Non-school Days Research Articles

Exploring differential trends in severe and fatal child pedestrian injury in New South Wales, Australia (1997–2006)

The study explores trends in severe and fatal child pedestrian injuries in New South Wales (NSW), over the 10-year period 1997–2006, in comparison to adults and for various subgroups. Data on pedestrian injury (reported as fatalities or hospitalisations) were obtained from the Traffic Accident Database System (TADS; Roads and Traffic Authority of New South Wales) which captures road traffic events reported to police, and from the NSW Admitted Patients Data Collection (APDC) which captures all hospital inpatient separations. Annual percentage changes in injury counts and rates were compared using Poisson regression. A substantial drop in the pedestrian injury rate was observed; however, the rate of decline was steeper for children (aged less than 15 years) than for adults. The drop in child pedestrian injury was manifest in both the police report data and the hospital admission data. The annual percentage decrease was significantly greater for boys than for girls, and the three major urban centres compared with elsewhere in the state. No differences were detected in the annual rate decrease between school days and non-school days (a proxy for safe school zones), or between different road types (a proxy for restricted speed limits). Past research suggests that injury rate reductions are not solely due to decreased exposure. There remains, however, limited data on the extent of pedestrian mobility. Differences in relative reduction in pedestrian injury rates suggest a differential benefit arising from road safety initiatives.

Abstract 1824: Sun exposure and the risk of malignant lymphoma in an Asian population: The Singapore Lymphoma Study

Abstract INTRODUCTION Recent epidemiological studies have reported an inverse association between sun exposure and Non-Hodgkin lymphoma (NHL) which may be related to vitamin D or other factors, but these studies have been conducted almost exclusively in the Western countries, and in temperate locations. METHODS The Singapore Lymphoma Study is a hospital-based, case-control study conducted in Singapore between Feb 2005 and Dec 2008. Singapore residents (men and women, ethnic Chinese/Malays/Indians) aged 18 to 90 formed the study population. Detailed information on outdoor activities under sun (for recreational or occupational purposes) during childhood and in adulthood, skin colour and sun sensitivity, and other information on other possible risk factors were collected in personal interviews. A total of 543 incident malignant lymphomas including 74 Hodgkin's lymphoma (HL), 403 B-cell and 61 T and NK-cell NHL and 5 others, and 830 controls were recruited. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression analysis, adjusted for age, gender, ethnicity, and housing types as surrogate for social economic status. RESULTS Skin colour and sun sensitivity did not show any association with risk of malignant lymphoma, after adjusting for ethnicity. We observed a reduced overall risk of NHL (but not HL) among subjects who reported spending time outdoors regularly, especially on weekends/rest days. A lower risk of NHL was associated with recreational sun exposure in childhood non-school days (OR 0.7, 95% CI 0.5-0.9) and in adulthood weekends/rest days (OR 0.8, 95%CI 0.6-1.0), and the observed association was significant in females when stratified by gender. In addition, occupational sun exposure in males was inversely associated with the risk of NHL (OR 0.7, 95%CI 0.5-1.0). Cumulative working time outside under sun appeared unrelated to NHL overall. The associations were more consistently observed in B-cell NHL subtypes (OR 0.6, 95%CI 0.5-0.8), in diffuse large B-cell lymphoma (OR 0.6, 95%CI 0.5-0.9) and mucosal-associated lymphoid tissue lymphoma (OR 0.5, 95%CI 0.2-1.0), than in T-cell NHL. CONCLUSION As the first case-control lymphoma study in Asia, our data are consistent with an inverse association between intermittent sun exposure and NHL in this study population. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1824.

Day type and the relationship between weight status and sleep duration in children and adolescents

This study aimed to explore sleep duration in young Australians on different types of days across weight classes. Use of time and anthropometric data were collected on 8,866 nights from 3,884 9-18 year old Australians. The association between sleep duration and weight status was examined using factorial ANOVA for four day types: S-S (to bed and waking on school days); S-NS (to bed on school day and waking on non-school day); NS-NS (to bed and waking on non-school days); NS-S (to bed on non-school day and waking on school day). Sleep duration varied with weight status when all day types were considered together (p=0.0012). Obese adolescents slept less than normal and underweight adolescents. However, the relationship varied for different day types; with the strongest relationship for NS-S days (on which obese children slept 65 min less than very underweight children, p<0.0001). The association between weight status and sleep duration showed consistent gradients across weight categories, but only for certain day types. These patterns cast light on the direction of causation in the obesity-sleep duration relationship. Findings suggest that short sleep duration contributes to obesity, or that a third unidentified factor has an impact on both.

The relationships between sex, age, geography and time in bed in adolescents: A meta-analysis of data from 23 countries

To quantify the relationships between age, sex and country of residence and sleep time (time in bed) in young people aged 9-18 years. Thirty studies of sleep patterns in healthy adolescents from the last 30 years in 20 countries were reviewed. Monte Carlo simulation generated pseudo-data where only summary statistics were available. Raw and pseudo-data were combined, generating a total of 92,977 data points. A mixed model, clustering on countries, analysed data for school and non-school days separately. Sleep time varied with sex, age and geographical region. School day sleep differed slightly between boys and girls, girls sleeping 11min/night more than boys (p=0.003). On non-school days, girls slept 29min more each day (p=0.003). Sleep time declined with age, - 14min/day per year of age (school days), and seven min/night per year of age (non-school days). Large differences between countries, showed adolescents from Asian countries sleeping 40-60min less each night than Americans, and 60-120min less than Europeans. Sex, age, geographical region and day type interact and predict sleep patterns in adolescents. One consistent trend is the increasing gap between sleep on school days and non-school days as adolescents get older.

Time to Work or Time to Play: The Effect of Student Employment on Homework, Sleep, and Screen Time

Abstract We use detailed time-diary information on high school students’ daily activities from the 2003–2008 American Time Use Surveys (ATUS) to investigate the effects of employment on the time a student spends on homework and other major activities. Time-diary data are more detailed and accurate than data derived from responses to “usual activity” survey questions underlying other analyses and capture the immediate effects of working that may well accumulate over time to affect future outcomes. Our results suggest that employment decreases the time that high school students spend on homework, which is human-capital building, on all days, but also decreases screen time on non-school days, which may be considered unproductive time. Employed teens get more than the recommended amount of sleep on school days, and only slightly less on non-school days.

Nutrients and foods consumed by New Zealand children on school days and non-school days

Nutrients and foods consumed by New Zealand children on school days and non-school days

Child welfare programs and child nutrition: Evidence from a mandated school meal program in India

Utilizing the data I collected on a nationally mandated school meal program in India, I examine the extent to which children benefit from the targeted public transfer. Relying upon built-in randomness in whether a child's 24-hour food consumption recall was for a school or non-school day, I find that the daily nutrient intake of program participants increased substantially by 49% to 100% of the transfers. The results are robust to the potential endogeneity of program placement and individual participation. The findings suggest that for as low a cost as 3 cents per child per school day the scheme reduced the daily protein deficiency of a primary school student by 100%, the calorie deficiency by almost 30% and the daily iron deficiency by nearly 10%. At least in the short-run, therefore, the program had a substantial effect on reducing hunger at school and protein–energy malnutrition.

Sleep and waking in US adolescents

Time diary analysis was performed using cohort data from 1981 and the period 2003-2006 by Knutson and Lauderdale from the University of Chicago. The results show that bed times and wake times were similar in 1981 and 2003-2006. Average time in bed on school days was about 8 hours and 9-10 on non-school days. The greatest predictor of wake time was school start time. Many adolescents spent less than the recommended 9 hours per day in bed on school days. Increased computer use and earlier start school days may contribute to the wide spread lack of adequate sleep among US adolescents.

Sociodemographic and Behavioral Predictors of Bed Time and Wake Time among US Adolescents Aged 15 to 17 Years

To examine bed times and wake times in US adolescents aged 15 to 17 years using time diaries to determine whether adolescent sleep has changed in recent years and what factors determine bed times and wake times. Time diary analysis using 2 national probability samples: 1981 Time Use Longitudinal Panel Study (n = 130) and 2003-2006 American Time Use Survey (n = 2978). Average time in bed on school days was about 8 hours and was 1 to 2 hours longer on non-school days. Bed times and wake times were similar in 1981 and 2003-2006. Sociodemographic factors and daytime activities, specifically computer use and social activities, predicted bed time. On school days, school start time was the strongest predictor of wake time. Every hour earlier that school started, wake time was about 25 minutes earlier. Adolescents spent less than the recommended 9 hours in bed on school days. There is no evidence that this is a recent change in bed times and wake times, however. Although many factors influence bed time, school start time is the strongest determinant of wake time on school days. Increased computer use and earlier school days may be contributing to insufficient sleep in adolescents.

Characterization of fine particulate matter in Ohio: Indoor, outdoor, and personal exposures

Ambient, indoor, and personal PM 2.5 concentrations were assessed based on an exhaustive study of PM 2.5 performed in Ohio from 1999 to 2000. Locations in Columbus, one in an urban corridor and the other in a suburban area were involved. A third rural location in Athens, Ohio, was also established. At all three locations, elementary schools were utilized to determine outdoor, indoor, and personal PM 2.5 concentrations for fourth and fifth grade students using filter-based measurements. Three groups of 30 students each were used for personal sampling at each school. Continuous ambient PM 2.5 mass concentrations were also measured with tapered element oscillating microbalances (TEOMs). At all three sites, personal and indoor PM 2.5 concentrations exceeded outdoor levels. This trend is consistent on all week days and most evident in the spring as compared to fall and winter. The ambient PM 2.5 concentrations were similar among the three sites, suggesting the existence of a common regional source influence. At all the three sites, larger variations were found in personal and indoor PM 2.5 than ambient levels. The strongest correlations were found between indoor and personal concentrations, indicating that personal PM 2.5 exposures were significantly affected by indoor PM 2.5 than by ambient PM 2.5. This was further confirmed by the indoor to outdoor (I/O) ratios of PM 2.5 concentrations, which were greater when school was in session than non-school days when the students were absent.

Comparison between reported and recorded total sleep time and sleep latency in 6- to 11-year-old children: the Tucson Children’s Assessment of Sleep Apnea Study (TuCASA)

Research comparing parental report of sleep times to objectively obtained polysomnographic evidence of sleep times in schoolchildren is lacking. This report compares habitual sleep time and objectively recorded sleep time and sleep latency with parental reports of sleep time immediately after a night of polysomnography in elementary schoolchildren. Unattended home polysomnograms (PSG) were obtained from 480 children. On the night of the PSG, a parent was asked to complete a Sleep Habits Questionnaire, which inquired about the habitual total sleep time (HABTST) and habitual sleep onset latency (HABSOL) of his/her child on both school days and nonschool days. On the morning after the PSG, the parent was asked to estimate the total sleep time (ESTTST) and sleep onset latency (ESTSOL) of his/her child on the night of the recording. Comparisons were made to actual total sleep time (PSGTST) and sleep latency (PSGSOL) on the PSG. The sample was comprised of 50% girls, 42.3% Hispanic, and 53% aged 6-8 years. The mean HABTST, ESTTST, and PSGTST were 578, 547, and 480 min, respectively. HABTST was greater than both ESTST and PSGTST (p < 0.001). Moreover, ESTTST was greater than PSGTST (p < 0.001). The mean HABSOL, ESTSOL, and PSGSOL were 15, 17, and 11 min. ESTSOL was longer than PSGSOL (p < 0.001). There were no gender differences. However, Hispanic parents reported significantly less HABTST in their children than Caucasian parents (566 vs 587 min, p < 0.001). Parents of schoolchildren in this population-based sample substantially overestimated their children's actual total sleep time and sleep onset latency.

Psychosocial and Environmental Correlates of Adolescent Sedentary Behaviors

To determine correlates of sedentary behaviors in adolescents through the examination of psychosocial and environmental variables. The study used a cross-sectional design to evaluate an ethnically diverse clinic-based sample of 878 adolescents who were 11 to 15 years old. Bivariate and multivariate analyses were stratified by gender to assess correlates of sedentary behaviors occurring on the most recent nonschool day (television viewing, computer video games, sitting listening to music, and talking on the phone). For girls, age, family support, television/video rules, and hills in the neighborhood were associated with sedentary behaviors. Furthermore, psychological constructs such as self-efficacy, enjoyment, change strategies, and pros and cons of change emerged as correlates of sedentary behaviors. A moderator effect revealed that the proportion of girls in the low-BMI group decreased with increased self-efficacy, whereas the proportion of girls in the high-BMI group did not vary significantly by self-efficacy. For boys, age, ethnicity, BMI, cons of change, and self-efficacy were associated with sedentary behaviors. This study provides evidence of factors associated and not associated with adolescent sedentary behaviors. Similar to physical activity, measures of specific psychosocial constructs of sedentary behavior demonstrated important associations. The results highlight the need for additional examination of the correlates of sedentary behavior to determine which correlates are mechanisms of behavior change.

Adolescents’ Health and Well-being in the United Kingdom

The life style and social behaviour of young people plays a critical role in determining the health of the population in the adult stages of the life cycle. In this article, data from the UK 2000 Time Use Survey are examined in an attempt to better understand relationships between adolescent time use, well-being and health in the UK. The time use of the 12–19 years olds is examined as a function of gender, age, day of the week, and household composition (single parent and two parent households). The time of the day when particular activities take place is investigated. This enables us to identify activities which go on late in the evening and to distinguish between sleep patterns on school days and non-school days. The amounts of time adolescents spend alone compared to time spent with “others” and time travelling on foot compared with travelling by car is examined. Analyses of adolescents’ feelings of being rushed, feeling healthy, and teens’ participation in sporting and cultural activities also form part of the analyses reported in this article.

Work, Rest and Leisure – Trends in Late Adolescent Time Use in Australia in the 1990S

Although how teenagers spend their days is fundamentally linked to their psychological and physiological well-being, the analysis of their actual time use is very limited. This paper aims to provide a profile of how young people in late adolescence (between the ages of 15 to 19) spent their time at the end of the 20th century in Australia. The way adolescents spent their school and non-school days in work, rest and leisure were examined using two national time use surveys. Changes in the time use of young people in late adolescence were investigated for the five-year period from 1992 to 1997 in the attempt to find out whether teenagers were working harder and resting or engaging in leisure less. Although Australian teenagers in the late 1990s were spending less time working and more time at leisure, the type of activities they were spending their free time on (watching television and playing computer games) may have a negative impact on their health and well-being.

Utilizing parental feedback for summer lunch program needs

TEXT: School lunch is often the only nutritious meal children receive. When children are not in school, the risk of hunger and poor nutrition increases. Parents are responsible for non-school day meals, thus they are a customer for summer lunch programs. This research explored parents’ needs for their children in a California county where summer lunch was seldom offered. Four elementary schools, eligible for free school lunch, participated. Of the 3100 surveys sent home with children, 18% (n 555) responded. The majority of parents communicated in Spanish (54%). Many siblings were also eligible for free lunch (n 993). The majority were interested in summer lunch (74%). Most children (89%) stayed home during the summer. Slightly less than half (47%) indicated children would miss a lunch meal. Parents described a typical home lunch. Only 20% included milk and only 15% included a fruit/vegetable. Provision of protein foods varied: 36% of the lunch menus included a high fat protein and 12% included a lower fat protein. However, 52% of the menus did not include a protein source. The greatest concern parents had about a summer lunch program was adult supervision and/or transportation to a lunch site. The majority of parents preferred a lunch site at their children’s school (54%) or at a neighborhood park/community center (34%). The data suggests incorporating feedback assists in projecting potential strengths and challenges when planning and promoting a summer lunch program. Research data was used to assist with community strategic planning.

Cortisol and behavior in fragile X syndrome

The purpose of this study was to determine if children with fragile X syndrome, who typically demonstrate a neurobehavioral phenotype that includes social anxiety, withdrawal, and hyper-arousal, have increased levels of cortisol, a hormone associated with stress. The relevance of adrenocortical activity to the fragile X phenotype also was examined. One hundred and nine children with the fragile X full mutation (70 males and 39 females) and their unaffected siblings (51 males and 58 females) completed an in-home evaluation including a cognitive assessment and a structured social challenge task. Multiple samples of salivary cortisol were collected throughout the evaluation day and on two typical non-school days. Measures of the fragile X mental retardation (FMR1) gene, child intelligence, the quality of the home environment, parental psychopathology, and the effectiveness of educational and therapeutic services also were collected. Linear mixed-effects analyses were used to examine differences in cortisol associated with the fragile X diagnosis and gender (fixed effects) and to estimate individual subject and familial variation (random effects) in cortisol hormone levels. Hierarchical multiple regression analyses were conducted to determine whether adrenocortical activity is associated with behavior problems after controlling for significant genetic and environmental factors. Results showed that children with fragile X, especially males, had higher levels of salivary cortisol on typical days and during the evaluation. Highly significant family effects on salivary cortisol were detected, consistent with previous work documenting genetic and environmental influences on adrenocortical activity. Increased cortisol was significantly associated with behavior problems in boys and girls with fragile X but not in their unaffected siblings. These results provide evidence that the function of the hypothalamic-pituitary-adrenal axis may have an independent association with behavioral problems in children with fragile X syndrome.

The influence of physical activity, socioeconomic status, and ethnicity on the weight status of adolescents.

This study examined the effects of physical activity, television viewing, video game play, socioeconomic status (SES), and ethnicity on body mass index (BMI). The sample was 2389 adolescents, 10 to 16 years of age (12.7 +/- 1.0 years); 1240 (52%) females and 1149 (48%) males; 77% white and 23% African American; from rural (77%) and urban (23%) settings. BMI and skinfolds were directly assessed. All other data were obtained from questionnaires. Watching television on non-school days was related to being overweight (p < 0.005). However, when BMI analyses were adjusted for ethnicity and SES, there were no significant effects of television viewing on BMI (p > 0.061). Increased hours of video game play enhanced the risk of being overweight for both genders when analyses were adjusted for ethnicity and SES (p < 0.019). In males, participation in as little as one high-intensity physical activity 3 to 5 days a week decreased the ethnic- and SES-adjusted relative risk of being overweight (RR = 0.646; CI: 0.427 to 0.977). For females, the ethnic- and SES-adjusted relative risk for being overweight was not significantly altered by physical activity. The logistic analyses further indicated the influence of low SES and African American ethnicity overshadowed any direct effect of television or videos. Because weight status of male adolescents appears to be more related to exercise habits than to television or video game habits, increased participation in high-intensity exercise appears to be important. For females, neither videos nor exercise habits appear to be related to risk of being overweight. However, ethnicity and SES may be important factors that can influence body weight status, while television viewing may be of some importance. Thus, programs to reduce obesity in female adolescent should focus their efforts in lower SES communities.

The Relationship among Television Watching, Physical Activity, and Body Composition of 5- or 6-Year-Old Children

This follow-up investigation examined the relationship among observed time of television watching, physical activity, and body composition in 5- to 6-year-old children previously studied 2 years ago. Activity level on school and nonschool days was measured with the Children’s Activity Rating Scale. Television watching time was assessed by direct observation, and body composition was measured with the body mass index, skinfold thicknesses, and waist/hip ratio. Television watching behavior, which increased from the earlier study, was not associated with body composition. Physical activity was lower during television watching than nontelevision watching time.

Sleep characteristics of adolescents: A longitudinal study

The aim of the present research was to study sleep/wake cycle parameters of adolescents and to examine biologic and social influences on their changing sleep patterns. This was a longitudinal study of sleep characteristics of a group of 66 adolescents (mean age, 13 years and 6 months). The adolescents underwent a physical examination, had their pubertal development classified according to Tanner stages, and answered a sleep questionnaire on three timepoints at 6-month intervals. Sleep onset occurred about 1.0 hr later, wake-up time about 3.0 hr later, and sleep length was 1.0-1.5 hr longer on weekends when compared with weekdays. About 60% of the adolescents reported daytime sleepiness, mainly from 8:00 a.m. to 10:00 a.m. and from 2:00 p.m. to 4:00 p.m. on school days. Morning sleepiness on school days occurred at a time of the day that corresponded to sleep on non-school days. Additionally, there was a displacement toward later hours of the wake-up time and a sleep-length increase during weekends from the first to the third timepoint. Social factors such as home conditions and scheduling of school and non-school activities did not change throughout the period of pubertal development studied. Changes of sleep patterns detected may therefore represent an ontogenetic trend along puberty.

Using longitudinal data to understand children's activity patterns in an exposure context: Data from the Kanawha county health study

An important component of assessing the levels, the sources, and the health effects of children's exposure to air pollution is understanding how and where members of this sensitive population spend their time. There are, however, few data bases that allow the documentation of the day-to-day nature of children's activities. Of particular concern is whether the one-day snapshots provided by time/activity diaries typically used in exposure studies represent the actual temporal and spatial extent of children's activities. As part of a community health study, longitudinal data on children's time/activity patterns were recently collected. A respiratory health status and gender stratified sample of 90 children kept daily diaries over two-week periods during both the summer and the fall. This paper first presents baseline information of children's activity patterns: the sample distribution of time spent in each of five microenvironments (travel, outdoor, at school, at home, and inside other locations) and the daily temporal pattern of activities. The consistent patterns of children on school days suggest that for most days we can accurately predict children's locations by time of day. The second part of the analysis shows that there is both high child-to-child variation in the average time spent in each microenvironment, even after controlling for gender and respiratory health status, and strong temporal variability in activity patterns within a child over time, even after controlling for school days versus nonschool days.