|AAP||American Academy of Pediatrics|
|ACHI||Arkansas Center for Health Improvement|
|Add Health||National Longitudinal Survey of Adolescent to Adult Health|
|AHRQ||Agency for Healthcare Research and Quality|
|APT||Assessing Prevalence and Trends (Framework)|
|B-24/P||Dietary Guidance Development Project for Birth to 24 Months and Pregnancy|
|BIA||bioelectrical impedance analysis|
|BIV||biologically implausible value|
|BMI||body mass index|
|BRFSS||Behavioral Risk Factor Surveillance System|
|CARDIAC||Coronary Artery Risk Detection in Appalachian Communities (Study)|
|CAYPOS||Child and Youth Prevalence of Overweight Survey|
|CDC||Centers for Disease Control and Prevention|
|CENTURY||Collecting Electronic Nutrition Trajectory Data Using Records of Youth (Study)|
|CHAMACOS||Center for the Health Assessment of Mothers and Children of Salinas|
|CHIS||California Health Interview Survey|
|CHNA||community health needs assessment|
|DXA||dual-energy X-ray absorptiometry|
|EAT||Eating Among Teens (Study)|
|ECHO||Environmental Influences on Child Health Outcomes|
|ECLS-B||Early Childhood Longitudinal Survey-Birth Cohort|
|EHR||electronic health record|
|FERPA||Family Educational Rights and Privacy Act|
|FNS||Food and Nutrition Service (USDA)|
|FPL||federal poverty level|
|GOe||Global Observatory for eHealth|
|GUTS||Growing Up Today Study|
|HEALTH-KIDS||Healthy Eating and Active Lifestyles from school To Home for KIDS|
|HEDIS||Healthcare Effectiveness Data and Information Set|
|HFZ||Healthy Fitness Zone®1|
|HIPAA||Health Insurance Portability and Accountability Act of 1996|
|HSR||health service region|
|i3C||International Childhood Cardiovascular Cohort (Consortium)|
|ICD||International Classification of Diseases|
|IOM||Institute of Medicine|
|IOTF||International Obesity Task Force|
|IRB||Institutional Review Board|
|ITO||Indian Tribal Organization|
|KPSC||Kaiser Permanente Southern California|
|MCIR||Michigan Care Improvement Registry|
|MEPS-HC||Medical Expenditure Panel Survey-Household Component|
|MGRS||Multicentre Growth Reference Study|
1Healthy Fitness Zone®is a registered trademark of The Cooper Institute.
|NCCOR||National Collaborative on Childhood Obesity Research|
|NCHS||National Center for Health Statistics|
|NCQA||National Committee for Quality Assurance|
|NHANES||National Health and Nutrition Examination Survey|
|NHES||National Health Examination Survey|
|NHIS||National Health Interview Survey|
|NHPI||Native Hawaiian and Pacific Islander|
|NICHD||National Institute of Child Health and Human Development|
|NI–HR||Needs Improvement–Health Risk|
|NLSY||National Longitudinal Survey of Youth|
|NSCH||National Survey of Children’s Health|
|NS-CSHCN||National Survey of Children with Special Health Care Needs|
|OMB||Office of Management and Budget|
|PC||WIC Participant and Program Characteristics|
|PedNSS||Pediatric Nutrition Surveillance System|
|PEDSnet PII||Pediatric EHR Data Sharing Network personally identifiable information|
|REGARDS||REasons for Geographic Differences in Stroke (Study)|
|RWJF||Robert Wood Johnson Foundation|
|SAE||small area estimation|
|SLAITS||State and Local Area Integrated Telephone Survey|
|SPAN||School Physical Activity and Nutrition (Survey)|
|USDA||U.S. Department of Agriculture|
|WHO||World Health Organization|
|WIC||Special Supplemental Nutrition Program for Women, Infants, and Children|
|YRBS||Youth Risk Behavior Survey|
|YRBSS||Youth Risk Behavior Surveillance System|
Fat accumulated around a person’s midsection; often assessed by measuring waist circumference or waist-to-hip ratio.
The simple difference between the estimated prevalence during time 2 and the estimated prevalence during time 1.
See Adipose tissue.
The point at which body mass index begins an increasing trajectory, after decreasing in early childhood due to a more rapid increase in height than weight. Adiposity rebound typically occurs between the ages of 4 and 7.
A technique used to assess body composition by determining body volume and density.
Approaches used for data preparation and statistical analysis.
Systematic deviation of results or inferences from the truth. This could result in the over- or under-estimation of the true value.
Bioelectrical impedance analysis (BIA)
A body composition assessment approach based on the principle that electrical currents travel at different speeds through lean body mass and water than through adipose tissue. In BIA, electrical currents are sent through the body and the resulting resistance (impedance) to the current is measured. The measure of impedance is used to calculate total body water, fat-free body mass, and fat mass.
Biologically implausible value (BIV)
An extreme value (high or low) falling outside of an expected range that may represent error in measuring an anthropometric factor or an error in data entry.
Describes how a child’s body mass index ranks compared to a reference population of the same sex and age. A BMI-for-age at the 95th percentile, for example, means that 95 percent of the reference population of the same sex and age had a BMI below that value, while 5 percent had a BMI above that value.
The number of standard deviations an individual’s BMI falls above or below the sex- and age-specific reference population’s mean. For example, a BMI z-score of +3 indicates a BMI that is 3 standard deviations higher than the mean BMI value in the reference population of the same sex and age.
The distribution of body fat, lean muscle tissue, water, and bone in an individual.
Body mass index (BMI)
An index commonly used to classify an individual’s weight status. BMI is calculated using the following equation:
BMI (kg/m2) = weight (kilograms) ÷ height (meters)2
Adults with a BMI of 30 kg/m2 or more are classified as having obesity. Children’s BMIs, in contrast, vary by sex and age. To be classified, a child’s BMI must be compared to a sex-specific, age-based distribution that has been determined in a reference population.
See Abdominal adiposity.
In this report, “change” describes the difference in obesity prevalence in a given population between two points in time. Change can be expressed as absolute or relative change (see Absolute change and Relative change).
An analytic epidemiologic study in which a defined population has been followed over time and the exposure of interest precedes the outcome variable. The main feature of a cohort study is the comparison of incidence rates in groups that differ in exposure levels.
Confidence interval (CI)
When a dataset does not include every individual in the population, the values that are produced are estimates of the true population parameter (e.g., prevalence of obesity). A CI can be constructed around the estimate, providing a range of values likely to include the true population parameter (e.g., actual prevalence of obesity in the population) and over unlimited repetitions of the study the CI will contain the true parameter with a frequency no less than its confidence level (often 95 percent is the stated level). Wider CIs indicate less precision around the estimate than narrower CIs.
An observational study that examines participants at one point in time. The temporal sequence of exposure and outcome (i.e., cause and effect) cannot be assured.
Significant changes to the demographic landscape of a population over time. Demographic shifts occurring in the U.S. population include increasing median age of the population, and changes in the racial and ethnic majority and minority groups.
Dual-energy X-ray absorptiometry (DXA)
A body composition assessment approach. Bone mineral density, fat mass, and lean body mass are determined based on the attenuation of two x-rays of differing energy levels as they pass through the body. Body composition estimates are derived from system-specific algorithms, which can differ between DXA machine manufacturers.
In this report, “end user” refers to an individual, group, or organization that uses one or multiple reports on obesity prevalence and trends to inform a decision.
In this report, “estimate (of obesity prevalence or trend)” describes a statistic about the proportion or number of individuals affected with obesity at one point in time (prevalence) or over time (trend). Estimates are known, believed, or suspected to incorporate some degree of error.
Estimate of obesity prevalence or trend
Distribution of growth among a reference population; the 2000 Centers for Disease Control and Prevention sex-specific BMI-for-age growth charts are an example of a growth reference. See Reference population.
Distribution of growth parameters among a reference population that exemplifies optimal growth. The World Health Organization has developed growth standards for children birth to age 5 years. See Reference population.
Systemic and preventable differences in the burden of disease and disability or opportunities to achieve optimal health between particular population groups due to economic, racial, cultural, geographic, social factors, or other determinants.
An online population-based database to record and monitor all immunizations administered by health care providers; immunization registries are not required for all health care providers.
An experimental study designed to test a specific hypothesis in which one or multiple factors are modified to determine the factor’s effect(s) on outcomes of interest.
In this report, “investigators” describes anyone who designs studies or performs data collection, analyses, or reporting.
Lean body mass
Body mass not including adipose tissue.
An observational study that examines a selected population at multiple points over time. A cohort study is a longitudinal study. See Cohort study.
In this report, “methodology” describes elements related to study design and data collection.
Mobile health (mHealth)
The use of mobile devices and the development of applications for medical and public health purposes.
Disease or illness in a population. Morbidity is frequently measured as prevalence of a disease.
Deaths in a population.
A state of excess adiposity. For more information on how obesity is commonly assessed in population-based assessments, see Body mass index.
Sampling procedure used to increase the number of individuals from a specific subgroup included in a dataset. Population groups that represent a small portion of the overall target population can be intentionally oversampled in order to generate a reliable estimate of obesity prevalence or trend.
In this report, “population” refers to the total set of individuals about whom inferences are being made in a study. A sample is the subset of people included in the analysis.
In this report, “prevalence” describes the number of individuals in a sample or subgroup classified as having obesity in relation to the total sample or subgroup at a given point in time.
In this report, “proxy-report” refers to data provided by someone other than the child of interest. This may be a parent, guardian, or other adult who is knowledgeable about the child.
In this report, “published report” refers to a publication, peer-reviewed or otherwise, with original analysis that produces an estimate of obesity prevalence or trend.
The change in the estimated prevalence in percentage terms (i.e., the absolute change as a percentage of the estimated prevalence during time 1).
The extent to which results obtained through a specific measurement protocol or assessment technique can be replicated or reproduced.
Repeated cross-sectional study
A cross-sectional study conducted at multiple points in time. The sample of individuals is different at each assessment (as opposed to a longitudinal study, where the participants remain the same over time).
Report on prevalence or trends
In this report, describes a publication, peer-reviewed or otherwise, with original analysis that produces a value of magnitude and/or a directionality of the magnitude over time of the issue of obesity within a defined population group.
The process used for selection of individuals to be included in a dataset.
In this report, “school-based assessment” refers to any data collection effort conducted in the school setting (a single school or multiple schools), specifically those that collect height and weight data.
Any tool used to identify potential signs of illness or disease before symptoms are apparent. In the context of this report, BMI serves as a screening tool for excess adiposity.
Long-term trends, usually over 10 years or more.
In this report, “self-report” refers to information reported by individuals about themselves.
A further classification of obesity status. Adults with a BMI of 40 kg/m2 or greater are classified as having severe obesity. Children’s BMIs, in contrast, vary by sex and age, so a single BMI cut point cannot be used. Instead, a child’s BMI must be compared to an age-based distribution that has been assessed in a reference population.
Skinfold thickness is an assessment of body fat based on a measure of a double fold of the skin and subcutaneous fat at various selected sites on the body. Skinfold thickness measurement can be used in predictive equations to determine an individual’s percent body fat.
A measure used to quantify the amount of variation or dispersion in a dataset. The standard deviation is the square root of the variance.
An estimate of the standard deviation of the sampling distribution of a statistic, most commonly of the mean. See Standard deviation.
In this report, “statistical analysis” specifically refers to the analytic procedures that result in an estimate of obesity prevalence or trend.
See Statistical analysis.
Adipose tissue directly under the skin.
In this report, surveillance refers to the process of ongoing and systematic data collection, analysis, and interpretation, and subsequent disclosure of results.
The population group an estimate from the study population is intended to reflect.
Total body fat; does not describe the location and distribution of adipose tissue.
In this report, a trend is the change in prevalence of obesity in a given population over three or more points in time.
A body composition assessment calculated by measuring body weight (as taken on land), body weight underwater, and the amount of dis-
placed water when an individual is submerged in a water tank. The protocol for underwater weighing requires an individual to be fully submerged, to have blown out as much air from their lungs as possible, and to remain still while the measurement is being taken.
The extent to which an assessment measures what it is intended to measure. Or, the relative absence of bias or systematic error.
Fat surrounding body organs.
A measure of abdominal adiposity; standard protocol for measuring waist circumference varies.
Calculated by dividing waist circumference by height; often used in relation to obesity-related comorbidities.
Calculated by dividing waist circumference by hip circumference; often used in relation to obesity-related comorbidities.
With respect to obesity prevalence and trends estimates representative of a target population, assigning each participant a value (“weight”) corresponding to their probability of selection. Those having higher probabilities of selection (e.g., being from a group that was oversampled) would be assigned smaller weights.