Physical activity behaviours in adolescence: current evidence and opportunities for intervention.

Young people aged 10-24 years constitute 24% of the world's population; investing in their health could yield a triple benefit-eg, today, into adulthood, and for the next generation. However, in physical activity research, this life stage is poorly understood, with the evidence dominated by research in younger adolescents (aged 10-14 years), school settings, and high-income countries. Globally, 80% of adolescents are insufficiently active, and many adolescents engage in 2 h or more daily recreational screen time. In this Series paper, we present the most up-to-date global evidence on adolescent physical activity and discuss directions for identifying potential solutions to enhance physical activity in the adolescent population. Adolescent physical inactivity probably contributes to key global health problems, including cardiometabolic and mental health disorders, but the evidence is methodologically weak. Evidence-based solutions focus on three key components of the adolescent physical activity system: supportive schools, the social and digital environment, and multipurpose urban environments. Despite an increasing volume of research focused on adolescents, there are still important knowledge gaps, and efforts to improve adolescent physical activity surveillance, research, intervention implementation, and policy development are urgently needed.

Adolescent Health Series: The health of adolescents in sub-Saharan Africa: Challenges and opportunities.

OBJECTIVE: This article provides a concise overview of the current challenges that adolescents face in sub-Saharan Africa, summarises possible solutions and ongoing efforts to implement these, and briefly introduces the subsequent papers of this series. METHODS: We draw on data from the WHO Maternal, Newborn, Child and Adolescent Health and Ageing Data Portal. RESULTS: The opportunity provided by the growing number of adolescents in sub-Saharan Africa will only be realised if they survive, are healthy, receive a quality education and remain in Africa rather than joining the increasing out-migration exodus. Fortunately, there is an increasing focus on adolescent health and well-being both globally and in sub-Saharan Africa, and growing knowledge of what to do to promote adolescent health and well-being and how to do it, and a powerful resource in the form of adolescents themselves. CONCLUSION: There is no time to lose. African adolescents demand it, but are also ready to be part of the solution.

Levels of domain-specific physical activity at work, in the household, for travel and for leisure among 327 789 adults from 104 countries.

OBJECTIVE: To compare the country-level absolute and relative contributions of physical activity at work and in the household, for travel, and during leisure-time to total moderate-to-vigorous physical activity (MVPA). METHODS: We used data collected between 2002 and 2019 from 327 789 participants across 104 countries and territories (n=24 low, n=34 lower-middle, n=30 upper-middle, n=16 high-income) from all six World Health Organization (WHO) regions. We calculated mean min/week of work/household, travel and leisure MVPA and compared their relative contributions to total MVPA using Global Physical Activity Questionnaire data. We compared patterns by country, sex and age group (25-44 and 45-64 years). RESULTS: Mean MVPA in work/household, travel and leisure domains across the 104 countries was 950 (IQR 618-1198), 327 (190-405) and 104 (51-131) min/week, respectively. Corresponding relative contributions to total MVPA were 52% (IQR 44%-63%), 36% (25%-45%) and 12% (4%-15%), respectively. Work/household was the highest contributor in 80 countries; travel in 23; leisure in just one. In both absolute and relative terms, low-income countries tended to show higher work/household (1233 min/week, 57%) and lower leisure MVPA levels (72 min/week, 4%). Travel MVPA duration was higher in low-income countries but there was no obvious pattern in the relative contributions. Women tended to have relatively less work/household and more travel MVPA; age groups were generally similar. CONCLUSION: In the largest domain-specific physical activity study to date, we found considerable country-level variation in how MVPA is accumulated. Such information is essential to inform national and global policy and future investments to provide opportunities to be active, accounting for country context.

Progress in physical activity over the Olympic quadrennium.

On the eve of the 2012 summer Olympic Games, the first Lancet Series on physical activity established that physical inactivity was a global pandemic, and global public health action was urgently needed. The present paper summarises progress on the topics covered in the first Series. In the past 4 years, more countries have been monitoring the prevalence of physical inactivity, although evidence of any improvements in prevalence is still scarce. According to emerging evidence on brain health, physical inactivity accounts for about 3·8% of cases of dementia worldwide. An increase in research on the correlates of physical activity in low-income and middle-income countries (LMICs) is providing a better evidence base for development of context-relevant interventions. A finding specific to LMICs was that physical inactivity was higher in urban (vs rural) residents, which is a cause for concern because of the global trends toward urbanisation. A small but increasing number of intervention studies from LMICs provide initial evidence that community-based interventions can be effective. Although about 80% of countries reported having national physical activity policies or plans, such policies were operational in only about 56% of countries. There are important barriers to policy implementation that must be overcome before progress in increasing physical activity can be expected. Despite signs of progress, efforts to improve physical activity surveillance, research, capacity for intervention, and policy implementation are needed, especially among LMICs.

The World Health Organization STEPwise Approach to Noncommunicable Disease Risk-Factor Surveillance: Methods, Challenges, and Opportunities.

OBJECTIVES: We sought to outline the framework and methods used by the World Health Organization (WHO) STEPwise approach to noncommunicable disease (NCD) surveillance (STEPS), describe the development and current status, and discuss strengths, limitations, and future directions of STEPS surveillance. METHODS: STEPS is a WHO-developed, standardized but flexible framework for countries to monitor the main NCD risk factors through questionnaire assessment and physical and biochemical measurements. It is coordinated by national authorities of the implementing country. The STEPS surveys are generally household-based and interviewer-administered, with scientifically selected samples of around 5000 participants. RESULTS: To date, 122 countries across all 6 WHO regions have completed data collection for STEPS or STEPS-aligned surveys. CONCLUSIONS: STEPS data are being used to inform NCD policies and track risk-factor trends. Future priorities include strengthening these linkages from data to action on NCDs at the country level, and continuing to develop STEPS' capacities to enable a regular and continuous cycle of risk-factor surveillance worldwide.

Relevance of the Sustainable Development Goals (SDGs) to Adolescent Health Measurement: A Systematic Mapping of the SDG Framework and Global Adolescent Health Indicators.

PURPOSE: To assess the relevance of the Sustainable Development Goals (SDGs) framework for adolescent health measurement, both in terms of age disaggregation and different health domains captured, and how the adolescent health indicators recommended by the Global Action for Measurement of Adolescent Health (GAMA) can complement the SDG framework. METHODS: We conducted a desk review to systematically map all 248 SDG indicators using the UN metadata repository in three steps: 1) age-related mandates for SDG reporting; 2) linkages between the SDG indicators and priority areas for adolescent health measurement; 3) comparison between the GAMA indicators and the SDG framework. RESULTS: Of the 248 SDG indicators, 35 (14%) targeted an age range overlapping with adolescence (10-19 years) and 33 (13%) called for age disaggregation. Only one indicator (3.7.2 "adolescent birth rate") covered the entire 10-19 age range. Almost half (41%) of the SDG indicators were directly related to adolescent health, but only 33 of those (13% of all SDG indicators) overlapped with the ages 10-19, and 15 (6% of all SDG indicators) explicitly mandated age disaggregation. Among the 47 GAMA indicators, five corresponded to existing SDG indicators, and eight were adolescent-specific age adaptations. Several GAMA indicators shed light on aspects not tracked in the SDG framework, such as obesity, mental health, physical activity, and bullying among 10-19-year-olds. DISCUSSION: Adolescent health cannot be monitored comprehensively with the SDG framework alone. The GAMA indicators complement this framework via age-disaggregated adaptations and by tracking aspects of adolescent health currently absent from the SDGs.

National, regional, and global trends in insufficient physical activity among adults from 2000 to 2022: a pooled analysis of 507 population-based surveys with 5·7 million participants.

BACKGROUND: Insufficient physical activity increases the risk of non-communicable diseases, poor physical and cognitive function, weight gain, and mental ill-health. Global prevalence of adult insufficient physical activity was last published for 2016, with limited trend data. We aimed to estimate the prevalence of insufficient physical activity for 197 countries and territories, from 2000 to 2022. METHODS: We collated physical activity reported by adults (aged ≥18 years) in population-based surveys. Insufficient physical activity was defined as not doing 150 minutes of moderate-intensity activity, 75 minutes of vigorous-intensity activity, or an equivalent combination per week. We used a Bayesian hierarchical model to compute estimates of insufficient physical activity by country or territory, year, age, and sex. We assessed whether countries or territories, regions, and the world would meet the global target of a 15% relative reduction of the prevalence of insufficient physical activity by 2030 if 2010-22 trends continue. FINDINGS: We included 507 surveys across 163 countries and territories. The global age-standardised prevalence of insufficient physical activity was 31·3% (95% uncertainty interval 28·6-34·0) in 2022, an increase from 23·4% (21·1-26·0) in 2000 and 26·4% (24·8-27·9) in 2010. Prevalence was increasing in 103 (52%) of 197 countries and territories and six (67%) of nine regions, and was declining in the remainder. Prevalence was 5 percentage points higher among female (33·8% [29·9-37·7]) than male (28·7% [25·0-32·6]) individuals. Insufficient physical activity increased in people aged 60 years and older in all regions and both sexes, but age patterns differed for those younger than 60 years. If 2010-22 trends continue, the global target of a 15% relative reduction between 2010 and 2030 will not be met (posterior probability <0·01); however, two regions, Oceania and sub-Saharan Africa, were on track with considerable uncertainty (posterior probabilities 0·70-0·74). INTERPRETATION: Concerted multi-sectoral efforts to reduce insufficient physical activity levels are needed to meet the 2030 target. Physical activity promotion should not exacerbate sex, age, or geographical inequalities. FUNDING: Ministry of Public Health, Qatar, and World Health Organization. TRANSLATIONS: For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.

Towards Harmonized Adolescent Health Measurement: Assessing Alignment Between Current Recommendations and the Global Action for Measurement of Adolescent Health-Recommended Indicators.

PURPOSE: This study identified alignment of indicators across different initiatives and data collection instruments as a foundation for future harmonization of adolescent health measurement. METHODS: Using the Global Action for Measurement of Adolescent health (GAMA) recommended indicators as the basis for comparison, we conducted a desk review of 14 global-level initiatives, such as the Sustainable Development Goals and the Global Strategy for Women's, Children's and Adolescents' Health, and five multicountry survey programs, such as the Multiple Indicator Cluster Surveys and the Global school-based Student Health Survey. We identified initiative and survey indicators similar to a GAMA indicator, deconstructed indicators into standard elements to facilitate comparison, and assessed alignment to the corresponding GAMA indicator across each of the elements. RESULTS: A total of 144 initiative indicators and 90 survey indicators were identified. Twenty-four initiative indicators (17%) and 14 survey indicators (16%) matched the corresponding GAMA indicators across all elements. Population of interest was the most commonly discrepant element; whereas GAMA indicators mostly refer to ages 10-19, many survey and initiative indicators encompass only part of this age range, for example, 15-19-year-olds as a subset of adults ages 15-49 years. An additional 53 initiative indicators (39%) and 44 survey indicators (49%) matched on all elements except the population of interest. DISCUSSION: The current adolescent measurement landscape is inconsistent, with differing recommendations on what and how to measure. Findings from this study support efforts to promote indicator alignment and harmonization across adolescent health measurement stakeholders at the global, regional, and country levels.

Indicators to Measure Adolescent Health at the Country, Regional, and Global Levels: Results of a Five-Year Selection Process by the Global Action for the Measurement of Adolescent Health.

PURPOSE: To improve adolescent health measurement, the Global Action for the Measurement of Adolescent health (GAMA) Advisory Group was formed in 2018 and published a draft list of 52 indicators across six adolescent health domains in 2022. We describe the process and results of selecting the adolescent health indicators recommended by GAMA (hereafter, "GAMA-recommended indicators"). METHODS: Each indicator in the draft list was assessed using the following inputs: (1) availability of data and stakeholders' perceptions on their relevance, acceptability, and feasibility across selected countries; (2) alignment with current measurement recommendations and practices; and (3) data in global databases. Topic-specific working groups comprised of GAMA experts and representatives of United Nations partner agencies reviewed results and provided preliminary recommendations, which were appraised by all GAMA members and finalized. RESULTS: There are 47 GAMA-recommended indicators (36 core and 11 additional) for adolescent health measurement across six domains: policies, programs, and laws (4 indicators); systems performance and interventions (4); health determinants (7); health behaviors and risks (20); subjective well-being (2); and health outcomes and conditions (10). DISCUSSION: These indicators are the result of a robust and structured five-year process to identify a priority set of indicators with relevance to adolescent health globally. This inclusive and participatory approach incorporated inputs from a broad range of stakeholders, including adolescents and young people themselves. The GAMA-recommended indicators are now ready to be used to measure adolescent health at the country, regional, and global levels.

Exploring a Preliminary Set of Indicators to Measure Adolescent Health: Results From a 12-Country Feasibility Study.

PURPOSE: To explore data availability, perceived relevance, acceptability and feasibility of implementing 52 draft indicators for adolescent health measurement in different countries globally. METHODS: A mixed-methods, sequential explanatory study was conducted in 12 countries. An online spreadsheet was used to assess data availability and a stakeholder survey to assess perceived relevance, acceptability, and feasibility of implementing each draft indicator proposed by the Global Action for Measurement of Adolescent health (GAMA). The assessments were discussed in virtual meetings with all countries and in deep dives with three countries. Findings were synthesized using descriptive statistics and qualitative thematic analysis. RESULTS: Data availability varied across the 52 draft GAMA indicators and across countries. Nine countries reported measuring over half of the indicators. Most indicators were rated relevant by stakeholders, while some were considered less acceptable and feasible. The ten lowest-ranking indicators were related to mental health, sexual health and substance use; the highest-ranking indicators centered on broader adolescent health issues, like use of health services. Indicators with higher data availability and alignment with national priorities were generally considered most relevant, acceptable and feasible. Barriers to measurement included legal, ethical and sensitivity issues, challenges with multi-sectoral coordination and data systems flexibility. DISCUSSION: Most of the draft GAMA indicators were deemed relevant and feasible, but contextual priorities and perceived acceptability influenced their implementation in countries. To increase their use for a more comprehensive understanding of adolescent health, better multi-sectoral coordination and tailored capacity building to accommodate the diverse data systems in countries will be required.

Global physical activity levels: surveillance progress, pitfalls, and prospects.

To implement effective non-communicable disease prevention programmes, policy makers need data for physical activity levels and trends. In this report, we describe physical activity levels worldwide with data for adults (15 years or older) from 122 countries and for adolescents (13-15-years-old) from 105 countries. Worldwide, 31·1% (95% CI 30·9-31·2) of adults are physically inactive, with proportions ranging from 17·0% (16·8-17·2) in southeast Asia to about 43% in the Americas and the eastern Mediterranean. Inactivity rises with age, is higher in women than in men, and is increased in high-income countries. The proportion of 13-15-year-olds doing fewer than 60 min of physical activity of moderate to vigorous intensity per day is 80·3% (80·1-80·5); boys are more active than are girls. Continued improvement in monitoring of physical activity would help to guide development of policies and programmes to increase activity levels and to reduce the burden of non-communicable diseases.

Effectiveness of a participatory approach to develop school health interventions in four low resource cities: study protocol of the 'empowering adolescents to lead change using health data' cluster randomised controlled trial.

INTRODUCTION: Comprehensive local data on adolescent health are often lacking, particularly in lower resource settings. Furthermore, there are knowledge gaps around which interventions are effective to support healthy behaviours. This study generates health information for students from cities in four middle-income countries to plan, implement and subsequently evaluate a package of interventions to improve health outcomes. METHODS AND ANALYSIS: We will conduct a cluster randomised controlled trial in schools in Fez, Morocco; Jaipur, India; Saint Catherine Parish, Jamaica; and Sekondi-Takoradi, Ghana. In each city, approximately 30 schools will be randomly selected and assigned to the control or intervention arm. Baseline data collection includes three components. First, a Global School Health Policies and Practices Survey (G-SHPPS) to be completed by principals of all selected schools. Second, a Global School-based Student Health Survey (GSHS) to be administered to a target sample of n=3153 13-17 years old students of randomly selected classes of these schools, including questions on alcohol, tobacco and drug use, diet, hygiene, mental health, physical activity, protective factors, sexual behaviours, violence and injury. Third, a study validating the GSHS physical activity questions against wrist-worn accelerometry in one randomly selected class in each control school (n approximately 300 students per city). Intervention schools will develop a suite of interventions using a participatory approach driven by students and involving parents/guardians, teachers and community stakeholders. Interventions will aim to change existing structures and policies at schools to positively influence students' behaviour, using the collected data and guided by the framework for Making Every School a Health Promoting School. Outcomes will be assessed for differential change after a 2-year follow-up. ETHICS AND DISSEMINATION: The study was approved by WHO's Research Ethics Review Committee; by the Jodhpur School of Public Health's Institutional Review Board for Jaipur, India; by the Noguchi Memorial Institute for Medical Research Institutional Review Board for Sekondi-Takoradi, Ghana; by the Ministry of Health and Wellness' Advisory Panel on Ethics and Medico-Legal Affairs for St Catherine Parish, Jamaica, and by the Comité d'éthique pour la recherche biomédicale of the Université Mohammed V of Rabat for Fez, Morocco. Findings will be shared through open access publications and conferences. TRIAL REGISTRATION NUMBER: NCT04963426.

Socioeconomic inequalities in risk factors for non communicable diseases in low-income and middle-income countries: results from the World Health Survey.

BACKGROUND: Monitoring inequalities in non communicable disease risk factor prevalence can help to inform and target effective interventions. The prevalence of current daily smoking, low fruit and vegetable consumption, physical inactivity, and heavy episodic alcohol drinking were quantified and compared across wealth and education levels in low- and middle-income country groups. METHODS: This study included self-reported data from 232,056 adult participants in 48 countries, derived from the 2002-2004 World Health Survey. Data were stratified by sex and low- or middle-income country status. The main outcome measurements were risk factor prevalence rates reported by wealth quintile and five levels of educational attainment. Socioeconomic inequalities were measured using the slope index of inequality, reflecting differences in prevalence rates, and the relative index of inequality, reflecting the prevalence ratio between the two extremes of wealth or education accounting for the entire distribution. Data were adjusted for confounding factors: sex, age, marital status, area of residence, and country of residence. RESULTS: Smoking and low fruit and vegetable consumption were significantly higher among lower socioeconomic groups. The highest wealth-related absolute inequality was seen in smoking among men of low- income country group (slope index of inequality 23.0 percentage points; 95% confidence interval 19.6, 26.4). The slope index of inequality for low fruit and vegetable consumption across the entire distribution of education was around 8 percentage points in both sexes and both country income groups. Physical inactivity was less prevalent in populations of low socioeconomic status, especially in low-income countries (relative index of inequality: (men) 0.46, 95% confidence interval 0.33, 0.64; (women) 0.52, 95% confidence interval 0.42, 0.65). Mixed patterns were found for heavy drinking. CONCLUSIONS: Disaggregated analysis of the prevalence of non-communicable disease risk factors demonstrated different patterns and varying degrees of socioeconomic inequalities across low- and middle-income settings. Interventions should aim to reach and achieve sustained benefits for high-risk populations.

Priority Indicators for Adolescent Health Measurement - Recommendations From the Global Action for Measurement of Adolescent Health (GAMA) Advisory Group.

PURPOSE: This article describes the selection of priority indicators for adolescent (10-19 years) health measurement proposed by the Global Action for Measurement of Adolescent health advisory group and partners, building on previous work identifying 33 core measurement areas and mapping 413 indicators across these areas. METHODS: The indicator selection process considered inputs from a broad range of stakeholders through a structured four-step approach: (1) definition of selection criteria and indicator scoring; (2) development of a draft list of indicators with metadata; (3) collection of public feedback through a survey; and (4) review of the feedback and finalization of the indicator list. As a part of the process, measurement gaps were also identified. RESULTS: Fifty-two priority indicators were identified, including 36 core indicators considered to be most important for measuring the health of all adolescents, one alternative indicator for settings where measuring the core indicator is not feasible, and 15 additional indicators for settings where further detail on a topic would add value. Of these indicators, 17 (33%) measure health behaviors and risks, 16 (31%) health outcomes and conditions, eight (15%) health determinants, five (10%) systems performance and interventions, four (8%) policies, programmes, laws, and two (4%) subjective well-being. DISCUSSION: A consensus list of priority indicators with metadata covering the most important health issues for adolescents was developed with structured inputs from a broad range of stakeholders. This list will now be pilot tested to assess the feasibility of indicator data collection to inform global, regional, national, and sub-national monitoring.

Global and regional levels and trends of child and adolescent morbidity from 2000 to 2016: an analysis of years lost due to disability (YLDs).

INTRODUCTION: Non-fatal health loss makes a substantial contribution to the total disease burden among children and adolescents. An analysis of these morbidity patterns is essential to plan interventions that improve the health and well-being of children and adolescents. Our objective was to describe current levels and trends in the non-fatal disease burden from 2000 to 2016 among children and adolescents aged 0-19 years. METHODS: We used years lost due to disability (YLD) estimates in WHO's Global Health Estimates to describe the non-fatal disease burden from 2000 to 2016 for the age groups 0-27 days, 28 days-11 months, 1-4 years, 5-9 years, 10-14 years and 15-19 years globally and by modified WHO region. To describe causes of YLDs, we used 18 broad cause groups and 54 specific cause categories. RESULTS: In 2016, the total number of YLDs globally among those aged 0-19 years was about 130 million, or 51 per 1000 population, ranging from 30 among neonates aged 0-27 days to 67 among older adolescents aged 15-19 years. Global progress since 2000 in reducing the non-fatal disease burden has been limited (53 per 1000 in 2000 for children and adolescents aged 0-19 years). The most important causes of YLDs included iron-deficiency anaemia and skin diseases for both sexes, across age groups and regions. For young children under 5 years of age, congenital anomalies, protein-energy malnutrition and diarrhoeal diseases were important causes of YLDs, while childhood behavioural disorders, asthma, anxiety disorders and depressive disorders were important causes for older children and adolescents. We found important variations between sexes and between regions, particularly among adolescents, that need to be addressed context-specifically. CONCLUSION: The disappointingly slow progress in reducing the global non-fatal disease burden among children and adolescents contrasts starkly with the major reductions in mortality over the first 17 years of this century. More effective action is needed to reduce the non-fatal disease burden among children and adolescents, with interventions tailored for each age group, sex and world region.

Patterns and trends in causes of child and adolescent mortality 2000-2016: setting the scene for child health redesign.

The under-5 mortality rate has declined from 93 deaths per 1000 live births in 1990 to 39 per 1000 live births in 2018. This improvement in child survival warrants an examination of age-specific trends and causes of death over time and across regions and an extension of the survival focus to older children and adolescents. We examine patterns and trends in mortality for neonates, postneonatal infants, young children, older children, young adolescents and older adolescents from 2000 to 2016. Levels and trends in causes of death for children and adolescents under 20 years of age are based on United Nations Inter-agency Group for Child Mortality Estimation for all-cause mortality, the Maternal and Child Epidemiology Estimation group for cause of death among children under-5 and WHO Global Health Estimates for 5-19 year-olds. From 2000 to 2016, the proportion of deaths in young children aged 1-4 years declined in most regions while neonatal deaths became over 25% of all deaths under 20 years in all regions and over 50% of all under-5 deaths in all regions except for sub-Saharan Africa which remains the region with the highest under-5 mortality in the world. Although these estimates have great variability at the country level, the overall regional patterns show that mortality in children under the age of 5 is increasingly concentrated in the neonatal period and in some regions, in older adolescents. The leading causes of disease for children under-5 remain preterm birth and infectious diseases, pneumonia, diarrhoea and malaria. For older children and adolescents, injuries become important causes of death as do interpersonal violence and self-harm. Causes of death vary by region.

A Scoping Review of Adolescent Health Indicators.

PURPOSE: A host of recent initiatives relating to adolescent health have been accompanied by varying indicator recommendations, with little stakeholder coordination. We assessed currently included adolescent health-related indicators for their measurement focus, identified overlap across initiatives, and determined measurement gaps. METHODS: We conducted a scoping review to map the existing indicator landscape as depicted by major measurement initiatives. We classified indicators as per 33 previously identified core adolescent health measurement areas across five domains and by age groups. We also identified indicators common across measurement initiatives even if differing in details. RESULTS: We identified 413 indicators across 16 measurement initiatives, with most measuring health outcomes and conditions (162 [39%]) and health behaviors and risks (136 [33%]); followed by policies, programs, and laws (49 [12%]); health determinants (44 [11%]); and system performance and interventions (22 [5%]). Age specification was available for 221 (54%) indicators, with 51 (23%) focusing on the full adolescent age range (10-19 years), 1 (<1%) on 10-14 years, 27 (12%) on 15-19 years, and 142 (64%) on a broader age range including adolescents. No definitional information, such as numerator and denominator, was available for 138 indicators. We identified 236 distinct indicators after accounting for overlap. CONCLUSION: The adolescent health measurement landscape is vast and includes substantial variation among indicators purportedly assessing the same concept. Gaps persist in measuring systems performance and interventions; policies, programs, and laws; and younger adolescents' health. Addressing these gaps and harmonizing measurement is fundamental to improve program implementation and accountability for adolescent health globally.

Priority Areas for Adolescent Health Measurement.

PURPOSE: We establish priority areas for adolescent health measurement and identify current gaps, aiming to focus resources on the most relevant data to improve adolescent health. METHODS: We collected four critical inputs to inform priority setting: perspectives of youth representatives, country priorities, disease burden, and existing measurement efforts. Health areas identified from the inputs were grouped, mapped, and summarized according to their frequency in the inputs. Using a Delphi-like approach, international experts then selected core, expanded, and context-specific priority areas for adolescent health measurement from all health areas identified. RESULTS: Across the four inputs, we identified 99 measurement areas relevant to adolescent health and grouped them under six domains: policies, programs, laws; systems performance and interventions; health determinants; health behaviors and risks; subjective well-being; and health outcomes and conditions. Areas most frequently occurring were mental health and weight status in youth representatives' opinions; sexual and reproductive health and HIV/AIDS in country policies and perspectives; road injury, self-harm, skin diseases, and mental disorders in the disease burden analysis; and adolescent fertility in measurement initiatives. Considering all four inputs, experts selected 33 core, 19 expanded, and 6 context-specific adolescent health measurement areas. CONCLUSION: The adolescent health measurement landscape is vast, covering a large variety of topics. The foci of the measurement initiatives we reviewed do not reflect the most important health areas according to youth representatives' or country-level perspectives, or the adolescent disease burden. Based on these inputs, we propose a set of priority areas to focus national and global adolescent health measurement.

A call for standardised age-disaggregated health data.

The 2030 Sustainable Development Goals agenda calls for health data to be disaggregated by age. However, age groupings used to record and report health data vary greatly, hindering the harmonisation, comparability, and usefulness of these data, within and across countries. This variability has become especially evident during the COVID-19 pandemic, when there was an urgent need for rapid cross-country analyses of epidemiological patterns by age to direct public health action, but such analyses were limited by the lack of standard age categories. In this Personal View, we propose a recommended set of age groupings to address this issue. These groupings are informed by age-specific patterns of morbidity, mortality, and health risks, and by opportunities for prevention and disease intervention. We recommend age groupings of 5 years for all health data, except for those younger than 5 years, during which time there are rapid biological and physiological changes that justify a finer disaggregation. Although the focus of this Personal View is on the standardisation of the analysis and display of age groups, we also outline the challenges faced in collecting data on exact age, especially for health facilities and surveillance data. The proposed age disaggregation should facilitate targeted, age-specific policies and actions for health care and disease management.

Physical activity and sedentary behavior among schoolchildren: a 34-country comparison.

OBJECTIVE: To describe and compare levels of physical activity and sedentary behavior in schoolchildren from 34 countries across 5 WHO Regions. STUDY DESIGN: The analysis included 72,845 schoolchildren from 34 countries that participated in the Global School-based Student Health Survey (GSHS) and conducted data collection between 2003 and 2007. The questionnaire included questions on overall physical activity, walking, or biking to school, and on time spent sitting. RESULTS: Very few students engaged in sufficient physical activity. Across all countries, 23.8% of boys and 15.4% of girls met recommendations, with the lowest prevalence in Philippines and Zambia (both 8.8%) and the highest in India (37.5%). The prevalence of walking or riding a bicycle to school ranged from 18.6% in United Arab Emirates to 84.8% in China. In more than half of the countries, more than one third of the students spent 3 or more hours per day on sedentary activities, excluding the hours spent sitting at school and doing homework. CONCLUSIONS: The great majority of students did not meet physical activity recommendations. Additionally, levels of sedentariness were high. These findings require immediate action, and efforts should be made worldwide to increase levels of physical activity among schoolchildren.