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Pediatric Data Tables
Pregnancy Data Tables
What Is PedNSS/PNSS?
What Is PedNSS?
Why was PedNSS created?
Who participates in PedNSS?
 What data are collected and analyzed?
How is PedNSS data used?
 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? - What is PedNSS?
What data are collected and analyzed?

Data Items

Data Items Collected
Demographic Clinic, county, date of birth, date of visit, race/ethnicity, sex, zip code , household income, migrant status, and source of data
Anthropometry birthweight, length/height, and weight
Anemia hemoglobin and hematocrit
Infant feeding practices breastfeeding initiation, duration, and exlusivity
Health Risk Behaviors TV/Video viewing, smokin gin the household

  • Demographic data collected by PedNSS include  race or ethnicity, sex, migrant status, household income (where indicated), and zip code.
  • Data collected to assess nutritional status include weight, length/height, and hemoglobin or hematocrit measurements. Weight, stature, and length are commonly used to assess the size and growth of children.
  • Data on birthweight and breastfeeding status are collected on children from birth to two years of age.
  • Health risk behavior data includes tv/video viewing and household smoking.


When any of these measures are combined with age, the result is an anthropometric index (e.g. weight-for-age). Body Mass Index (BMI) is an anthropometric index of weight and height that is defined as body weight in kilograms divided by height in meters squared (wt/ht2). BMI is the commonly accepted index for classifying adiposity in adults and it is recommended for use with children and adolescents over 2 years of age. BMI-for-age is used in place of weight-for-stature to identify children who are underweight, overweight, and obese. Anthropometric indices defined by age-and gender- specific percentile cutoff values using the CDC 2000 growth charts are used to assess the nutritional status of children and identify those that are of short stature, underweight, overweight and obese.

Anthropometric Indices and Nutritional Status Indicators
Anthropometric Index Percentile Cut Off Value Nutritional Status Indicators
Children Birth to 20 years of age
< 5th Percentile
Short stature
Children Birth to 2 years of age
> 95th Percentile
< 5th Percentile
Children 2 to 20 years of age
> 95th Percentile
> 85th and < 95th
< 5th Percentile


 Anemia, a low hemoglobin concentration or low hematocrit level, is defined by age-and gender specific cutoff values on the 5th percentile from the third National Health and Nutrition Examination Survey for a healthy population (CDC, 1998) [link to MMWR for values]. Anemia is routinely assessed in children as an indicator of iron deficiency, the most common micronutrient deficiency.

A description and rationale for collecting each health indicator is discussed in the section on PedNSS Health Indicators.

Data Collection Procedures and Data Dissemination

Data is collected at the clinic level then aggregated at the state level and submitted to CDC for analysis.

PedNSS Data Flow Chart
Chart showing clinics feeding data to states; states feeding data to CDC; CDC feeding data to states; states feeding data to clinics.

When multiple visit records are submitted for a child during the reporting period, CDC creates a unique child record following specific selection criteria that may contain some data from all available records. The CDC then calculates the nutrition-related indices and sends each contributor agency a series of annual tables that summarize the nutritional status and infant feeding practices by age of child and race/ethnicity. The national PedNSS tables are included in the Pediatric Data Tables section.

How is the unique child record created?

PedNSS Data Quality

CDC evaluates the completeness and quality of the data submitted from contributors and provides them with a data quality report. The report details missing and miscoded data, Biologically Implausible Values (BIVs) as well as other data quality problems. In addition, data quality parameters have been developed for each data item based on a variety of statistical measures including expected data distributions, standard deviation, and z-scores. Contributor data must meet specific data quality and completeness criteria to be included in the national PedNSS report.

Limitations of the PedNSS Data

PedNSS is a public health surveillance system based on data routinely collected from several federally funded public health programs serving low-income children. Contributors voluntarily participate in PedNSS. Not all contributors for a specific public health program participate in PedNSS. For example, not all states, U.S. territories, and tribal agencies that provide WIC services participate in PedNSS. Therefore, the national PedNSS report is not representative of all WIC programs. Similarly, PedNSS is not representative of all low-income children or children in the general population. It is representative of the population served by the public health program submitting the surveillance data. It is essential data for use in planning, implementing, monitoring, and evaluating the nutritional status of children served by a specific public health program.

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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


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