Trial Information

Vanguard Phase of the National Children's Study

The National Children's Study (NCS) is a planned observational longitudinal Study that will
enroll and follow a nationally representative sample of approximately 100,000 children born
in the U.S to participating women from before birth through their 21st birthday. The goal of
the NCS is to provide information that will ultimately lead to improvements in the health,
development, and well-being of children. The primary aim of the NCS is to investigate the
separate and combined effects of environmental exposures (chemical, biological, physical,
and psychosocial) as well as gene-environment interactions on pregnancy outcomes, child
health and development, and precursors of adult disease. In-person contacts with the NCS
participants will include visits during pregnancy at the participant's home and in a
clinical setting, collection of biologic samples and examination of the infant at birth, and
periodic contacts with the family and child throughout infancy and childhood. Interim phone
interviews between the in-person contacts also will occur. The NCS consists of the NCS
Vanguard Study with any sub-studies and the NCS Main Study with any sub-studies. The
Vanguard Study is the precursor to the Main Study.

The National Children's Study Vanguard Study is designed and implemented to determine the
feasibility, acceptability and cost of the elements that will form the Main Study. The
Vanguard Study is currently enrolling participants at seven Vanguard Centers and will have a
planned duration of 21 years following completion of enrollment and will precede the Main
Study on an ongoing basis to pilot all aspects of the Main Study. The specific objectives of
the Vanguard Study are:

1. Evaluation of recruitment, enrollment and retention strategies

2. Evaluation of Study logistics and operations including sites and mechanisms of data
acquisition, collection, transport and storage of environmental and biological samples
and design and performance of information systems

3. Evaluation of Study visit assessments for feasibility, reliability, reproducibility,
cost, value, redundancy with other assessments, stability and acceptability

Study visit assessments are the tests, environmental sample collections, biospecimens,
questionnaires and other forms of data acquisition that are scheduled at the study visits.

The evaluation of the Vanguard Study will be based on a series of targeted and specific
statistical techniques and tests selected for each evaluation. There will not be a single
hypothesis to test. Instead multiple performance measures will be used to inform the scope,
design, visit structure and schedule, mechanisms and procedures and analysis plan for the
Main Study.