State-level estimates of childhood obesity prevalence in the United States corrected for report bias.

BACKGROUND/OBJECTIVES: State-specific obesity prevalence data are critical to public health efforts to address the childhood obesity epidemic. However, few states administer objectively measured body mass index (BMI) surveillance programs. This study reports state-specific childhood obesity prevalence by age and sex correcting for parent-reported child height and weight bias. SUBJECTS/METHODS: As part of the Childhood Obesity Intervention Cost Effectiveness Study (CHOICES), we developed childhood obesity prevalence estimates for states for the period 2005-2010 using data from the 2010 US Census and American Community Survey (ACS), 2003-2004 and 2007-2008 National Survey of Children's Health (NSCH) (n=133 213), and 2005-2010 National Health and Nutrition Examination Surveys (NHANES) (n=9377; ages 2-17). Measured height and weight data from NHANES were used to correct parent-report bias in NSCH using a non-parametric statistical matching algorithm. Model estimates were validated against surveillance data from five states (AR, FL, MA, PA and TN) that conduct censuses of children across a range of grades. RESULTS: Parent-reported height and weight resulted in the largest overestimation of childhood obesity in males ages 2-5 years (NSCH: 42.36% vs NHANES: 11.44%). The CHOICES model estimates for this group (12.81%) and for all age and sex categories were not statistically different from NHANES. Our modeled obesity prevalence aligned closely with measured data from five validation states, with a 0.64 percentage point mean difference (range: 0.23-1.39) and a high correlation coefficient (r=0.96, P=0.009). Estimated state-specific childhood obesity prevalence ranged from 11.0 to 20.4%. CONCLUSION: Uncorrected estimates of childhood obesity prevalence from NSCH vary widely from measured national data, from a 278% overestimate among males aged 2-5 years to a 44% underestimate among females aged 14-17 years. This study demonstrates the validity of the CHOICES matching methods to correct the bias of parent-reported BMI data and highlights the need for public release of more recent data from the 2011 to 2012 NSCH.

The academic penalty for gaining weight: a longitudinal, change-in-change analysis of BMI and perceived academic ability in middle school students.

BACKGROUND/OBJECTIVES: Worse educational outcomes for obese children regardless of academic ability may begin early in the life course. This study tested whether an increase in children's relative weight predicted lower teacher- and child-perceived academic ability even after adjusting for standardized test scores. SUBJECTS/METHODS: Three thousand three hundred and sixty-two children participating in the Early Childhood Longitudinal Study-Kindergarten Cohort were studied longitudinally from fifth to eighth grade. Heights, weights, standardized test scores in maths and reading, and teacher and self-ratings of ability in maths and reading were measured at each wave. Longitudinal, within-child linear regression models estimated the impact of a change in body mass index (BMI) z-score on change in normalized teacher and student ratings of ability in reading and maths, adjusting for test score. RESULTS: A change in BMI z-score from fifth to eighth grade was not independently associated with a change in standardized test scores. However, adjusting for standardized test scores, an increasing BMI z-score was associated with significant reductions in teacher's perceptions of girls' ability in reading (-0.12, 95% confidence interval (CI): -0.23, -0.03, P=0.03) and boys' ability in math (-0.30, 95% CI: -0.43, -0.17, P<0.001). Among children who were overweight at fifth grade and increased in BMI z-score, there were even larger reductions in teacher ratings for boys' reading ability (-0.37, 95% CI: -0.71, -0.03, P=0.03) and in girls' self-ratings of maths ability (-0.47, 95% CI: -0.83, -0.11, P=0.01). CONCLUSIONS: From fifth to eighth grade, increase in BMI z-score was significantly associated with worsening teacher perceptions of academic ability for both boys and girls, regardless of objectively measured ability (standardized test scores). Future research should examine potential interventions to reduce bias and promote positive school climate.

Simulation models of obesity: a review of the literature and implications for research and policy.

Simulation models (SMs) combine information from a variety of sources to provide a useful tool for examining how the effects of obesity unfold over time and impact population health. SMs can aid in the understanding of the complex interaction of the drivers of diet and activity and their relation to health outcomes. As emphasized in a recently released report of the Institute or Medicine, SMs can be especially useful for considering the potential impact of an array of policies that will be required to tackle the obesity problem. The purpose of this paper is to present an overview of existing SMs for obesity. First, a background section introduces the different types of models, explains how models are constructed, shows the utility of SMs and discusses their strengths and weaknesses. Using these typologies, we then briefly review extant obesity SMs. We categorize these models according to their focus: health and economic outcomes, trends in obesity as a function of past trends, physiologically based behavioural models, environmental contributors to obesity and policy interventions. Finally, we suggest directions for future research.

Total energy intake, adolescent discretionary behaviors and the energy gap.

OBJECTIVE: To estimate total energy intake and the energy gap-the daily imbalance between energy intake and expenditure-associated with discretionary behaviors of adolescents, namely their leisure active behaviors (playing or participating in sports and heavy chores), leisure sedentary behaviors (television (TV) viewing and playing video and computer games), productive sedentary behaviors (reading or doing homework). DESIGN: Prospective observational study. PARTICIPANTS: A total of 538 students (mean age at baseline=11.7 years) from public schools in the Boston area studied prospectively from the fall of 1995 to the spring of 1997. MEASUREMENTS: Anthropometric assessment including height and weight, dietary assessment using a youth food frequency questionnaire and measures of TV, video, reading/doing homework and youth physical activity. RESULTS: We estimate the change in total energy intake for each hour change in discretionary activity using regression methods. A 1-h increase in watching TV is associated with a 106 kcal h(-1) increase in total energy intake (95% confidence interval (CI): 61-150 kcal day(-1)). A similar change of 92 kcal h(-1) (95% CI: 37-147 kcal day(-1)) is seen with playing video and computer games. The change in energy intake associated with an hour change in physical activity is 292 kcal h(-1) (95% CI: 262-321 kcal day(-1)). No significant change is associated with reading/doing homework. Assuming that typical energy expenditures are associated with these behaviors, reading/doing homework appears to be an 'energy neutral' activity, whereas watching TV and playing video and computer games is associated with an energy surplus. If we assume that physical activity levels are moderate (3.5 METs), then this is also an energy surplus activity. If physical activity is assumed to be vigorous for the entire time allotted (>6.0 METs), an energy deficit could be achieved. We validated these estimates by calculating regressions predicting change in weight. Results indicate that each hour increase in TV viewing is associated with a weight increase of 0.38 kg (95% CI: 0.17-0.59 kg), with no significant associations for the other behaviors. A model with change in BMI as the dependent variable produced similar results. CONCLUSION: Watching TV is an activity associated with a daily energy surplus. Although physical activity is thought of as an energy deficit activity, our estimates do not support this hypothesis. Reading/doing homework is the only discretionary activity examined which appears to be clearly energy neutral. The differential impacts of these discretionary behaviors on energy intake and the energy gap are discussed in relation to food-related advertisements aimed at children and adolescents.

Relationship power, condom use and HIV risk among women in the USA.

Women's ability to negotiate safer sexual practices, particularly condom use, is a vital component of HIV/STD prevention strategies. Gender-based power imbalances may constrain women's negotiation ability, yet few empirical studies have tested the hypothesis that sexual relationship power constitutes a key factor in condom use negotiation. In this investigation, a new measure - the Sexual Relationship Power Scale (SRPS) - was applied. Data were collected from 388, mostly Latina, women at an urban community health centre in Massachusetts. Women with high levels of relationship power were five times as likely as women with low levels to report consistent condom use, after controlling for sociodemographic and psychosocial variables (p < 0.05). Population attributable risk estimates indicate that 52% of the lack of consistent condom use among women can be attributed to low sexual relationship power. The strong association between the Sexual Relationship Power Scale and consistent condom use supports the hypothesis that relationship power plays a key role in safer sex decision making. These findings underscore the importance of including the issue of relationship power in the design and implementation of programmes that promote sexual and reproductive health, as well as research investigating condom use and HIV risk.

Who cares for medicaid-enrolled children with chronic conditions?

OBJECTIVE: To estimate generalist, pediatric subspecialist, and any subspecialist use by Medicaid-enrolled children with chronic conditions and to determine the correlates of use. METHODS: We analyzed Medicaid claims data collected from 1989 to 1992 from 4 states for 57 328 children and adolescents with 11 chronic conditions. We calculated annual rates of generalist, subspecialist, and pediatric subspecialist use. We used logistic regression to determine the association of demographics, urban residence, and case-mix (Adjusted Clinical Groups) with the use of relevant pediatric and any subspecialist care. RESULTS: Most children with chronic conditions had visits to generalists (range per condition: 78%-90% for children with Supplemental Security Income [SSI] and 85%-94% for children without SSI) during the year studied. Fewer children visited any relevant subspecialists (24%-59% for children with SSI and 13%-56% for children without SSI) or relevant pediatric subspecialists (10%-53% for children with SSI and 3%-37% for children without SSI). In general, children who were more likely to use pediatric subspecialists were younger, lived in urban areas, were white (only significant for non-SSI children), and had higher Adjusted Clinical Groups scores. Use of any subspecialists followed a similar pattern except that urban residence is statistically significant only for children with SSI and the youngest age group does not differ from the oldest age group for children without SSI. CONCLUSIONS: Children who had chronic conditions and were enrolled in Medicaid received a majority of their care from generalist physicians. For most conditions, a majority of children did not receive any relevant subspecialty care during the year and many of these children did not receive care form providers with pediatric-specific training.

Extrarelational sex among Mexican men and their partners' risk of HIV and other sexually transmitted diseases.

OBJECTIVES: This study explored the risk of HIV and other sexually transmitted diseases (STDs) among married and cohabiting women in Mexico City, Mexico, derived from their partners' sexual behaviors. METHODS: Results were derived from the first population-based household survey in Mexico that investigated male sexual behavior. Analyses were restricted to sexually active married or cohabiting men (n = 3990). RESULTS: Fifteen percent of the men reported extrarelational sex during the past year, 9% reported condom use during last intercourse, and 80% perceived no HIV risk. Most secondary partners were coworkers, mistresses, or friends. CONCLUSIONS: Targeted HIV and STD prevention efforts appear necessary because a substantial number of women may be at risk.

Relation between consumption of sugar-sweetened drinks and childhood obesity: a prospective, observational analysis.

BACKGROUND: The rising prevalence of obesity in children has been linked in part to the consumption of sugar-sweetened drinks. Our aim was to examine this relation. METHODS: We enrolled 548 ethnically diverse schoolchildren (age 11.7 years, SD 0.8) from public schools in four Massachusetts communities, and studied them prospectively for 19 months from October, 1995, to May, 1997. We examined the association between baseline and change in consumption of sugar-sweetened drinks (the independent variables), and difference in measures of obesity, with linear and logistic regression analyses adjusted for potentially confounding variables and clustering of results within schools. FINDINGS: For each additional serving of sugar-sweetened drink consumed, both body mass index (BMI) (mean 0.24 kg/m2; 95% CI 0.10-0.39; p=0.03) and frequency of obesity (odds ratio 1.60; 95% CI 1.14-2.24; p=0.02) increased after adjustment for anthropometric, demographic, dietary, and lifestyle variables. Baseline consumption of sugar-sweetened drinks was also independently associated with change in BMI (mean 0.18 kg/m2 for each daily serving; 95% CI 0.09-0.27; p=0.02). INTERPRETATION: Consumption of sugar-sweetened drinks is associated with obesity in children.

Preventing obesity in children and adolescents.

In this review, we address the natural history of obesity in children, the most promising family- and school-based approaches to the prevention of obesity, and the barriers and opportunities associated with secondary prevention. In childhood, the most important periods of risk appear to be the periods of adiposity rebound and adolescence. Caution regarding the period of adiposity rebound is still warranted, because it is not yet clear that early rebound is attributable to changes in body fat. Families and schools represent the most important foci for preventive efforts in children and adolescents. One productive approach is to proceed from an examination of factors that affect energy balance to the identification of more proximal influences on those factors. This approach may help to narrow the strategies necessary to prevent or treat childhood obesity. For example, television viewing affects both energy intake and energy expenditure, and therefore represents a logical target for interventions. Anticipatory guidance by pediatricians may offer an effective mechanism by which to change parental attitudes and practices regarding television viewing. A similar process is used to emphasize the potential influence of school-based interventions directed at changes in food choices and sedentary behavior.

Dieting and smoking initiation in early adolescent girls and boys: a prospective study.

OBJECTIVES: This analysis tested the relation between dieting frequency and risk of smoking initiation in a longitudinal sample of adolescents. METHODS: From 1995 to 1997, 1295 middle school girls and boys participated in a nutrition and physical activity intervention study. The prospective association between dieting frequency at baseline and smoking initiation 2 years later was tested. RESULTS: Compared with girls who reported no dieting at baseline, girls who dieted up to once per week had 2 times the adjusted odds of becoming smokers (odds ratio = 2.0; 95% confidence interval = 1.1, 3.5), and girls who dieted more often had 4 times the adjusted odds of becoming smokers (odds ratio = 3.9; 95% confidence interval = 1.5, 10.4). CONCLUSIONS: Dieting among girls may exacerbate risk of initiating smoking, with increasing risk with greater dieting frequency.

Household television access: associations with screen time, reading, and homework among youth.

OBJECTIVE: We examined how household factors that mediate television access are associated with screen time (television, videos, movies, and computer and video games), reading, and homework. METHODS: We conducted a self-report survey among 1197 sixth and seventh graders in 10 middle schools in 4 Boston-area communities in 1995. To assess independent associations, SUDAAN linear regressions were calculated to control for respondent characteristics and household access and to account for clustered sampling in the school-based design. RESULTS: Total viewing (television, videos, movies, and computer and video games) averaged 3.35 plus minus 2.2 hours per day. In multivariate regressions, independent direct associations with total viewing were observed for the following categories: youth has a television in the bedroom: 0.64 hours per day (P <.001), never/seldom has family dinners: 0.55 hours (P <.01); no parental limits on television time: 0.48 hours (P <.01); and each additional television outside the youth's bedroom, 0.12 hours (P <.05). Similar results held when television/video/movie use was examined separately from computer/video game use. Youth reported an average of 1.6 plus minus 1.1 hours of reading and homework per day. Parental limits on television time were associated with 0.21 hours more reading per day (P <.01), whereas a television in the bedroom was associated with 0.18 hours less (P <.01). CONCLUSIONS: Reducing intrahousehold television access may enhance clinical, school, and community strategies to reduce youth television viewing and other screen time.

Effect of combination therapy including protease inhibitors on mortality among children and adolescents infected with HIV-1.

BACKGROUND: Combination therapy including protease inhibitors has been shown to be effective in treating adults infected with human immunodeficiency virus type 1 (HIV-1), but there are only limited data regarding the treatment of children and adolescents. METHODS: A cohort of 1028 HIV-1-infected children and adolescents, from birth through 20 years of age, who were enrolled in research clinics in the United States before 1996 was followed prospectively through 1999. We used proportional-hazards regression models to estimate the effect on mortality of combination therapy including protease inhibitors. RESULTS: Seven percent of the subjects were receiving combination therapy including protease inhibitors in 1996; by 1999, 73 percent were receiving such therapy. In univariate analyses, a higher base-line percentage of lymphocytes that were CD4-positive, a higher weight for age, a higher height for age, black race, Hispanic ethnic background, younger age, and perinatally acquired infection were associated with a longer median time to the initiation of this type of therapy (P<0.001). After adjustment for covariates, the differences among racial and ethnic groups in the time to initiation were not statistically significant. Mortality declined from 5.3 percent in 1996 to 2.1 percent in 1997, 0.9 percent in 1998, and 0.7 percent in 1999 (P for trend <0.001). There were reductions in mortality in all subgroups defined according to age, sex, percentage of CD4+ lymphocytes, educational level of the parent or guardian, and race or ethnic background. In adjusted analyses, the initiation of combination therapy including protease inhibitors was independently associated with reduced mortality (hazard ratio for death, 0.33; 95 percent confidence interval, 0.19 to 0.58; P<0.001). CONCLUSIONS: The use of combination therapy including protease inhibitors has markedly reduced mortality among children and adolescents infected with HIV-1.

[Validity and reproducibility of a questionnaire on physical activity and non-activity for school children in Mexico City]. / Validez y reproducibilidad de un cuestionario de actividad e inactividad física para escolares de la ciudad de México.

OBJECTIVE: To assess the validity and reproducibility of a self-reported questionnaire on physical activity and inactivity, developed for children aged 10-14 in Mexico City. MATERIAL AND METHODS: Between May and December 1996, a self-reported physical activity and inactivity questionnaire was developed and applied twice to a sample of 114 students aged 10 to 14, from a low and middle income population of Mexico City. The children's mothers completed the same questionnaire, and two 24-hour recalls of physical activity were used for comparison. Statistical analysis consisted of central tendency and dispersion measures and Pearson's correlation coefficient. RESULTS: Correlations between hours per day spent in physical activity and inactivity from the children's questionnaire and the 24-hour recall data, were 0.03 for moderate activity, 0.15 for vigorous activity, and 0.51 (p = 0.001) for watching television, adjusted by age, gender, town, and illness prior to the administration of the questionnaire. Compared to the 24-hour recall data, the questionnaire overestimated the time spent watching television, reading or participating in vigorous activity, and underestimated the time engaged in moderate activity. Statistically significant (p < 0.05) six-month reproducibility values were observed for watching television (r = 0.53), sleeping (r = 0.40), moderate (r = 0.38), and vigorous activity (r = 0.55). CONCLUSIONS: Among children of Mexico City aged 10-14, the questionnaire showed acceptable validity in estimating the time watching television, and acceptable reproducibility of the time watching television, vigorous and moderate activity.

Effects of negative life events on immune suppression in children and youth infected with human immunodeficiency virus type 1.

OBJECTIVES: To evaluate the association of negative stressful life events experienced over 12 months and the risk of moderate to severe immune suppression among children and youth infected with human immunodeficiency virus type 1 (HIV-1). METHODS: Longitudinal study of 618 HIV-1-infected children, baseline ages 1 to 20 years (mean age: 6.4 years), who completed 52 weeks of participation in the Pediatric Late Outcomes Study (Pediatric AIDS Clinical Trials Group Protocol 219). Severity of immune suppression was indicated by the Centers for Disease Control and Prevention Pediatric HIV Disease Classification System, based on CD4 percentages. The total number of negative life events-categorized as none, 1, or >1 life event reported as having occurred in the previous 12 months (previous 6 months for children <3 years of age)-was the predictor variable. Multiple logistic regressions were estimated to assess the relationship of negative life events and immune suppression at outcome, controlling for baseline measures of immune suppression, continuous CD4%, negative life events, age, race/ethnicity, gender, primary caretaker, education level of caretaker, and acquired immunodeficiency syndrome status. RESULTS: At week 52, 379 subjects (61% of total study population) had moderate to severe immune suppression. Of 275 children with normal immune function at baseline, 68 (24.7%) subsequently developed moderate to severe suppression levels by week 52 of follow-up. Of 343 children with immune suppression at baseline, 32 (9.2%) had recovered to normal CD4% levels by week 52. More than 1 negative life event was associated with an increased risk (prevalence) of immune suppression (odds ratio [OR]: 2.76; 95% confidence interval [CI]: 1.44,5.31), controlling for baseline CD4%, total life events, and other covariates. Children without immune suppression at baseline who experienced >1 negative life event had an increased incidence of immune suppression (OR: 2.93; 95% CI: 1.34,6.39), controlling for baseline covariates. CONCLUSIONS: Results indicate that negative stressful life events increase the risk of children with HIV-1 infection having impaired immune function. Further research is needed to identify potential mechanisms of the relationship between stressful life events and impaired immune function. These mechanisms include psychoneuroendocrinologic response and difficulties in adherence to therapy after exposure of a child to major negative life events.

Assessment of non-response bias in a probability household survey of male same-gender sexual behavior.

OBJECTIVE: To assess non-participation bias in a survey of male sexual behavior. MATERIAL AND METHODS: A household survey was carried out in 1992-1993 using a probability sampling frame in Mexico City. Demographic variables were available for all eligible men. The extent of non-participation bias was estimated using a version of the Heckman method, which utilizes two equations, one to predict participation and the other to predict reports of same-gender sexual behavior. RESULTS: A total of 8,068 of the 13,713 eligible men completed a face-to-face questionnaire (response rate 59%); 173 men (2.1%) reported bisexual behavior in their lifetime, and 37 (0.4%) reported only male partners. Survey participation was predicted using demographic variables: 67% of the observations were correctly predicted by a probit regression model: 82% of participants and 53% of non-participants (pseudo-r2 = 0.13). Same-gender sexual behavior was predicted by variables indicating attachment to gay/bisexual social networks, history of sexually transmitted diseases, positive attitudes towards gay and bisexual males, and lack of support from male relatives. Ninety-seven per cent of the cases was correctly predicted by the probit model (pseudo-r2 = 0.14). The correlation between these two equations was not statistically significant. CONCLUSIONS: These results indicate that prevalence estimates of same-gender sexual behavior among Mexico City men were not biased by selective survey participation. Careful selection and training of household interviewers may have assisted in minimizing potential bias.

Impact of expanding SSI on Medicaid expenditures of disabled children.

Supplemental Security Income (SSI) expansions for disabled children in the early 1990s provoked criticism that eligibility criteria were too lax and motivated the subsequent retraction of benefits for many children. However, little evidence exists on whether the clinical needs of SSI children declined during this period. The authors used Medicaid data to examine changes in average expenditures between 1989 and 1992, using an Aid to Families with Dependent Children (AFDC) comparison group to control for confounding time trends (e.g., in access). Results showed declines in average expenditures in Georgia and Tennessee but increases in California and Michigan, which are thought to have started with more liberal eligibility policies.

Reproducibility and validity of a food frequency questionnaire among fourth to seventh grade inner-city school children: implications of age and day-to-day variation in dietary intake.

OBJECTIVE: To assess the reproducibility and validity of a semiquantitative food frequency questionnaire (FFQ) to classify children and adolescents in terms of daily servings of fruits and vegetables and intake of calories, protein, fat, carbohydrate, dietary fibre, vitamin C, phosphorous, calcium and iron. DESIGN: FFQs were collected in the autumn of 1993 and 1994. Four 24-hour diet recalls were collected during the same 1-year period and their mean was compared to the FFQ diet estimates. SETTING: Low income, inner-city state schools. SUBJECTS: A sample of 109 inner-city fourth to seventh grade students. RESULTS: The 1-year reproducibility of the FFQ, assessed with Spearman correlations, was lower among the fourth and fifth (range: r=-0.26 to 0.40) than the sixth and seventh grade students (range: r=0.18-0.47). After adjusting for day-to-day variation in dietary intake, for most nutrients and foods the correlations between the FFQ and the 24-hour recalls remained greater among the junior high school students (fourth to fifth grade range: r=0.0-0.42; sixth to seventh grade range: r=0.07-0.76). CONCLUSIONS: Inner-city sixth and seventh grade students demonstrated the ability to provide valid estimates of intake of calories, carbohydrate, calcium, phosphorous, iron and vitamin C over the past year. However, children in the fourth and fifth grades experienced some difficulty in completing the FFQ. Our results suggest that, before using this instrument with fourth and fifth grade children, investigators should assess whether study participants can think abstractly and are familiar with the concept of 'average intake'.

Association of obesity with physical activity, television programs and other forms of video viewing among children in Mexico city.

OBJECTIVE: To assess the association of physical activity, television program viewing and other forms of video viewing with the prevalence of obesity among school children. DESIGN: Cross-sectional study. SUBJECTS: 712 children, 9-16 y old, from a low- and a middle-income town in the Mexico City area. MEASUREMENTS: Children completed a self administered questionnaire to assess time spent in physical activity and television viewing, and diet. Height weight and triceps skinfolds were measured. The outcome variable was obesity, and the covariates were hours of television programs and other video viewing, physical activity, energy intake, percentage of energy from fat, town of location of school, age, gender and perception of mother's weight status. RESULTS: Among 461 children with complete information, 24% were classified as obese. Children reported an average of 4.1 +/- 2.2 h/d watching television (2.4 +/- 1.5 h/d for TV programs and 1.7 +/- 1.5 h/d for video cassette recorder (VCR) or videogames), and 1.8 +/- 1.3 h/d in moderate and vigorous physical activities. Odds ratios (OR) of obesity were 12% higher for each hour of television program viewing per day (OR = 1.12, 95% confidence interval (CI) 1.02,-1.22), and 10% lower for each hour of moderate/vigorous physical activity per day (OR = 0.90, 95% CI 0.83-0.98), controlling for age, gender, town and perception of mother's weight status. Children in the middle-income town had higher adjusted odds of obesity (OR = 2.58, 95% CI 1.47-4.54). CONCLUSION: Physical activity and television viewing, but not VCR/videogames use, were related to obesity prevalence in Mexican children 9-16 y old.

Impact of a school-based interdisciplinary intervention on diet and physical activity among urban primary school children: eat well and keep moving.

OBJECTIVE: To evaluate the impact of a school-based interdisciplinary health behavior intervention on diet and physical activity among children in grades 4 and 5. DESIGN: A quasiexperimental field trial with 6 intervention and 8 matched control schools. Outcomes were assessed longitudinally using preintervention (fall 1995) and follow-up (spring 1997) student survey food frequency and activity measures and follow-up 24-hour recall measures of diet and activity. Change was also assessed using yearly repeated cross-sectional surveys of all grade 5 students from 1995 through 1997. PARTICIPANTS: Longitudinal data were collected from 479 students initially in grade 4 in Baltimore, Md, public schools; 91% were African American. Repeated 24-hour recall measures in 1997 were collected for a random subsample of 336 students. Cross-sectional survey data were collected from all grade 5 students in 1995,1996, and 1997 (n = 2103). INTERVENTION: The Eat Well and Keep Moving Program was taught by classroom teachers over 2 years in math, science, language arts, and social studies classes. Materials provided links to school food services and families and provided training and wellness programs for teachers and other staff members. Intervention materials focused on decreasing consumption of foods high in total and saturated fat and increasing fruit and vegetable intake, as well as reducing television viewing and increasing physical activity. MAIN OUTCOME MEASURES: Dietary intake and physical activity measured via repeated 24-hour recall were primary end points, with additional food frequency and activity measures. RESULTS: The 24-hour recall measures indicated that, after controlling for baseline covariates, the percentages of total energy from fat and saturated fat were reduced among students in intervention compared with control schools (-1.4%; 95% confidence interval [CI], -2.8 to -0.04; P = .04 and -0.60%; 95% CI, -1.2 to -0.01; P = .05). There was an increase in fruit and vegetable intake (0.36 servings/4184 kJ; 95% CI, 0.10-0.62; P=.01), in vitamin C intake (8.8 mg/4184 kJ; 95% CI, 2.0-16; P=.01), and in fiber consumption (0.7 g/4184 kJ; 95% CI, 0.0-1.4; P=.05). Television viewing was marginally reduced (-0.55 h/d; 95% CI, -1.04 to 0.04; P=.06). Analysis of longitudinal and repeated cross-sectional food frequency data indicated similar significant decreases in the percentages of total energy from fat and saturated fat. CONCLUSION: Evaluation of the Eat Well and Keep Moving Program indicates effectiveness in improving dietary intake of students and reducing television viewing.

Reducing obesity via a school-based interdisciplinary intervention among youth: Planet Health.

OBJECTIVE: To evaluate the impact of a school-based health behavior intervention known as Planet Health on obesity among boys and girls in grades 6 to 8. DESIGN: Randomized, controlled field trial with 5 intervention and 5 control schools. Outcomes were assessed using preintervention (fall 1995) and follow-up measures (spring 1997), including prevalence, incidence, and remission of obesity. PARTICIPANTS: A group of 1295 ethnically diverse grade 6 and 7 students from public schools in 4 Massachusetts communities. INTERVENTION: Students participated in a school-based interdisciplinary intervention over 2 school years. Planet Health sessions were included within existing curricula using classroom teachers in 4 major subjects and physical education. Sessions focused on decreasing television viewing, decreasing consumption of high-fat foods, increasing fruit and vegetable intake, and increasing moderate and vigorous physical activity. MAIN OUTCOME MEASURES: Obesity was defined as a composite indicator based on both a body mass index and a triceps skinfold value greater than or equal to age- and sex-specific 85th percentiles. Because schools were randomized, rather than students, the generalized estimating equation method was used to adjust for individual-level covariates under cluster randomization. RESULTS: The prevalence of obesity among girls in intervention schools was reduced compared with controls, controlling for baseline obesity (odds ratio, 0.47; 95% confidence interval, 0.24-0.93; P = .03), with no differences found among boys. There was greater remission of obesity among intervention girls vs. control girls (odds ratio, 2.16; 95% confidence interval, 1.07-4.35; P = .04). The intervention reduced television hours among both girls and boys, and increased fruit and vegetable consumption and resulted in a smaller increment in total energy intake among girls. Reductions in television viewing predicted obesity change and mediated the intervention effect. Among girls, each hour of reduction in television viewing predicted reduced obesity prevalence (odds ratio, 0.85; 95% confidence interval, 0.75-0.97; P = .02). CONCLUSION: Planet Health decreased obesity among female students, indicating a promising school-based approach to reducing obesity among youth.