NCHS Data Release and Access Policy for
Micro-data and Compressed Vital Statistics Files
This document outlines NCHS/Division of Vital Statistics (DVS)
policy on the release of and access to vital statistics micro-data
for births, deaths, fetal deaths, linked birth/infant death, and
matched multiple births. Given changes in state laws and policies on
confidentiality with respect to the re-release of vital registration
data, NCHS has revised its micro-data release and access policy to
comply with state requirements effective
with the 2005 data year.*
The DVS revised policy as outlined here is consistent
with CDC and NCHS goals to make data available as widely as possible
while protecting respondent confidentiality, assuring data quality,
and conforming to state laws and regulations on re-release of vital
statistics data.
Data available to the public:
A. Public-use micro-data file content:
The release of public-use data generally coincides with the
publication, or follows soon after, of DVS final annual reports on
births, deaths, fetal deaths, and linked birth/infant death. DVS also
publishes preliminary reports, but these are based on incomplete data,
do not constitute a final data file, and are not released as micro-data.
Final report publication dates vary from year to year following receipt
and processing of complete data from the states and other registration
areas.
Over the years, confidentiality standards have changed for the public
release of geographic and date details on vital statistics micro-data
files. These changes are reflected in the data available in successive
time periods, as follows:
- Birth, death, and fetal death public-use micro-data files
prior to 1989 contain all counties and exact dates (year, month,
and day) of birth and death.
- Birth, death and fetal death public-use micro-data files for
data years 1989 to 2004 contain only geographic identifiers of
counties and cities with a population of 100,000 or greater, and no
exact dates. For birth, death, and fetal death files, year, month,
and day of week (e.g. Monday) are available.
- Linked birth/infant death public-use micro-data files prior
to 2005 contain geographic identifiers only for counties and
cities with 250,000 or greater population and no exact dates. Year,
month and day of week (e.g. Monday) of birth/death are available.
- Birth, death, fetal death and linked birth/infant death
public-use micro-data files beginning with the 2005 data year
will contain individual-level vital event data at the national level
only, that is, with no geographic identifiers (no State, county, or
city identifiers). These files for births, deaths, fetal deaths and
linked birth/infant death will generally include most other items
and detail from the vital record with the exception of exact dates.
Year,month and day of week (e.g. Monday) are included. Items may
vary from year to year.
- The Matched Multiple Birth file combines data from the six years
1995 to 2000 but excludes all geographic identifiers and exact dates
of births and deaths. The file also excludes year, month and day of
week (e.g. Monday). A description of the file is
viewable. The Matched Multiple Birth file for
1995-2000 and an earlier version for
1995-98 are available for downloading.
Availability: Public-use micro-data files can be downloaded
from the NCHS website on the internet; they can also be provided in
CD-ROM or DVD format and can be requested by using the
standard
procedures to request vital statistics public-use files found on the
NCHS website. Public-use files for
natality for every year beginning with 1968 are available for
downloading from the internet.
In exceptional cases involving critical issues related to public
health surveillance, the DVS Director may provide data not yet publicly
released to certain federal agencies following submission of a request
in writing to the Director, DVS.
B. Construct your own tabulations:
Data users may also access data using internet programs to construct
their own tabulations of births and deaths with geographic detail
subject to population and/or cell size limitations. Some of these
interactive systems allow users to build tables based on micro-data;
however, only tabulated data are presented to the user. Interactive
web-based systems currently available are
VitalStats ;
WONDER (Wide-ranging ON-line Data
for Epidemiological Research);
WISQARS (Web-based
Injury Statistics Query and Reporting System); and
IRHA
(Interactive Reproductive Health Atlas).
Customized files available under restricted conditions:
A. All-counties identified:
Following the process outlined below, researchers may request
customized micro-data files (birth, death, fetal death, and linked
birth/infant death) and compressed files (death only) containing
geographic detail for all States and counties for those data years with
limited (1989-2004) or no (2005 forward) geographic detail in the
public-use files.*
Data for approved projects will be provided on CD or DVD at no cost.
-
The researcher submits a project proposal to NCHS for review and
approval by NCHS and the state representative appointed by the
National Association for Public Health Statistics and Information
Systems (NAPHSIS). Some states have laws, regulations, or policies
that prohibit release of certain data items. In the course of
proposal review NCHS and the state representative will determine
whether the request contravenes any of these state limitations.
-
If the proposal is approved, NCHS will send the researcher (and
his/her contractors if federal) a Data User Agreement. All data
users associated with the research must agree to the conditions of
usage, including the following:
-
Researcher and associates will use a data file only for the
purpose stated in the proposed scope of work;
-
The researcher will return the micro-data or compressed files to
NCHS within one year unless renewal is requested and approved.
-
Project proposals should be submitted by letter, email or fax to the
Director of Vital Statistics. The proposal should include a complete
description of the proposed use of the data, including the exact
data items being requested, why the non-public use data items are
needed, the names and positions of all persons who will be utilizing
the data, and project time frames. The Director will acknowledge
receipt of the request. During the review process, the individual
making the request may be contacted by the Director or his delegate
for clarification or to obtain additional information. If a request
is denied, the Director will provide written notification to the
individual making the request. Address requests to:
-
Charles J. Rothwell, Director
Division of Vital Statistics/NCHS
Metro IV Building, Room 7318
3311 Toledo Road, Hyattsville, MD 20782
Fax: 301-458-4024; Email:
CJR4@CDC.GOV
-
If the project proposal is denied, alternative access may be
available though the NCHS Research Data Center (RDC) which has
specific procedures to follow for controlled access to micro-data
files. Use of the RDC entails costs to the data requestor. See the
RDC website
for specific procedures.
B. Availability of other files:
- Exact dates of vital events: Researchers in federal
agencies, as well as to their on-site or off-site contractors can
submit project proposals that request exact dates of vital events.
If needed, the file with exact date can also include geographic
detail. These proposals must be approved by NCHS and a state
representative. Non-federal researchers (including federal grantees)
can gain controlled access to exact dates of vital event files only
through the NCHS Research Data Center.
- The Matched Multiple Birth file with all States and
counties or exact dates included is accessible only through the NCHS
Research Data Center. See the
RDC website for specific
procedures.
_______________________
*Micro-data refers to records for
individual cases. Files released by DVS may include a single record for
each birth or death, or the file may be "compressed," replacing
identical records with a single record and the number of times that
record occurs in the file. A compressed file reduces the number of
records in the file. Compressed mortality files produced by NCHS list
year and county of death, race (white, black, other), cause of death,
and sex, use broad age groupings, and therefore do not contain as much
detail as single record micro-data files.