Examining relationships between U.S. children's physical activity levels during recess, school days, and weekend days.

Objective: Physical activity opportunities, such as recess, in educational settings are vital yet only a handful of states have policies in place to ensure daily minimum recess allotment. We aim to investigate associations between physical activity during recess and other time periods to better understand the extent to which recess physical activity is related to physical activity throughout the week.

Methods: Children K-5th grade were from four schools in Little Rock, Arkansas.

Playing Alone: Recess Physical Activity and Social Interactions of Children with and Without Obesity and Severe Obesity.

This study aimed to compare recess physical activity, social behaviors, and social/school perceptions among children with obesity and severe obesity and those without obesity. Recess observations were done using the System of Observing Children's Activity and Relationships during Play. School climate surveys and anthropometric measurements were also completed.

Ambient Environment and the Epidemiology of Preterm Birth.

Preterm birth (PTB) is associated with substantial mortality and morbidity. We describe environmental factors that may influence PTB risks. We focus on exposures associated with an individual's ambient environment, such as air pollutants, water contaminants, extreme heat, and proximities to point sources (oil/gas development or waste sites) and greenspace.

Where the children play: Gender gaps in recess physical activity by age and playground area.

Objective: Recess contributes meaningfully to physical activity (PA), but recess time has declined. The study's purpose was to report PA by age, gender, and playground feature to inform potential playground configurations more conducive to PA during recess.

Methods: Using the System for Observing Play and Leisure Activity in the Youth, kindergarten through 5th grade recesses were observed on at least four days at four schools in Little Rock, Arkansas, United States during May 2023.

A search for factors associated with reduced carbohydrate intake and NTD risk in two population-based studies.

Background: Two population-based case-control studies have reported an increased risk of neural tube defect (NTD)-affected pregnancies among women with low carbohydrate diet in the periconceptional period. Given that only two studies have investigated this association, it is unclear to what degree the findings could be impacted by residual confounding. Here, we further interrogated both studies that observed this association with the objective to identify factors from a much larger number of factors that might explain the association.

Comparison of Trihalomethane exposure assessment metrics in epidemiologic analyses of reproductive and developmental outcomes.

Background: Researchers have developed exposure assessment metrics for disinfection by-products (DBPs) utilizing drinking water monitoring data and accounting for spatial and temporal variability, water consumption, and showering and bathing time with an expectation of decreasing exposure misclassification compared to the use of measured concentrations at public water supply (PWS) monitoring locations alone.

Objective: We used exposure data collected for a previous study of DBPs to evaluate how different sources of information impact trihalomethane (THM) exposure estimates.

Methods: We compared gestational exposure estimates to THMs based on water utility monitoring data alone, statistical imputation of daily concentrations to incorporate temporal variability, and personal water consumption and use (bathing and showering).

Evaluation of the Little Rock Green Schoolyard initiative: a quasi-experimental study protocol.

Background: Evidence suggests that access to green schoolyards may facilitate vigorous play and lead to increased physical activity, which could lead to improved academic outcomes and reduce excess childhood weight gain. Greener schoolyards can also provide additional outdoor amenities that help the community at large. The Little Rock Green Schoolyard Initiative, a program aiming to promote outdoor learning and play in two of the city's community schools, provides a natural experiment to evaluate the role of such interventions.

Assessing associations between residential proximity to greenspace and birth defects in the National Birth Defects Prevention Study.

Background: Residential proximity to greenspace is associated with various health outcomes.

Objectives: We estimated associations between maternal residential proximity to greenspace (based on an index of vegetation) and selected structural birth defects, including effect modification by neighborhood-level factors.

Methods: Data were from the National Birth Defects Prevention Study (1997-2011) and included 19,065 infants with at least one eligible birth defect (cases) and 8925 without birth defects (controls) from eight Centers throughout the United States.

Greenspace, Air Pollution, Neighborhood Factors, and Preeclampsia in a Population-Based Case-Control Study in California.

To investigate preeclampsia etiologies, we examined relationships between greenspace, air pollution, and neighborhood factors. Data were from hospital records and geocoded residences of 77,406 women in San Joaquin Valley, California from 2000 to 2006. Preeclampsia was divided into mild, severe, or superimposed onto pre-existing hypertension.

Residential proximity to green space and preeclampsia in California.

Background: We investigated whether residing near more green space might reduce the risk of preeclampsia.

Methods: Participants were women who delivered a live, singleton birth between 1998 and 2011 in eight counties of the San Joaquin Valley in California. There were 7276 cases of preeclampsia divided into mild, severe, or superimposed on preexisting hypertension.

Periconceptional stressors and social support and risk for adverse birth outcomes.

Background: The prevalence of preterm birth and low birth weight has been increasing slightly in recent years. A few studies have suggested that psychosocial stress during pregnancy may increase risk for these adverse birth outcomes. To extend those observations, we analyzed various major life event stressors separately and cumulatively as potential risk factors for preterm birth and low birth weight using granular categories of each outcome in a large, population-based study.

Air Pollution, Maternal Hypertensive Disorders, and Preterm Birth.

Background: Air pollution has been associated with hypertension and preterm birth. We examined if prenatal exposure to air pollutants was associated with gestational hypertension and if its association with preterm birth was modified by maternal hypertension.

Methods: Data were from birth certificates and hospital discharge records of 252,205 women in San Joaquin Valley of California from 2000-2006.

Data-driven queries between medications and spontaneous preterm birth among 2.5 million pregnancies.

Background: Our goal was to develop an approach that can systematically identify potential associations between medication prescribed in pregnancy and spontaneous preterm birth (sPTB) by mining large administrative "claims" databases containing hundreds of medications. One such association that we illustrate emerged with antiviral medications used for herpes treatment.

Methods: IBM MarketScan® databases (2007-2016) were used.

A machine learning approach to investigate potential risk factors for gastroschisis in California.

Background: To generate new leads about risk factors for gastroschisis, a birth defect that has been increasing in prevalence over time, we performed an untargeted data mining statistical approach.

Methods: Using data exclusively from the California Center of the National Birth Defects Prevention Study, we compared 286 cases of gastroschisis and 1,263 non-malformed, live-born controls. All infants had delivery dates between October 1997 and December 2011 and were stratified by maternal age at birth (<20 and ≥ 20 years).

An application of data mining to identify potential risk factors for anophthalmia and microphthalmia.

Background: We examined a large number of variables to generate new hypotheses regarding a wider range of risk factors for anophthalmia/microphthalmia using data mining.

Methods: Data were from the National Birth Defects Prevention Study, a multicentre, case-control study from 10 centres in the United States. There were 134 cases of "isolated" and 87 "nonisolated" (with other major birth defects) of anophthalmia/microphthalmia and 11 052 nonmalformed controls with delivery dates October 1997-December 2011.

Epidemiology of anophthalmia and microphthalmia: Prevalence and patterns in Texas, 1999-2009.

Anophthalmia and microphthalmia are a set of rare, yet severe, birth defects considered to be part of a spectrum of developmental ocular malformations ranging from smaller than average to completely absent eyes. Despite their clinical significance, little is known about the etiologies of these conditions. The goal of this study was to expand our understanding of the epidemiology of anophthalmia and microphthalmia.

Racial differences in maternal and umbilical cord blood leukocyte telomere length and their correlations.

Purpose: Telomere length at birth sets the baseline for telomere shortening and may influence adult disease risk like cancer. Telomere length is heritable, but may also be a marker of exposures in utero, including those influencing racial differences in risk. We examined racial differences in telomere length in maternal and umbilical cord blood from male neonates, and maternal-neonate correlations to generate hypotheses.

Residential agricultural pesticide exposures and risks of preeclampsia.

We investigated risks of preeclampsia phenotypes from potential residential pesticide exposures, including 543 individual chemicals and 69 physicochemical groupings that were applied in the San Joaquin Valley of California during the study period, 1998-2011. The study population was derived from birth certificate data linked with Office of Statewide Health Planning and Development maternal and infant hospital discharge data. The following numbers of women with preeclampsia phenotypes were identified: 1045 with superimposed (pre-existing hypertension with preeclampsia) preeclampsia (265 with gestational weeks 20-31 and 780 with gestational weeks 32-36); 3471 with severe preeclampsia (824 with gestational weeks 20-31 and 2647 with gestational weeks 32-36); and 2780 with mild preeclampsia (207 with gestational weeks 20-31 and 2573 with gestational weeks 32-36).

Nutrient intake in women before conception and risks of anophthalmia and microphthalmia in their offspring.

Background: We previously explored associations between nutrients including folate and other macro and micronutrients and risks of anophthalmia or microphthalmia in the National Birth Defects Prevention Study. In the current study, we expand those previous results with larger sample sizes and conduct analyses with an additional diet quality index using more recent data.

Methods: The National Birth Defects Prevention Study is a population-based, multicenter case-control study of over 30 major birth defects, with estimated due dates from October 1997 to December 2011.

Occurrence of Selected Structural Birth Defects Among Women With Preeclampsia and Other Hypertensive Disorders.

To explore a potential association between preeclampsia and selected birth defects, we examined the prevalence of certain birth defects among women with hypertensive disorders including preeclampsia. We analyzed data from 2,499,536 singleton live births in California from 2007 to 2011, including maternal and infant demographics from birth certificates as well as clinical details from delivery hospitalization records. We examined defect groups that were recognizable at birth (e.

Influence of In Utero Maternal and Neonate Factors on Cord Blood Leukocyte Telomere Length: Clues to the Racial Disparity in Prostate Cancer?

. Modifiable factors in adulthood that explain the racial disparity in prostate cancer have not been identified. Because racial differences in utero that may account for this disparity are understudied, we investigated the association of maternal and neonate factors with cord blood telomere length, as a cumulative marker of cell proliferation and oxidative damage, by race.