Skip Navigation Links
Centers for Disease Control and Prevention


 CDC Home Search A-Z Index
Pediatric and Pregnancy Nutrition Surveillance System
Site Map Topic Index Glossary Bibliography Help
Illustration of a mother and children
Home
Pediatric Data Tables
Pregnancy Data Tables
Publications
What Is PedNSS/PNSS?
 What Is PedNSS?
 What is PNSS?
 PedNSS Health Indicators
 PNSS Health Indicators
How To...
 Read A Data Table
 Review Data Quality
 Interpret Data
 Disseminate Data
Additional Tools

What Is PedNSS/PNSS?
PedNSS Health Indicators

Data on specific health indicators are collected for infants and children who go to public health clinics for routine care, nutrition education, and supplemental food. Anemia, breastfeeding status, low and high birthweight, short stature, underweight, overweight, obesity, TV/video viewing, and household smoking are key indicators of nutritional status collected by the PedNSS. In the United States, weight and height are routinely measured to assess the nutritional status of children, and anemia is routinely assessed in children as an indicator of iron deficiency, the most common micronutrient deficiency. The definition of each indicator and the rationale for collecting the indicator are described below:

Birthweight
Low Birthweight
High Birthweight
Growth
Short Stature
Underweight
Overweight
Obese
Anemia
Low Hemoglobin/Hematocrit
Breastfeeding
Breastfeeding Initiation
Breastfeeding Duration
Exclusive Breastfeeding
Health Risk Behaviors
TV/Video Viewing
Smoking in the Household


Birthweight

  • Low birthweight (<2500 grams or <5.5 pounds) is the single most important factor affecting neonatal mortality and is a determinant of post-neonatal mortality (NAS, 1985). Infants weighing less than 2500 grams are almost 40 times more likely to die during their first four weeks of life than are infants of normal birthweight (Paneth, 1995). Although the infant mortality rate in the United States declined from 26 per 1000 live births in 1960 to 7 per 1000 live births in 1999, the nation ranks behind most industrialized countries for this health indicator. Low birthweight infants who survive are at increased risk for health problems ranging from neurodevelopmental handicaps to lower respiratory tract conditions (Paneth, 1995).
  • High birthweight (HBW) is defined as a birthweight of >4000 grams. This reflects the WIC Nutrition Risk Criteria (IOM, 1996) which is based on a generally accepted intrauterine growth reference > the 90th percentile weight for gestational age at birth (ACOG Technical Bulletin, 1991). High birthweight usually occurs in full-term or post-term infants but can occur in preterm infants. HBW puts infants at increased risk for birth injuries such as shoulder dystocia and infant mortality rates are higher among full-term infants who weigh more than 4000 grams than infants weighing between 3000 and 4000 grams.

Review the definition of Birthweight and its prevalence calculation.

back to top


Growth Indicators

  • Short stature is defined as a length or stature < 5th percentile on the CDC age- and gender-specific length or stature reference (CDC, 2000). Length/stature-for-age describes linear growth relative to age. Short stature, also referred to as low-length/height-for age or stunting, is used as an indicator of chronic malnutrition and it reflects the long-term health and nutritional history of a child. The child may be short due to poor nutrition and repeated infections. In some children short stature may be related to factors such as lower birthweight or short parental stature. The WIC Nutrition Risk Criteria (IOM, 1996) defines short stature as < 10th percentile in accordance with the preventive emphasis of the program.
  • Underweight is defined as weight-for-length < 5th percentile based on the CDC gender-specific weight-for-length reference for children less than 2 years of age and Body Mass Index (BMI )-for-age < 5th percentile for children 2 to 20 years of age based on the CDC gender-specific BMI-for-age reference (CDC, 2000). BMI is weight in kilograms divided by height in meters squared (kg/m2). Underweight, also referred to as thinness or wasting, is used as an indicator of acute malnutrition and it reflects recent starvation, persistent diarrhea, or both. The WIC Nutrition Risk Criteria (IOM, 1996) defines underweight as <10th percentile weight-for-length or BMI-for-age in accordance with the preventive emphasis of the program.
  • Obesity is defined as weight-for-length >95th percentile based on the CDC gender-specific weight-for-length reference for children less than 2 years of age and Body Mass Index (BMI )-for-age >95th percentile for children 2 to 20 years of age based on the CDC gender-specific BMI-for-age reference (CDC, 2000). BMI-for-age is not recommended for use in the United States before 2 years of age to assess growth. High BMI values at young ages have a weak association with adolescent or adult obesity (Whitaker et al., 1997; Guo et al., 1994). Obesity may indicate excess energy intake, low energy expenditure or both. The contribution of these factors to obesity has not been determined. Health problems associated with childhood obesity among children over the age of 2 include high blood pressure, high cholesterol, glucose intolerance, orthopedic disorders, and psychosocial disorders. In addition, longitudinal studies show that obesity in children over the age of 2 years is associated with overweight and obesity in adulthood.
  • Overweight: Expert committees have recommended a two-level screening for overweight among children 2 years and older. The recommendations are to use BMI-for-age at or above the 95th percentile to define obesity and between the 85th and 95th percentile to overweight (Himes and Dietz, 1994; Barlow and Dietz; 1998; Bellizzi and Dietz, 1999; Barlow 2007). Use of the 95th percentile identifies children with a significant likelihood of persistence of obesity into adulthood (Whitaker et al., 1997; Guo et al., 1994). In addition, using the 95th percentile cutoff point few children are incorrectly considered obese but many obese children are missed. Classifying children as overweight between the 85th to the 95th identifies overweight children that may have been missed by the 95th percentile cutoff point.

[Read More : interactive training modules that describe the CDC Growth Charts and commonly used anthropometric indices and evaluation criteria used to assess growth.]

Review the definition of Growth Indicators and its prevalence calculation.

back to top


Anemia

  • Anemia, a low hemoglobin (Hb) concentration or low hematocrit (Hct) level, is defined by age- and gender-specific cutoff values based on the 5th percentile from the third National Health and Nutrition Examination Survey for a healthy population (CDC, 1998). Children aged 1 to 2 years are considered anemic if their Hb concentration is less than 11.0 g/dL or Hct level is less than 33.0%; children aged 2 to 5 years are considered anemic if their Hb concentration is less than 11.1 g/dL or their Hct level is less than 33.3% (CDC, 1998). Because persons residing at higher altitudes have higher hemoglobin and hematocrit values, these values are automatically adjusted for altitude. Anemia is often used as an indicator of iron deficiency, the most common nutritional deficiency in the world (DeMaeyer, 1989). Iron deficiency is associated with developmental delays and behavioral disturbances in children (Pollitt, 1993; Idjradinata and Pollitt, 1993; Lozoff et al., 1991). Anemia associated with iron deficiency represents the final stage of iron deficiency when the production of hemoglobin (and other iron-containing functional compounds) falls below normal levels due to insufficient iron (Baynes, 1994).

[Read More for anemia cutoff values and recommendations to prevent and control iron deficiency in the United States]

Review the definition of Anemia and its prevalence calculation.

back to top


Breastfeeding

  • Breastfeeding Initiation is determined by Ever Breastfed while Breastfeeding Duration is determined by Breastfed at least 6 Months and Breastfed at least 12 Months: These breastfeeding practices were chosen in order to track three of the Healthy People 2010 objectives (USHHS, 2000). Breastfeeding continuation through the age of 18 months is also reported at weekly and monthly intervals. The nutritional, immunologic, allergenic, economic, and psychological advantages of breast feeding are well recognized. Breastfeeding is nutritionally superior to any alternative infant feeding method and provides immunity to many viral and bacterial diseases; enhances infants immunologic defenses; prevents or reduces risk of respiratory and diarrheal diseases; promotes correct development of jaws, teeth, and speech patterns; decreases tendency toward childhood obesity; and facilitates maternal-infant attachment (Jacobi and Levin, 1993; AAP, 1997).
  • Exclusive Breastfeeding is determined using responses from the Introduction to Supplementary Feeding data item. This data item indicates the age of the child when he or she was first fed something other than breastmilk and denotes the level of exclusive breastfeeding in the PedNSS population. Exclusive breastfeeding is defined as an infant's consumption of human milk with no supplementation of any type (including infant formula, cow's milk, juice, sugar water, baby food and anything else, even water) except for vitamins, minerals, and medications. This definition is consistent with that of the American Academy of Pediatrics Policy Statement on Breastfeeding and the Use of Human Milk (AAP 2005), and the World Health Organization (WHO 2004).

Review the definition of Breastfeeding and its prevalence calculation.

back to top


Health Risk Behaviors

  • TV/Video Viewing: Television viewing has been shown to increase overweight in children by displacing physical activity and increasing caloric intake (Robinson, 1999). This indicator is defined as the number of hours per day a child over the age of 2 spends sitting and watching television or videotapes on a typical day. This indicator is used to assess the amount of time children aged 2 and older spend viewing television and videotapes, and can be used to monitor the national health objective to increase the proportion of children who view TV 2 or fewer hours per day. The American Academy of Pediatrics recommends that parents be encouraged to limit their children's TV viewing to no more than 1 to 2 hours per day (AAP, 2001). Viewing more than 5 hours per day has been associated with increased incidence of overweight among older children compared with those watching 0–2 hours (Gortmaker et al, 1996).
  • Smoking in the Household: This indicator is defined as anyone in the household who currently smokes at the time of the child's visit. Secondary or passive smoke is a risk factor associated with poor growth in young children. Children exposed to environmental tobacco smoke have higher rates of lower respiratory illness during their first year of life, higher rates of middle ear effusion, and higher rates of sudden infant death syndrome. Additionally, children with asthma whose parents smoke have more severe symptoms and more frequent asthma episodes (AAP, 1997). The national health objectives call for a reduction in the proportion of children who are regularly exposed to tobacco smoke at home.

Review the definition of TV Viewing and its prevalence calculation.
Review the definition of Smoking in Household and its prevalence calculation.

back to top

Page last reviewed: October 29, 2009
Page last updated: October 29, 2009
Content Source: Division of Nutrition, Physical Activity and Obesity, National Center for Chronic Disease Prevention and Health Promotion

 

 



Policies and Regulations | Accessibility

CDC Home | Search | A-Z Index

United States Department of Health and Human Services
Centers for Disease Control and Prevention
National Center for Chronic Disease Prevention and Health Promotion
Division of Nutrition and Physical Activity