Testing validity of FitnessGram in two samples of US adolescents (12-15 years)

Background

This study examined the validity of the FitnessGram® criterion-reference cut-points for cardiorespiratory fitness (CRF) based on two samples of US adolescents (aged 12–15 years). This study also established the CRF cut-points for metabolically healthy weight status based on a recent national fitness survey for the purposes of cross-validating with pre-existing cut-points including FitnessGram.

Methods

Two cross-sectional data from the 2003–2004 National Health and Nutrition Examination Survey (NHANES) (n = 378) and 2012 NHANES National Youth Fitness Survey (NNYFS) (n = 451) were used. CRF (estimated V˙O_2max in mL/kg/min) was estimated from a submaximal exercise test. CRF categories based on FitnessGram cut-points, a clustered cardiometabolic risk factors score and weight status were used. A series of Receiver Operating Characteristic (ROC) curve analyses were conducted to identify age- and sex-specific CRF cut-points that were optimal for metabolically healthy weight status.

Results

Based on FitnessGram cut-points, having high risk CRF, but not low risk CRF, was associated with high cardiometabolic risk (OR = 3.17, 95% CI = 1.14–8.79) and unhealthy weight status (OR = 5.81, 95% CI = 3.49–9.68). The optimal CRF cut-points for 12-13-year-olds and 14-15-year-olds were 40 and 43 mL/kg/min in males and 39 and 34 mL/kg/min in females, respectively. Compared to meeting new CRF cut-points, not meeting new CRF cut-points was associated with higher odds of showing high cardiometabolic risk (OR = 2.91, 95% CI = 1.47–5.77) and metabolically unhealthy weight status (OR = 4.47, 95% CI = 2.83–7.05).

Conclusion

FitnessGram CRF cut-point itself has rarely been scrutinized in previous literature. Our findings provide partial support for FitnessGram based on two samples of US adolescents. CRF cut-points established in this study supports international criterion-referenced cut-points as well as FitnessGram cut-points only for males. FitnessGram should be continuously monitored and scrutinized using different samples.

Evaluation of the process and outcomes of the Global Matrix 3.0 of physical activity grades for children and youth

BACKGROUND/OBJECTIVE

Participation in the Active Healthy Kids Global Alliance (AHKGA) Global Matrix initiative represents a significant work and resource investment for Report Card teams. The objective of this paper was to evaluate the process and findings of the Global Matrix 3.0 and formulate recommendations for improvement.

METHODS

The evaluation of the Global Matrix 3.0 was planned prior to its development and a list of potential process, impact, and outcome indicators were pre-identified. These indicators were informed by online surveys, direct reports, MailChimp's statistics, Google Analytics of the AHKGA website, and emails sent to the AHKGA Board of Directors.

RESULTS

Five online surveys were completed by 88%-100% of the targeted respondents. High satisfaction ratings were observed for most of the Global Matrix 3.0 methods, key steps, concepts, and the resources (e-blasts and website) provided by the AHKGA. A total of 496 open-ended comments were provided in the five surveys, including 199 comments reporting issue(s), and 38 reporting both positive feedback and issue(s). The participating Report Card teams successfully assigned a grade to each physical activity indicator, produced a Report Card document, and wrote a short Report Card article.

CONCLUSION

This evaluation process allowed for the identification of needed improvements and the formulation of recommendations for future Global Matrix initiatives. This work highlighted the need for the development of physical activity behavior assessment tools that would be internationally adopted and culturally adaptable to varying contexts to improve the standardization of physical activity surveillance at the global scale.

Breastfeeding and childhood obesity: A 12-country study

This study aimed to examine the association between breastfeeding and childhood obesity. A multinational cross‐sectional study of 4,740 children aged 9–11 years was conducted from 12 countries. Infant breastfeeding was recalled by parents or legal guardians. Height, weight, waist circumference, and body fat were obtained using standardized methods. The overall prevalence of obesity, central obesity, and high body fat were 12.3%, 9.9%, and 8.1%, respectively. After adjustment for maternal age at delivery, body mass index (BMI), highest maternal education, history of gestational diabetes, gestational age, and child's age, sex, birth weight, unhealthy diet pattern scores, moderate‐to‐vigorous physical activity, sleeping, and sedentary time, exclusive breastfeeding was associated with lower odds of obesity (odds ratio [OR] 0.76, 95% confidence interval, CI [0.57, 1.00]) and high body fat (OR 0.60, 95% CI [0.43, 0.84]) compared with exclusive formula feeding. The multivariable‐adjusted ORs based on different breastfeeding durations (none, 1–6, 6–12, and > 12 months) were 1.00, 0.74, 0.70, and 0.60 for obesity (P_trend = .020) and 1.00, 0.64, 047, and 0.64 for high body fat (P_trend = .012), respectively. These associations were no longer significant after adjustment for maternal BMI. Breastfeeding may be a protective factor for obesity and high body fat in 9‐ to 11‐year‐old children from 12 countries.

Association between 9-minute walk/run test and obesity among children and adolescents: evidence for criterion-referenced cut-points

Background

Criterion-referenced cut-points for field-based aerobic fitness for children and adolescents are lacking. This study aimed to determine the associations between aerobic fitness and obesity to propose criterion-referenced cut-points for boys and girls (6–17 years).

Methods

A total of 61,465 children and adolescents aged 11.2 ± 2.0 years were recruited from 27 sites (all 26 states and Federal District) across Brazil. Aerobic fitness was assessed using 9-min walk/run test reported as distance attained during the test. Body mass index was calculated from measured height and weight and was used to identify obesity.

Results

The distance covered in the 9-min walk/run test (area under curve > 0.65) had satisfactory predictive ability for obesity. Sensitivity and specificity were moderate (>60%) to strong (>70%) for all age- and sex-specific cut-points. For boys, the optimal physical performance cut-points were, approximately, 1,200 m from 6 to 8 years, 1,300 m from 9 to 11 years, 1,380 m from 12 to 14 years, 1,520 m from 15 to 17 years. For girls, the best cut-points were, approximately, 1,070 m from 6 to 8 years, 1,160 m from 9 to 11 years and 1,200 m from 12 to 17 years.

Conclusions

The 9-min walk/run test had satisfactory predictive ability for obesity in children and adolescents. The physical fitness cut-points proposed in the present study varied according to age and sex and could be useful and practical tools to identify low levels of physical fitness in children and adolescents in Brazil.

Comparing and assessing physical activity guidelines for children and adolescents: a systematic literature review and analysis

Background

The impact of declining physical activity and increased sedentary behaviour in children and adolescents globally prompted the development of national and international physical activity guidelines. This research aims to systematically identify and compare national and international physical activity guidelines for children and adolescents and appraise the quality of the guidelines to promote best practice in guideline development.

Methods

This systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) and reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Only national, or international physical activity and/or sedentary behaviour guidelines were included in the review. Included guidelines targeted children and adolescents aged between 5 and 18 years. A grey literature search was undertaken incorporating electronic databases, custom Google search engines, targeted websites and international expert consultation. Guideline quality was assessed using the Appraisal of Guidelines for Research and Evaluation II Instrument (AGREE II).

Results

The search resulted in 50 national or international guidelines being identified. Twenty-five countries had a national guideline and there were three international guidelines (European Union, Nordic countries (used by Iceland, Norway and Sweden), World Health Organization (WHO)). Nineteen countries and the European Union adopted the WHO guidelines. Guidelines varied in relation to date of release (2008 to 2019), targeted age group, and guideline wording regarding: type, amount, duration, intensity, frequency and total amount of physical activity. Twenty-two countries included sedentary behaviour within the guidelines and three included sleep. Total scores for all domains of the AGREE II assessment for each guideline indicated considerable variability in guideline quality ranging from 25.8 to 95.3%, with similar variability in the six individual domains. Rigorous guideline development is essential to ensure appropriate guidance for population level initiatives.

Conclusions

This review revealed considerable variability between national/international physical activity guideline quality, development and recommendations, highlighting the need for rigorous and transparent guideline development methodologies to ensure appropriate guidance for population-based approaches. Where countries do not have the resources to ensure this level of quality, the adoption or adolopment (framework to review and update guidelines) of the WHO guidelines or guidelines of similar quality is recommended.

Trial registration

Review registration: PROSPERO 2017 CRD42017072558.

Prevalence and correlates of objectively measured weight status among urban and rural Mozambican primary schoolchildren: A cross-sectional study

BACKGROUND

The coexistence of undernutrition (thinness) and overnutrition (overweight/obesity) among children and adolescents is a public health concern in low-middle-income countries. Accurate prevalence estimates of thinness and overweight/obesity among children and adolescents are unavailable in many low-middle-income countries due to lack of data. Here we describe the prevalences and examine correlates of objectively measured weight status among urban and rural schoolchildren in Mozambique.

METHODS

A cross-sectional study design was applied to recruit 9-11-year-old schoolchildren (n = 683) from 17 urban and rural primary schools in Mozambique. Body mass index (BMI) was computed from objectively measured height and weight and participants' weight categories were determined using the World Health Organization cut-points. Actigraph GT3X + accelerometers were worn 24 hours per day for 7 days to assess movement behaviours. Multilevel multivariable modelling was conducted to estimate odds ratios and confidence intervals.

RESULTS

Combined prevalence of overweight/obesity (11.4%) was significantly higher among urban participants compared to rural participants (5.7%; χ2 = 7.1; p = 0.008). Conversely, thinness was more prevalent among rural (6.3%) compared to urban (4.2%) participants. Passive school commute, not meeting daily moderate- to vigorous-intensity physical activity (MVPA) guidelines, and maternal BMI >25 kg/m2 were associated with overweight/obesity while possessing one or more functional cars at home, maternal BMI >25 kg/m2 and being an older participant were associated with thinness in the present sample. The proportion of total variance in the prevalences of obesity and/or thinness occurring at the school level was 8.7% and 8.3%, respectively.

CONCLUSION

Prevalences of thinness, overweight/obesity and other key variables differ between urban and rural schoolchildren in Mozambique. MVPA, active transport and mother's BMI are important modifiable correlates of weight status among Mozambican schoolchildren. Results from this study demonstrate important differences between urban and rural schoolchildren that should not be ignored when designing interventions to manage malnutrition, formulating public health strategies, and interpreting findings.

Clustering of lifestyle risk factors for non-communicable diseases in 304,779 adolescents from 89 countries: A global perspective

The precursors of non-communicable diseases (NCDs) are often manifested during childhood and adolescence with little knowledge about co-occurrence of their related lifestyle risk factors. To address this deficit, we estimated the prevalence and clustering of six major NCD-risk factors in adolescents around the world. Data from the Global School-based Student Health Survey, collected between 2007 and 2016, were analysed in 304,779 adolescents aged 11-17 years (52.2% females) from 89 countries. We compared the observed (O) to expected (E) prevalence ratios of 64 possible combinations of six risk factors to determine their clustering patterns. Overall, 82.4% (95% CI 82.1-82.7) of adolescents had ≥2 risk factors, while 34.9% (34.6-35.3) had ≥3. Adolescents aged 16-17 years, compared to those aged 11-13 years, had higher odds (OR 1.33; 95% CI 1.31-1.36) of reporting ≥3 risk factors. Risk factors clustered in multiple combinations and differed by sex. The clustering of physical inactivity and low fruit and vegetable intake was evident in both males (O/E 1.10; 95% CI 1.07-1.12) and females (1.08; 1.06-1.10). The co-occurrence of cigarette smoking, alcohol drinking, physical inactivity, and low fruit and vegetable intake was 165% greater in females (2.65; 2.28-3.07) and 110% greater in males (2.10; 1.90-2.32) than expected. Globally, adolescents exhibit multiple modifiable risk factors for future development of NCDs. Early gender-specific prevention strategies targeting clusters of lifestyle risk factors should be prioritised to help mitigate future burden of NCDs globally. Periodical collection of behavioural risk factor data should be encouraged to facilitate a sustainable global surveillance.

Outdoor time and dietary patterns in children around the world

Background

Whether outdoor time is linked to dietary patterns of children has yet to be empirically tested. The objective of this study was to examine the association between outdoor time and dietary patterns of children from 12 countries around the world.

Methods

This multinational, cross-sectional study included 6229 children 9-11 years of age. Children self-reported the time that they spent outside before school, after school and on weekends. A composite score was calculated to reflect overall daily outdoor time. Dietary patterns were assessed using a food frequency questionnaire, and two components were used for analysis: healthy and unhealthy dietary pattern scores.

Results

On average, children spent 2.5 h outside per day. After adjusting for age, sex, parental education, moderate-to-vigorous physical activity, screen time and body mass index z-score, greater time spent outdoors was associated with healthier dietary pattern scores. No association was found between outdoor time and unhealthy dietary pattern scores. Similar associations between outdoor time and dietary patterns were observed for boys and girls and across study sites.

Conclusions

Greater time spent outside was associated with a healthier dietary pattern in this international sample of children. Future research should aim to elucidate the mechanisms behind this association.

Fit for School Study protocol: early child growth, health behaviours, nutrition, cardiometabolic risk and developmental determinants of a child's school readiness, a prospective cohort

INTRODUCTION

School readiness is a multidimensional construct that includes cognitive, behavioural and emotional aspects of a child's development. School readiness is strongly associated with a child's future school success and well-being. The Early Development Instrument (EDI) is a reliable and valid teacher-completed tool for assessing school readiness in children at kindergarten age. A substantial knowledge gap exists in understanding how early child growth, health behaviours, nutrition, cardiometabolic risk and development impact school readiness. The primary objective was to determine if growth patterns, measured by body mass index trajectories in healthy children aged 0-5 years, are associated with school readiness at ages 4-6 years (kindergarten age). Secondary objectives were to determine if other health trajectories, including health behaviours, nutrition, cardiometabolic risk and development, are associated with school readiness at ages 4-6 years. This paper presents the Fit for School Study protocol.

METHODS AND ANALYSIS

This is an ongoing prospective cohort study. Parents of children enrolled in the The Applied Health Research Group for Kids (TARGet Kids!) practice-based research network are invited to participate in the Fit for School Study. Child growth, health behaviours, nutrition, cardiometabolic risk and development data are collected annually at health supervision visits and linked to EDI data collected by schools. The primary and secondary analyses will use a two-stage process: (1) latent class growth models will be used to first determine trajectory groups, and (2) generalised linear mixed models will be used to examine the relationship between exposures and EDI results.

ETHICS AND DISSEMINATION

The research ethics boards at The Hospital for Sick Children, Unity Health Toronto and McMaster University approved this study, and research ethics approval was obtained from each school board with a student participating in the study. The findings will be presented locally, nationally and internationally and will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT01869530.

Screen time and problem behaviors in children: exploring the mediating role of sleep duration

Background

Previous research examining the relationship between screen time (ST) and psychological health outcomes have primarily focused on one type of ST (i.e., television), while little research has considered other types of screens (e.g., videos, movies, social media), screen content (e.g., violent video games), or potential mediating variables. Therefore, the purpose of the present study was to assess ST types and content and their association with problem behaviors, and to determine whether these relationships were mediated by sleep duration.

Methods

Parents and children provided cross-sectional baseline data (2016–18) as part of the Adolescent Brain Cognitive Development study, a broadly US representative sample of 11,875 children aged 9 to 10 years. Parents self-reported their children’s emotional and behavioral syndromes via the Child Behavior Checklist and sleep duration using one item from the Parent Sleep Disturbance Scale. Children self-reported their ST behavior, which comprised ST types (television/movies, videos, video games, and social media) and content (mature-rated video games and R-rated movies).

Results

Time spent in various ST types was positively associated with problem behaviors: watching television/movies was associated with a 5.9% increase in rule-breaking behavior (incidence rate ratio [IRR] = 1.059), 5% increase in social problems (IRR = 1.050), 4% increase in aggressive behavior (IRR = 1.040), and 3.7% increase in thought problems (IRR = 1.037). Greater time spent playing mature-rated video games was associated with greater somatic complaints (IRR = 1.041), aggressive behavior (IRR = 1.039), and reduced sleep duration (IRR = .938). Sleep duration mediated the relationship between ST (type and content) and problem behaviors, albeit the effect sizes were small. The largest effects were observed between sleep duration and all problem behaviors, with greater sleep duration predicting an 8.8–16.6% decrease in problem behaviors (IRRs ranging from .834 to .905).

Conclusion

Greater time spent in ST behavior was associated with greater problem behaviors among children. There was strong evidence that longer sleep duration was associated with reduced problem behaviors. While sleep duration mediated the effects of ST on problem behaviors, other potential mediating variables need to be investigated in future research.

Sleep characteristics and health-related quality of life in 9- to 11-year-old children from 12 countries

INTRODUCTION

Previous studies have linked short sleep duration, poor sleep quality, and late sleep timing with lower health-related quality of life (HRQoL) in children. However, almost all studies relied solely on self-reported sleep information, and most studies were conducted in high-income countries. To address these gaps, we studied both device-measured and self-reported sleep characteristics in relation to HRQoL in a sample of children from 12 countries that vary widely in terms of economic and human development.

METHODS

The study sample included 6,626 children aged 9-11 years from Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. Waist-worn actigraphy was used to measure total sleep time, bedtime, wake-up time, and sleep efficiency on both weekdays and weekends. Children also reported ratings of sleep quantity and quality. HRQoL was measured by the KIDSCREEN-10 survey. Multilevel regression models were used to determine the relationships between sleep characteristics and HRQoL.

RESULTS

Results showed considerable variation in sleep characteristics, particularly duration and timing, across study sites. Overall, we found no association between device-measured total sleep time, sleep timing or sleep efficiency, and HRQoL. In contrast, self-reported ratings of poor sleep quantity and quality were associated with HRQoL.

CONCLUSIONS

Self-reported, rather than device-based, measures of sleep are related to HRQoL in children. The discrepancy related to sleep assessment methods highlights the importance of considering both device-measured and self-reported measures of sleep in understanding its health effects.

Prevalence and correlates of adherence to movement guidelines among urban and rural children in Mozambique: a cross-sectional study

Background

Insufficient physical activity, short sleep duration, and excessive recreational screen time are increasing globally. Currently, there are little to no data describing prevalences and correlates of movement behaviours among children in low-middle-income countries. The few available reports do not include both urban and rural respondents, despite the large proportion of rural populations in low-middle-income countries. We compared the prevalence of meeting 24-h movement guidelines and examined correlates of meeting the guidelines in a sample of urban and rural Mozambican schoolchildren.

Methods

This is cross-sectional study of 9–11 year-old children (n = 683) recruited from 10 urban and 7 rural schools in Mozambique. Moderate- to vigorous-intensity physical activity (MVPA) and sleep duration were measured by waist-worn Actigraph GT3X+ accelerometers. Accelerometers were worn 24 h/day for up to 8 days. Recreational screen time was self-reported. Potential correlates of meeting 24-h movement guidelines were directly measured or obtained from validated items of context-adapted questionnaires. Multilevel multivariable logit models were used to determine the correlates of movement behaviours. Meeting 24-h movement guidelines was defined as ≥60 min/day of MVPA, ≤2 h/day of recreational screen time, and between 9 and 11 h/night of sleep.

Results

More rural (17.7%) than urban (3.6%) children met all three 24-h movement guidelines. Mean MVPA was lower (82.9 ± 29.5 min/day) among urban than rural children (96.7 ± 31.8 min/day). Rural children had longer sleep duration (8.9 ± 0.7 h/night) and shorter recreational screen time (2.7 ± 1.9 h/day) than their urban counterparts (8.7 ± 0.9 h/night and 5.0 ± 2.3 h/day respectively). Parental education (OR: 0.37; CI: 0.16–0.87), school location (OR: 0.21; CI: 0.09–0.52), and outdoor time (OR: 0.67; CI: 0.53–0.85) were significant correlates of meeting all three 24-h movement guidelines.

Conclusions

Prevalence and correlates of meeting movement guidelines differed between urban and rural schoolchildren in Mozambique. On average, both groups had higher daily MVPA minutes, shorter sleep duration, and higher recreational screen time than the 24-h movement guidelines recommend. These findings (e.g., higher than recommended mean daily MVPA minutes) differ from those from high-income countries and highlight the need to sample from both urban and rural areas.

Parental support of the Canadian 24-hour movement guidelines for children and youth: prevalence and correlates

BACKGROUND

To explore the prevalence of parental support for meeting the Canadian 24-Hour Movement Guidelines for Children and Youth, identify key interactive support profiles among the four movement behaviors, and investigate subsequent sociodemographic and social cognitive correlates of these profiles.

METHODS

A sample of Canadian parents (N = 1208) with children aged 5 to 17 years completed measures of the theory of planned behavior (TPB), and support of the four child movement behaviors via questionnaire. Differences in the proportion of parents supporting these four health behaviors were explored and demographic and social cognitive (attitude and perceived control) correlates of combinations of parental support for the four health behaviors were evaluated.

RESULTS

Child and youth sleep behavior had the highest parental support (73%) and moderate to vigorous physical activity support had the lowest prevalence (23%). Interactive profiles of the four movement behaviors yielded six primary clusters and comprised wide variation from parents who supported none of these behaviors (19%), to parents who supported all four behaviors (14%). These profiles could be distinguished by the age of the child (younger children had higher support) and the gender of the parent (mothers provided more support), as well as constructs of the TPB, but TPB cognitions were more specific predictors of each health behavior rather than general predictors of aggregate health behavior clusters.

CONCLUSIONS

Teenagers and fathers may represent key targets for parental support intervention of the 24-Hour Movement Guidelines. Intervention content may need to comprise the underlying foundations of attitude and perceived behavioral control to change parental support while considering the unique features of each health behavior to maximize related intervention effectiveness.

Body mass index and movement behaviors among schoolchildren from 13 countries across a continuum of human development indices: A multinational cross-sectional study

OBJECTIVE

This study describes the distributions of body mass index (BMI) and movement behaviors among schoolchildren from 13 countries across a continuum of human development.

METHODS

Data were from a cross-sectional study of 9-11-year-old children (n = 8055) recruited from 269 urban schools in 13 countries, and an additional 7 rural schools in one of these countries (Mozambique). BMI was derived from objectively measured heights and weights. Moderate- to vigorous-intensity physical activity (MVPA), sedentary time (SED), and sleep duration were assessed by waist-worn Actigraph GT3X+ accelerometers. Linear models were used to describe the distributions of BMI z-scores, MVPA, SED, and sleep among sites across varying Human Development Indices (HDIs).

RESULTS

Mean MVPA, SED, and sleep duration were 63.1 ± 27.3 minutes/day, 508.7 ± 72.4 minutes/day, and 8.8 ± 0.9 hours/night, respectively. Overall, 2.1% of the sample were thin, 19.5% overweight, and 11.7% were obese. Density curves (BMI z-scores and SED) for urban children in Mozambique showed significantly higher mean values compared with rural children. Boys had significantly higher mean MVPA compared with girls. Mean BMI z-scores were positively associated (β = .02; P = .004) with HDI, mean daily MVPA minutes were negatively associated (β = -.38; P = .025) with HDI, and mean SED time was positively associated with HDI (β = 1.18; P = .049). No significant association (β = .01; P = .29) was observed between sleep duration and HDI.

CONCLUSION

Our findings show distinct differences in BMI and movement behavior profiles between urban and rural children in Mozambique. Mean BMI z-scores, MVPA, and SED differed by country HDI. These findings support the need to include both rural and urban participants in study samples.

Exploring Parents' Message Receipt and Message Enactment of the World's First Integrated Movement Behaviour Guidelines for Children and Youth

The Canadian 24-Hour Movement Guidelines for Children and Youth are novel in how they integrate the guideline recommendations for the full continuum of movement behaviours, from sleep to vigorous physical activity. Research suggests that the integrated guidelines strategy is perceived favourably, and this study is the first to compare this strategy to traditional segregated guidelines on its effectiveness to disseminate health information. Specifically, this study explored (1) the influence of the integrated guidelines strategy on parents' message receipt and message enactment to support their child meet the guidelines, and (2) the relationship between message receipt and message enactment in a youth movement behaviour context. In this prospective randomized experiment, parents (n= 162) were randomized to read integrated, segregated, or control guidelines and complete pre, post, and 2-week follow-up surveys. Repeated-measures ANOVAs revealed significantly higher message enactment outcomes among participants in the integrated guidelines group (p< .05). Message receipt and enactment outcomes were significantly correlated (r> .171, p< .05). These findings highlight that parents' initial receipt of a message is important for subsequent behaviour change in a youth movement behaviour context. Furthermore, the integrated guidelines strategy may have an advantage in promoting guideline update and should continue to be explored.

Scientific sinkhole: The pernicious price of formatting

Objective

To conduct a time-cost analysis of formatting in scientific publishing.

Design

International, cross-sectional study (one-time survey).

Setting

Internet-based self-report survey, live between September 2018 and January 2019.

Participants

Anyone working in research, science, or academia and who submitted at least one peer-reviewed manuscript for consideration for publication in 2017. Completed surveys were available for 372 participants from 41 countries (60% of respondents were from Canada).

Main outcome measure

Time (hours) and cost (wage per hour x time) associated with formatting a research paper for publication in a peer-reviewed academic journal.

Results

The median annual income category was US$61,000–80,999, and the median number of publications formatted per year was four. Manuscripts required a median of two attempts before they were accepted for publication. The median formatting time was 14 hours per manuscript, or 52 hours per person, per year. This resulted in a median calculated cost of US$477 per manuscript or US$1,908 per person, per year.

Conclusions

To our knowledge, this is the first study to analyze the cost of manuscript formatting in scientific publishing. Our results suggest that scientific formatting represents a loss of 52 hours, costing the equivalent of US$1,908 per researcher per year. These results identify the hidden and pernicious price associated with scientific publishing and provide evidence to advocate for the elimination of strict formatting guidelines, at least prior to acceptance.

24-Hour Movement Behaviors and Impulsivity

BACKGROUND

The objective of this study was to examine individual and concurrent associations between meeting the Canadian 24-Hour Movement Guidelines for Children and Youth (9-11 hours of sleep per night, ≤2 hours of recreational screen time (ST) per day, and at least 60 minutes of moderate to vigorous physical activity per day) and dimensions of impulsivity.

METHODS

Data from this cross-sectional observational study were part of the first annual curated release of the Adolescent Brain Cognitive Development Study. Participants included 4524 children between the ages of 8 and 11 years.

RESULTS

In analyses, it was shown that adherence to individual movement behavior recommendations as well as combinations of adherence to movement behavior recommendations were associated with each dimension of impulsivity. Meeting all 3 movement behavior recommendations was associated with lower positive urgency (95% confidence interval [CI]: -0.12 to -0.05), negative urgency (95% CI: -0.04 to -0.08), Behavioral Inhibition System (95% CI: -0.08 to -0.01), greater perseverance (95% CI: 0.09 to 0.15), and better scores on delay-discounting (95% CI: 0.57 to 0.94). Meeting the ST and sleep recommendations was associated with less impulsive behaviors on all dimensions of impulsivity: negative urgency (95% CI: -0.20 to -0.10), positive urgency (95% CI: -0.16 to -0.08), perseverance (95% CI: 0.06 to 0.15), Behavioral Inhibition System (95% CI: -0.15 to -0.03), Behavioral Activation System (BAS) reward responsiveness (95% CI: -0.04 to -0.05), BAS drive (95% CI: -0.14 to -0.06), BAS fun-seeking (95% CI: -0.15 to -0.17), and delay-discounting task (95% CI: 0.68 to 0.97).

CONCLUSIONS

Findings support efforts to determine if limiting recreational ST while promoting adequate sleep enhances the treatment and prevention of impulsivity-related disorders.

Correlates of Children's Independent Mobility in Canada: A Multi-Site Study

Globally, physical inactivity is a concern, and children’s independent mobility (CIM) may be an important target behavior for addressing the physical inactivity crisis. The aim of this study was to examine correlates of CIM (8–12 years old) in the Canadian context to inform future interventions. CIM was measured via parent surveys. Individual, social, and environmental correlates of CIM were examined using a social–ecological framework. 1699 participants’ data were analyzed using descriptive statistics and gender-stratified linear mixed-effects models while controlling for site, area-level socioeconomic status, and type of urbanization. Individual correlates including child grade (β = 0.612, p < 0.001), language spoken at home (β = −0.503, p < 0.001), car ownership (β = −0.374, p < 0.05), and phone ownership (β = 0.593, p < 0.001) were associated with CIM. For boys, parental gender (β = −0.387, p < 0.01) was negatively associated with CIM. Parents’ perceptions of safety and environment were significantly associated with CIM. Location (i.e., site) was significantly associated with CIM (ref: Trois-Rivières; Ottawa (β = −1.188, p < 0.001); Vancouver (β = −1.216, p < 0.001)). Suburban environments were negatively associated with boys’ independent mobility (β = −0.536, p < 0.05), while walkability (400 m β = 0.064, p < 0.05; 1600 m β = −0.059, p < 0.05) was significantly associated with girls’ independent mobility only. Future research and interventions should consider targeting “modifiable factors” like children’s and parents’ perceptions of neighborhood safety and environment.

Relationships between area-level socioeconomic status and urbanization with active transportation, independent mobility, outdoor time, and physical activity among Canadian children

Background

Active transportation (AT), independent mobility (IM), and outdoor time are promising ways to increase children’s physical activity. However, in order to create interventions to increase those forms of physical activity, it is important to understand the relationships between area-level socioeconomic status (SES) and type of urbanization with AT, IM, outdoor time, and physical activity, and this was the aim of the study.

Methods

One thousand six hundred ninety-nine children in grades 4 to 6 (mean age: 10.2 ± 1.0 years) from three Canadian regions participated. AT, IM, and outdoor time were assessed using questionnaires and physical activity was measured using the SC-StepRX pedometer. Area-level SES was assessed using the median household income of the census tract in which the school was located and type of urbanization was determined for each school using standardized procedures. Generalized linear and general linear mixed models were used to examine the relationships.

Results

Area-level SES and the type of urbanization were generally not related to AT, IM, or physical activity for either gender. However, we observed that both boys and girls living in lower SES areas had decreased odds of spending > 2 h outdoors on weekend days compared to their peers from higher SES areas. Girls living in suburban or rural areas were more likely to spend > 2 h outdoors on weekdays compared to their urban counterparts.

Conclusions

AT, IM, and physical activity are generally not associated with area-level SES or the type of urbanization in this sample of Canadian children. The finding regarding outdoor time showing that both boys and girls of lower SES areas had decreased odds of spending > 2 h outdoors on weekends compared to their peers from higher SES areas suggest that additional efforts should be implemented to offer outdoor play opportunities in lower SES areas.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7420-y) contains supplementary material, which is available to authorized users.

Compositional analyses of the associations between sedentary time, different intensities of physical activity, and cardiometabolic biomarkers among children and youth from the United States

INTRODUCTION

Compositional data analysis is one appropriate method for co-dependent data, even when data are collected for a subdivision of the 24-hour period, such as the waking day. Objectives were to use compositional analyses to examine the combined and relative associations of sedentary time (ST), light-intensity physical activity (LPA), moderate-intensity physical activity (MPA), and vigorous-intensity physical activity (VPA) with cardiometabolic biomarkers in a representative sample of children and youth.

METHODS

This cross-sectional study included 2544 participants aged 6-17 years from the 2003-2006 United States National Health and Nutrition Examination Survey. ST (<100 counts per minute), LPA (100 counts per minute to <4 METs; Freedson age-specific equation), MPA (4 to <7 METs), and VPA (≥7 METs) were accelerometer-derived. Cardiometabolic biomarkers included waist circumference, body mass index (BMI) z-score, HDL-cholesterol, C-reactive protein, and blood pressure. Triglycerides, glucose, insulin, and LDL-cholesterol were measured in a fasting sub-sample of adolescents (n = 670). Compositional linear regression models were conducted.

RESULTS

The composition of ST, LPA, MPA, and VPA was significantly associated with BMI z-score, log waist circumference, systolic and diastolic blood pressure, HDL-cholesterol, and log plasma glucose (variance explained: 1-29%). Relative to the other three behaviors, VPA was negatively associated with BMI z-score (γVPA = -0.206, p = 0.005) and waist circumference (γVPA = -0.03, p = 0.001). Conversely, ST was positively associated with waist circumference (γST = 0.029, p = 0.013). ST and VPA were also positively associated with diastolic blood pressure (γST = 2.700, p = 0.018; γVPA = 1.246, p = 0.038), relative to the other behaviors, whereas negative associations were observed for LPA (γLPA = -2.892, p = 0.026). Finally, VPA was positively associated with HDL-cholesterol, relative to other behaviors (γVPA = 0.058, p<0.001).

CONCLUSIONS

The ST and physical activity composition appears important for many aspects of cardiometabolic health in children and youth. Compositions with more time in higher-intensity activities may be better for some aspects of cardiometabolic health.

The association between physical fitness and health in a nationally representative sample of Canadian children and youth aged 6 to 17 years

INTRODUCTION

This study explored the relationship between physical fitness and indicators of physical and psychosocial health in a nationally representative sample of Canadian children and youth aged 6-17 years.

METHODS

We conducted a secondary data analysis of Canadian Health Measures Survey (Cycles 1 and 2; 2007-2011) data. The physical fitness measures included cardiorespiratory fitness (CRF; modified Canadian Aerobic Fitness Test), strength (handgrip strength), flexibility (sit-and-reach), and muscular endurance (partial curl-ups). The physical health indicators included directly measured biomarkers (total and HDL [high-density lipoprotein] cholesterol, C-reactive protein, glucose, and HbA1c [glycohaemoglobin]) and measures of adiposity, resting heart rate, and blood pressure. Psychosocial health was assessed using the Strengths and Difficulties Questionnaire. Multiple linear regressions were used to determine the association between variables, stratified by age groups and sex.

RESULTS

3,800 (48.9% female) children and youth were retained for this analysis. CRF displayed significant favourable associations with most physical health indicators in male and female participants. There were less significant favourable associations with flexibility and muscular endurance compared with CRF across age and sex groups. Strength was associated with higher adiposity in males and females, and lower heart rate in male children (β = -1.9; 95% CI: -2.9, -1.0) and female youth (β = -2.0; 95% CI: -2.7, -1.2). There were few significant favourable associations between measures of physical fitness and psychosocial health in this sample of children and youth.

CONCLUSION

These findings suggest that physical fitness, and especially CRF, is a significant indicator of physical health among Canadian children and youth aged 6-17 years.