescents in Scotland. Methods: We used data from the Health Behavior in School-aged Children study. Results: Controlling for early initiation and substance use, girls and boys who used contraceptives at first sex were 7.5 and 12.3 times more likely to use contraceptives at most recent sexual intercourse than adolescents who did not (p < .001). We also present preliminary evidence on contraceptive use of Scottish adolescents in 2022. Conclusions: Experiences during adolescents' first sex may have lasting implications for later sexual behavior.

Bullying at School, Cyberbullying, and Loneliness: National Representative Study of Adolescents in Denmark.

AIMS: The aim was to examine how loneliness was associated with bullying victimization at school and online. METHODS: We used data from the Danish arm of the international Health Behavior in School-aged Children (HBSC) study from 2022. The study population was a nationally representative sample of 11-15-year-olds who completed the internationally standardized HBSC questionnaire at school, n = 5382. Multilevel logistic regression was applied to study the associations between bullying victimization and loneliness. RESULTS: The prevalence of reporting loneliness often or very often was 9.0%; 6.3% of the sample experienced habitual bullying victimization at school, and 4.8% incurred cyberbullying. There was a strong and graded association between loneliness and bullying victimization at school and cyberbullying. The associations were significant for boys and girls, and the association between exposure to bullying at school and loneliness was steeper for boys than girls. The gradients were steeper for physical bullying than for cyberbullying. Students exposed to habitual bullying in both contexts had an adjusted OR (95% CI) of 11.21 (6.99-17.98) for loneliness. CONCLUSION: Exposure to bullying at school and cyberbullying are strongly associated with loneliness. It is important to reduce bullying at school and on the internet and to promote effective interventions to reduce continuing loneliness.

Physical activity of older children and adolescents in Germany - Results of the HBSC study 2022 and trends since 2009/10.

Background: Physical activity is central to health, beginning in childhood and adolescence, and regular monitoring provides important information for strategic decisions on promoting physical activity in Germany. Methods: The current survey cycle of the Health Behaviour in School-aged Children (HBSC) study gives an insight into the prevalence of the indicators daily recommended physical activity, high and low physical activity, and sporting activity among students aged between 11 and 15 for 2022. In addition, the data is compared to the survey cycles of the 2009/10, 2013/14, and 2017/18 school years and analysed over time. Results: The results of the current survey cycle show that 10.8 % of girls, 20.9 % of boys, and 12.4 % of gender diverse adolescents fulfil the daily physical activity recommendation. There are also major gender-specific differences for the other indicators. The group of gender diverse adolescents needs to be analysed further. The changes over time between 2009/10 and 2022 are relatively small. While girls' physical activity habits decreased slightly for the various indicators between 2009/10 and 2022, boys' prevalence remained relatively stable over the same period. Conclusions: Overall, in part due to the effects of the various COVID-19 lockdowns, the need for effective and population-based measures to promote physical activity in childhood and adolescence remains high.

Traditional bullying and cyberbullying at schools in Germany: Results of the HBSC study 2022 and trends from 2009/10 to 2022.

Background: Bullying is a form of violence that is carried out repeatedly, with the intention of causing harm and with an imbalance of power between those involved. Bullying has serious negative effects on the mental health of adolescents and thus represents a significant health risk in childhood and adolescence. Methods: Based on data from the Health Behaviour in School-aged Children (HBSC) study from the survey year 2022 in Germany (N = 6,475), the prevalence of school bullying and cyberbullying among 11-, 13- and 15-year-olds in Germany was analysed. In addition, the prevalence of school bullying and cyberbullying was analysed as a trend from 2009/10 to 2022 (bullying) and from 2017/18 to 2022 (cyberbullying). Results: Around 14 % of the learners surveyed reported direct experience of bullying at school, and around 7 % reported cyberbullying experiences as bullied and/or bullying victims. Adolescents who identified as gender diverse were particularly likely to report bullying experiences. School bullying decreased over time, but remained stable between 2017/18 and 2022. Cyberbullying, on the other hand, increased in 2022 compared to 2017/18. Conclusions: Experiencing bullying at school and online is an everyday experience for many children and young people, so there is still a need for the broad implementation of effective anti-bullying measures in schools.

Trends in health inequalities in childhood and adolescence in Germany: Results of the HBSC study 2009/10 - 2022.

Background: Many studies have identified health inequalities in childhood and adolescence. However, it is unclear how these have developed in recent years, particularly since the COVID-19 pandemic. Methods: Analyses are based on the German data from the international Health Behaviour in School-aged Children (HBSC) study from 2009/10 (n = 5,005), 2013/14 (n = 5,961), 2017/18 (n = 4,347), and 2022 (n = 6,475). A total of 21,788 students aged approximately between 11 and 15 years were included. Socioeconomic status (SES) was assessed using the Family Affluence Scale (FAS). Several health indicators were analysed stratified by gender using bivariate and multivariate analysis methods. Results: In 2022, there are clear socioeconomic inequalities in life satisfaction, self-rated health, fruit and vegetable consumption, and physical activity. These inequalities remained largely constant or increased between 2009/10 and 2022. Between 2017/18 and 2022, no significant changes in inequalities were found. Conclusions: Health inequalities are persistent and reduce the chances of growing up healthy. There is no evidence that inequalities in the analysed outcomes have changed during the pandemic period (between 2017/18 and 2022). Rather, the changes in the health indicators seem to affect all adolescents in a similar way.

Health literacy of students in Germany - Results of the HBSC study 2022.

Background: Health literacy (HL) encompasses knowledge and skills for dealing critically and confidently with health information in individual and social contexts. Current studies show that a high proportion of children and adolescents have limited health literacy, depending on aspects of their social background. Health literacy is considered an important factor influencing health. Little is known about the development of health literacy over time and its connection with psychosomatic complaints in young people. Methods: Based on the results of the Health Behaviour in School-aged Children (HBSC) study, this article focusses on the level of HL in 11-, 13-, and 15-year-old students (N = 6,475) over time and taking social differences into account. Finally, the relationship between HL and psychosomatic complaints is analysed. Univariate, bivariate, and multivariate analyses were carried out for this purpose. Results: At 24.4 %, slightly more students have low HL in 2022 than in 2017/18 (21.4 %). There are differences in HL according to gender, age, type of school, and family affluence. Low HL is associated with a high psychosomatic burden. Conclusions: The results highlight the need for target group-specific measures to promote young people's HL, which address individual and organisational aspects of HL.

Concept and methodology of the Health Behaviour in School-aged Children (HBSC) study - Insights into the current 2022 survey and trends in Germany.

Background: Health Behaviour in School-aged Children (HBSC) is one of the largest international studies on child and adolescent health and cooperates with the World Health Organization (WHO). In Germany, adolescents aged 11, 13 and 15 are surveyed every four years about their health, health behaviour and social conditions. This article describes the HBSC study and in particular the methodology of the current 2022 survey and prior surveys conducted between 2009/10 and 2017/18. Method: 174 schools with a total of 6,475 students participated in the 2022 survey. The survey was conducted using questionnaires and covered a wide range of topics (including mental health, physical activity, bullying experiences, social determinants of health and experiences related to COVID-19). The 2022 survey was complemented by a school principal survey (N = 160). In addition to the current sample, the samples of the three previous surveys with representative data for Germany are presented: 2009/10 (N = 5,005), 2013/14 (N = 5,961) and 2017/18 (N = 4,347). Discussion: The health of children and adolescents is of great public health importance. The HBSC study makes a substantial contribution by providing internationally comparable results, analysing trends, and providing stakeholders with comprehensive and representative health monitoring data.

Subjective health and psychosomatic complaints of children and adolescents in Germany: Results of the HBSC study 2009/10 - 2022.

Background: Subjective health and well-being are important health indicators in childhood and adolescence. This article shows current results and trends over time between 2009/10 and 2022. Methods: The Health Behaviour in School-aged Children (HBSC) study examined subjective health, life satisfaction and psychosomatic complaints of N = 21,788 students aged 11 to 15 years in the school years 2009/10, 2013/14, 2017/18 and in the calendar year 2022. Multivariate regression analyses show the associations between sociodemographic characteristics and well-being in 2022, as well as trends since 2009/10. Results: The majority of children and adolescents indicate a good subjective health and high life satisfaction. About half of the girls and one third of the boys report multiple psychosomatic health complaints, with a clear increase over time. Older adolescents, girls and gender diverse adolescents are at an increased risk of poor well-being. Subjective health and life satisfaction varied between 2009/10 and 2022, with a significant deterioration between 2017/18 and 2022. Conclusions: The high proportion of children and adolescents with psychosomatic complaints, as well as the observed gender and age differences, underline the need for target group-specific prevention, health promotion and continuous health monitoring.

A Southern addiction evaluation project: investigating the impact of addiction through a survey HBSC based.

Background: Adolescence is a critical phase of development characterized by numerous physical, psychological and social changes. During this stage, individuals may engage in experimentation and risky behavior, leading to increased vulnerability to addiction. This article aims to present the results of a survey based on the HBSC (Health Behavior in School-aged Children) surveillance model in a province of Southern Italy for primary and secondary school students. Methods: We conducted a prospective study from March 2020 to April 2023 through the administration of a questionnaire to students of the healthcare faculties of the University of Messina and primary and secondary school students, composed of 19 items and based on HBSC surveillance. Results: We collected a total of 664 questionnaires. We found that smoking habits increase with age: approximately 31% of secondary school students declare they are real smokers compared to 40% of HCP students. At least once, in the three study groups, students experienced alcohol consumption at different rates, with younger students having a greater propensity to drink than older students. Fortunately, in our sample, no middle school students had tried cannabis. At the same time there is a surprising decrease in gambling in all categories compared to national data. Conclusions: The presence of addictive behaviors in our sample was found to be widespread despite being in line with the national trend. Furthermore, we have observed a reduction in recent years which needs to be investigated to assess the reasons. Primary prevention is probably the main weapon in the hands of politicians and must be applied early in school and community settings to reduce prevalence.

Frequency of Vigorous physical activity and sleep difficulty in adolescents: A multiply-country cross-sectional study.

BACKGROUND: Sleep is an essential health behavior, and sleep difficulties are strongly associated with adolescent health, potentially leading to more severe sleep disorders. The beneficial effects of physical activity (PA) in alleviating sleep difficulties have been well-documented. Numerous investigations reveal influence in moderate to high-intensity physical activity (PA) positively influences sleep quality. Despite these findings, a gap in the literature exists, particularly regarding the association between frequency of vigorous-intensity physical activity (VPA) and sleep difficulties. AIM: This study aims to bridge the knowledge gap by exploring the link between sleep difficulty and frequency of VPA among adolescents. Insights are derived from analyzing data accumulated from the Health Behavior in School-aged Children (HBSC) project. METHODS: The analysis in this study utilized cross-sectional data from the HBSC (2017/2018). The study sample comprised a total of 171,233 respondents aged 11, 13, and 15 years, with males representing 51.1% of sample. Measurement instruments included a self-administered questionnaire, providing direct insight into sleep difficulty and frequency of VPA levels. Statistical analysis on the associaiton between frequency of VPA and sleep difficulties was conducted using Generalized Linear Models. RESULTS: 50.0% of adolescents reported no sleep difficulties, while 12.3% experienced sleep issues daily. Additionally, 17.1% of adolescents engaged in frequency of VPA on a daily basis, while 6.4% never participated in such activities. daily VPA was associated with fewer sleep difficulties (OR = 1.07 [1.00, 1.15]), 4-6 times a week (OR = 1.08 [1.01, 1.15]), and 2-3 times a week (OR = 1.08 [1.02, 1.16]). However, no significant association was found between sleep difficulties and frequency of VPA in girls. Furthermore, a negative association was observed between sleep difficulties and all frequencies of VPA (p < 0.05) in 11-year-old adolescents. For 13-year-olds, daily VPA was significantly associated with fewer sleep difficulties (OR = 1.10 [1.02, 1.19]), 4-6 times a week (OR = 1.15 [1.07, 1.24]), 2-3 times a week (OR = 1.19 [1.10, 1.27]), and once a week (OR = 1.13 [1.05, 1.22]). However, no significant association was found between sleep difficulties and frequency of VPA in 15-year-old adolescents. CONCLUSION: More participations in VPA would be an effective approach to reduce sleep difficulties in adolescents. Insights gleaned from this research illustrate a discernible link between sleep difficulty and frequency of VPA, particularly notable in male and 13-year-old participants. It is also imperative to underscore the variability in the connection between sleep difficulty and frequency of VPA, distinctly influenced by factors such as gender and age. Consequently, tailoring sleep intervention methodologies to align with the specific needs dictated by these variables emerges as a pivotal recommendation.

The international Family Affluence Scale (FAS): Charting 25 years of indicator development, evidence produced, and policy impact on adolescent health inequalities.

In the absence of suitable indicators of adolescent socioeconomic status, the Family Affluence Scale (FAS) was first developed in Scotland 25 years ago. Since then, it has been adapted for use in the Health Behaviour in School-Aged Children (HBSC) Study to research inequalities in adolescent health in Europe and North America. FAS has also been used as an indicator of adolescent socioeconomic status in research studies outside of HBSC, worldwide. There has been a need for FAS to evolve and change its component items over time in order to take into account social and technological changes influencing the families of adolescents. This paper uniquely charts the development of FAS describing the methodological work carried out to validate the measure internationally and over time. It also presents an overview of the body of evidence on adolescent health inequalities produced over years from the HBSC Study and other research studies. Interviews conducted with policy stakeholders reveal that the evidence from FAS-related HBSC work has influenced their strategic work to raise awareness of inequalities and make the case for action to address these. Finally, the future of FAS is discussed with respect to its continual evolution in the context of technological, environmental and social change.

Traditional bullying, cyberbullying, and quality of life among adolescents in 35 countries: Do cultural values matter?

RATIONALE: Substantial evidence indicates that involvement in school bullying has been linked to lower quality of life (QoL). Yet there is little information elucidating the link between bullying involvement and QoL in different cultures. OBJECTIVE: This study investigated the associations between different types of bullying involvement and QoL among adolescents. The moderating roles of cultural values in the relationship between bullying involvement and QoL were examined. METHODS: This study included representative samples from 35 countries (N = 184,017) using data from the 2017/2018 Health Behavior in School-Aged Children (HBSC) survey and the new 2023 World Cultural Map Scores from the World Values Survey Wave 7 (2017/2021). Multilevel mixed-effects analysis was employed to examine individual-level and country-level effects simultaneously. RESULTS: All types of bullying involvement were associated with lower QoL, with being a victim having the lowest QoL. Adolescents in societies that prioritize higher self-expression values exhibited a reduced propensity to engage in school bullying. In countries with higher self-expression values, there was a more pronounced negative association between bullying involvement and QoL. Traditional/Secular-rational values had no significant and consistent moderating effect on the association between bullying involvement and QoL. Those results were quite similar for both traditional bullying and cyberbullying. CONCLUSION: These findings imply that cultural values are closely intertwined with adolescent bullying and quality of life. Therefore, prevention and intervention programs should pay more attention to addressing bullying and promoting the QoL of adolescents according to various cultural values.

Income inequality and socioeconomic differences in bullying perpetration among adolescents in post-communist countries of Europe: Findings from the HBSC study.

Background: Adolescent bullying is a major public health concern in post-Communist countries of Europe (PCCE). We studied the impact of income inequality on the prevalence of and socioeconomic differences in bullying perpetration. Methods: Nationally representative samples of adolescents aged 11-15 years from 14 PCCE participating in the Health Behavior in School-aged Children survey during 2017-18 years were included. Multilevel logistic regression models were fitted. Results: Overall, 71,119 adolescents participated in the survey. About 27.7 % of country differences in bullying perpetration were attributable to high income inequality. Adolescents with low and high family socioeconomic status (SES) had a 10-15 % greater risk (P < 0.05) of bullying perpetration compared to middle-SES adolescents. In cross-level interaction, the risk of bullying perpetration was the highest among high-SES adolescents from countries with wider income inequality (P-interaction = 0.003). The odds ratios of bullying perpetration comparing high- vs. low-SES adolescents ranged from 0.67 in the least unequal to 1.59 in the most unequal countries. Conclusions: Our findings suggest that high income inequality might contribute to school bullying among adolescents in PCCE, particularly those from high-SES families. The necessary political and economic interventions should focus on improving the country socioeconomic environment in PCCE. Moving towards less neoliberal policies and creating a strong welfare state that promotes the population's economic and social well-being and reduces income inequality might be a necessary component of macro-level strategies aimed at preventing bullying among adolescents. Targeted public health interventions might be required for high-SES adolescents in countries with wide income inequality.

Adolescent Toothbrushing and Its Association with Sociodemographic Factors-Time Trends from 1994 to 2018 in Twenty Countries.

Regular toothbrushing is the primary self-care method to prevent the most common dental diseases and is considered an important public health indicator. This retrospective observational study aimed to examine cross-national time trends in adolescent toothbrushing behaviour and its association with sociodemographic factors between 1994 and 2018. We studied data from 20 countries that conducted seven surveys of the Health Behaviour in School-aged Children (HBSC) study. Adolescents aged 11, 13 and 15 years responded to questions on their toothbrushing frequency, family affluence and structure. Altogether, reports of 691,559 students were analysed using descriptive statistics and binominal logistic regression. The findings showed an overall positive trend in the prevalence of more-than-once-a-day toothbrushing frequency during the entire study period mainly due to a noticeable increase from 1994 to 2010 (except Denmark and Sweden); this trend continued significantly thereafter in 12 of 20 countries. Across all countries, girls and adolescents from more affluent families were more likely to brush their teeth regularly. These relationships remained unchanged throughout the study period, whereas the age-related difference in toothbrushing prevalence decreased noticeably, and the negative relationship between toothbrushing and living in a non-intact family became evident. While the prevalence of regular toothbrushing among adolescents has increased in recent decades, it is still far behind the recommended level of twice-daily brushing for everyone across all countries. The promotion of toothbrushing needs to start at an early age, with a special focus on boys and adolescents from low-affluence and non-intact families.