Amstat News - American Statistical Association

22 amstat news april 2012
Preliminary Microdata File
Available for Analysis
Jane F. Gentleman
A
preliminary microdata file of January–
September data from the 2011 National
Health Interview Survey (NHIS) is available
through the National Center for Health Statistics
(NCHS) Research Data Center (RDC). NHIS data
users can analyze these data without having to wait
for the annual final NHIS microdata release (at
about the end of June).
The NHIS is the principal source of information
about the health of the U.S. civilian noninstitutionalized
population and one of the major datacollection
programs of NCHS. Among the many
NHIS microdata and analytic products produced
by NCHS are quarterly preliminary microdata
files produced by the NHIS Early Release Program
and containing selected NHIS variables for use in
the RDC. For each data-collection year (January–
December), these files are made available three
times: in about September (with data from the first
quarter), in about December (with data from the
first two quarters), and in about March of the
next year (with data from the first three quarters).
Analysts wishing to use the files should
follow standard procedures for using the RDC.
Note that NCHS has RDCs in Hyattsville,
Maryland, and Atlanta, Georgia. NCHS RDC
data also can be accessed remotely and at U.S.
Census Bureau RDCs.
Thus, every year, NHIS analysts can use the
NCHS RDC to access selected preliminary data as
early as nine months before the annual public use
microdata release.
The January–September 2011 NHIS preliminary
microdata file contains Family Core data for
77,635 persons of all ages, Sample Child Core data
for 9,815 children, and Sample Adult Core data for
25,272 adults.
Visit www.cdc.gov/nchs/nhis.htm and www.cdc.
gov/rdc for more information. n