The impact of each Study visit and each assessment on the
participants, Study personnel, and Study infrastructure.
Advisory Committee to the Director Working Group (ACDWG)
A working group of the chartered federal advisory committee
established to assist the Office of the Director, NIH, in the
making of major plans and policies, especially those related
to the allocation of NIH funds and resources.
Alternate Recruitment Strategy (ARS)
See Recruitment Strategy/Recruitment Schema below.
Physical measurements of body size, shape, and composition such as
height or weight, waist circumference, skinfold thickness, etc.
A sample of biological material taken from the human body, such as blood,
plasma, urine, saliva, tissue, etc.
Centers for Disease Control and Prevention (CDC)
The CDC is a federal agency within the U.S. Department of Health and
Human Services. Its main goal is to protect public health and safety
through the control and prevention of disease, injury, and disability.
A test of one’s thinking capabilities. Cognitive function includes the
processes by which an individual perceives, registers, stores, retrieves,
and uses information.
Computer Assisted Personal Interview (CAPI)
An interviewing technique in which the study participant or the interviewer
uses a computer to administer questions and capture the answers.
Direct Outreach Recruitment (DO)
Also known as Two-tiered (or Hi/Lo) Recruitment Strategy, “Direct
Outreach” is a preferred term to describe this strategy that uses
marketing, direct mail, and other referral techniques to enroll a
broad-based population in larger geographic areas (SSUs) beyond
the predefined geographic segments. The approach is similar in
concept to the U.S. Census Short Form and Long Form, or the
Canadian Longitudinal Study on Aging. The Low Intensity National
Children’s Study provides participants with web-based, mail-in, or
telephone-based brief questionnaires administered at about every 6
months. From the pool of participants in the Low Intensity protocol,
those living in predefined geographic segments (TSUs) are invited
to participate in the High Intensity protocol, which follows the
Study visit schedule as that of the other recruitment strategies,
namely the EH and PB.
Enhanced Household-based Recruitment (EHBR)
During recruitment, this strategy utilized field workers who entered
predefined geographic segments and contacted individuals and families
at their residence. This strategy is similar to that used by the
initial seven Vanguard Centers, but was enhanced through application
of best practices from experience, targeted marketing campaigns,
enhancement of additional sources of referral into the Study(such as
health care providers, social clubs and organizations), and public
events, as well as streamlined enrollment procedures.
Refers to participants who consented to participate in the Study.
Environmental Protection Agency (EPA)
The United States Environmental Protection Agency (EPA) is an agency
of the U.S. federal government which was created for the purpose of
protecting human health and the environment.
Assessment of the technical performance of an aspect of the Study
visits logistics or infrastructure.
High Intensity/Low Intensity Dynamic Model (Hi/Lo)
Also known as Two-tiered Recruitment Strategy /Direct Outreach.
See Direct Outreach Recruitment (DO).
Information Management System (IMS)
An integrated system or set of systems consisting of hardware,
software, connectivity, and business rules that provides secure
administrative, computational, telecommunications, and data
collection and transmission functions.
Initial Vanguard Study (IVS)
The very first phase of the Vanguard Study, intended to serve
as a pilot to inform the planning of the National Children’s
Study Main Study. In the context of Vanguard Study data, IVS
refers to data collected in seven PSUs from January 2009 to
September 2010, when the IVS ended. The IVS recruitment was
based on area probability household sampling.
Institutional Review Board (IRB)
A committee established to review and approve research involving
human subjects, to assure that the research is conducted in
accordance with all federal, institutional, and ethical guidelines.
National Academy of Sciences (NAS)
A private non-profit organization in the United States established
by an Act of Congress and charged with providing independent, objective
advice to the nation on matters related to science and technology.
National Children’s Study (NCS)
A longitudinal study to examine the effects of the environment and
gene-environment interaction on the growth, development, and health of
children across the United States from before birth until age 21 years.
National Institute of Child Health and Human Development (NICHD)
One of the National Institutes of Health (NIH) and part of the United
States Department of Health and Human Services, the Eunice Kennedy
Shriver National Institute of Child Health and Human Development
funds and conducts research on topics related to the health of
children, adults, families, and populations.
Office of Management and Budget (OMB)
An office within the Executive Office of the President that oversees the
activities of federal agencies in the United States. The Paperwork
Reduction Act of 1980 established The Office of Information and
Regulatory Affairs within OMB to review requests it receives from federal
agencies to collect information from the public.
Personally Identifiable Information (PII)
Information about an individual including (1) any information that
can be used to distinguish or trace an individual’s identity, such
as name, social security number, date and place of birth, mother’s
maiden name, or biometric records; and (2) any other information
that is linked or linkable to an individual, such as medical,
educational, financial, and employment information.
Post Recruitment Follow-Up (PRF)
Refers to the final phase of the NCS Vanguard from March 2014
through December 2014. No new enrollments were allowed during
this phase and a common set of protocol assessments was
administered to all study participants in all study locations.
Pregnancy Probability Group (PPG)
A status assigned to age-eligible women identified during
recruitment who are not pregnant but likely to become pregnant.
In the Initial Vanguard Study, women were assigned to low,
medium, high tryer (i.e., trying to become pregnant) or high
non-tryer PPG status based on responses to a series of questions.
The PPG status determined the periodicity of follow-up calls
to determine if women became pregnant or if their PPG status
changed. In the Alternate Recruitment Strategy phase, PPG status
changed to tryer or non-tryer only.
Pregnancy Visit 1
First visit among pregnant enrolled women in ARS and PBS.
Different from the pregnancy visit terminology used in the
IVS (equivalent to T1 First or T3 First visits in IVS).
Pregnancy Visit 2
Second visit among pregnant enrolled women in ARS and PBS
(equivalent to T3Prior in IVS).
Primary Sampling Units (PSUs)
Individual components into which the target population is
divided for the first sampling stage. In the National Children’s
Study, PSUs correspond roughly to U.S. counties.
A sampling methodology where every person in the target population
has a chance of being selected into the Study, and this probability
can be calculated. Examples of probability sampling methodology are
simple random sampling, systematic sampling, stratified sampling,
sampling with probability proportionate to size, and multi-stage sampling.
Program Office (PO)
Refers to the National Children’s Study Program Office
Provider-based Recruitment (PBR)
Alternate Recruitment Substudy strategy in which women are recruited
from health care providers in contact with women who are or may
become pregnant. Women who reside in predefined geographic segments
are recruited from prenatal care provider offices.
Provider-based Sampling Feasibility Substudy (PBS)
An arm of the Vanguard Study. Provider-based Sampling arm features
include (1) county as the Primary Sampling Unit (PSU), 75 (2) providers
of prenatal care as the Secondary Sampling Units (SSUs), and (3)
recruitment of participants from selected providers with eligibility
criteria based on confirmed pregnancy, age, and residence in the
sampled PSU. This approach eliminates the recruitment limitation of
requiring participants to reside within predefined geographic segments,
and instead bases the geographic eligibility on residing within the
PSU. Three counties participated in this feasibility substudy.
A free search engine which primarily accesses the MEDLINE database
of references and abstracts on biomedical and life sciences. The
United States National Library of Medicine (NLM) at the National
Institutes of Health maintains the database.
Recruitment Strategy/Recruitment Schema
A recruitment methodology evaluated for the NCS. The NCS
recruitment strategies were: Household based recruitment
(Initial Vanguard Study [IVS]), Provider-based Recruitment
(PBR), Enhanced Household-based Recruitment (EHBR), Direct
Outreach (DO), also known as Two-tiered Recruitment (High
Intensity/Low Intensity), and Provider Based Sampling (PBS).
Regional Operations Centers (ROC)
Contract research organizations responsible for participant
retention and data collection within the given Study
locations divided into four regions (East, Central, South,
Research Materials Distribution Agreement (RMDA)
Agreement with the NICHD governing data and sample use.
The selection of a subset of individuals from a population
to estimate selected characteristics of the target population.
A listing of the target population from which a sample can be drawn.
Self-administered Questionnaire (SAQ)
A type of questionnaire, either in paper or electronic form, that a
respondent completes on his/her own without intervention of the
researchers (for example, an interviewer) collecting the data.
Secondary Sampling Units (SSUs)
Units sampled directly within primary sampling units in a multi-stage sample.
In a multi-stage probability sample, primary sampling units (PSUs)
are divided into smaller geographic areas called secondary sampling
units (SSUs) or segments. In the National Children’s Study, the
boundaries for these segments correspond to “neighborhoods or
communities”. In Direct Outreach Strategy where three levels of
sampling stages exist, tertiary sampling units (TSUs) form the
sampled segments. In PBS there were no segments, only PSUs
(which are counties).
The individuals that are selected from the target population
for participation in the Study.
Encounters of Study participants with Study personnel for the
purpose of collecting data and/or materials.
Focused clinical research studies that integrate with the Vanguard
or Main Study.
Designation code in the Initial Vanguard Study for the first
trimester visit among enrolled women (equivalent to Pregnancy
Visit 1 in the ARS phase).
Designation code in the Initial Vanguard Study for the third
trimester visit among women who have not previously received
a first trimester visit (equivalent to Pregnancy Visit 1 in
the ARS phase).
Vanguard Study Locations
The counties (or in sparsely populated areas, groups of
contiguous counties) that were selected as primary sampling
units in the first stage of sampling. They are the areas from
which Study participants were recruited in the Vanguard Study
and in which most of the community level data collections occur.
Vanguard Study/Vanguard Phase
The pilot phase of the National Children’s Study, designed to
study the feasibility, acceptability, and cost of methodological,
operational, and logistic activities, recruitment-related
activities, and Study visit assessments, for the purpose of
informing the Main Study. Refers to all Vanguard Study locations.
The various data collections performed at Study visits, including tests,
physical measurements, interviews, questionnaires, biospecimens, and