Income, Poverty, and Health Insurance Coverage ... - Census Bureau

APPENDIX C.
ESTIMATES OF HEALTH INSURANCE COVERAGE
Quality of Health Insurance Reporting of coverage through 2.8 million Medicaid enrollees. A key
Coverage Estimates major federal health insurance finding indicating survey response
National surveys and health insur- programs The CPS ASEC data under- error in the CPS ASEC was that 16.9
ance coverage. Health insurance covreport Medicare and Medicaid cover- percent of people with an MSIS record
erage is likely to be underreported on age compared with enrollment and indicating Medicaid coverage reported
the Current Population Survey (CPS). participation data from the Centers
for Medicare and Medicaid Services
in the CPS ASEC that they were
uninsured. 2 While underreporting affects most,
(CMS)
The report found that
1 if not all, surveys, underreporting of
health insurance coverage appears
to be a larger problem in the Annual
Social and Economic Supplement
(ASEC) than in other national sur-
veys that ask about insurance. Some
reasons for the disparity may include
the fact that income, not health insur-
ance, is the main focus of the ASEC
questionnaire. In addition, the ASEC
collects health insurance information
in February through April but asks
about the previous year’s coverage.
Asking annual retrospective questions
appears to cause few problems
. Because the CPS is largely
a labor force survey, interviewers
receive less training on health insurance
concepts than labor concepts.
Additionally, many people may not be
aware that a health insurance program
covers them or their children if
they have not used covered services
recently. CMS data, on the other hand,
represent the actual number of people
who have enrolled or participated in
these programs.
The State Health Access Data
Assistance Center (SHADAC) of the
University of Minnesota has worked
Medicaid subscribers with longer and
more recent enrollment were more
likely to report coverage. Respondents
for children enrolled in Medicaid
were more apt to report coverage for
those children than for enrolled adults
within the household. Families with
lower incomes tended to report cover-
age more frequently. Individuals who
received Medicaid services during
the reporting cycle tended to report
coverage more often than individu-
als who had not received services.
Reporting differences were also apparent
among states.
when collecting income data (possibly with the U.S. Census Bureau, CMS, Phase 3 of the research project is
because the interview period is close and the Office of the Assistant further broken down into three steps
to when people pay their taxes), but Secretary for Planning and Evaluation that attempt to account for discrepit
may be less than ideal when asking (ASPE) on a research project to evalu- ancies found in Phase 2 between the
about health insurance coverage. ate why CPS ASEC estimates of the MSIS records and the CPS ASEC files.
Compared with other national sur- number of people with Medicaid are These steps focus on determining
veys, the CPS estimate of the number lower than counts of the number of the number of enrollees who were
of people without health insurance people enrolled in the program from out-of-scope for the 2001 March CPS
more closely approximates the num- CMS. Reports from all four phases of interview (people living in instituber
of people who are uninsured at a the research project are available from tions and other group quarters are not
specific point in time during the year the Census Bureau’s Web site at eligible for CPS ASEC interview; MSIS
than the number of people uninsured . counts all people, regardless of their
for the entire year. For a comparison
of health insurance coverage rates
from the major federal surveys, see
How Many People Lack Insurance and
for How Long? (Congressional Budget
During Phase 2, files from the
Medicaid Statistical Information
System (MSIS) were linked with the
CPS ASEC files and the individual
living situation). Phase 3 narrowed the
gap between CPS ASEC estimates and
MSIS files by 1.0 million, to 1.8 million
Medicaid enrollees.
Office, May 2003). records were compared. The report Phase 4 consisted of repeating the
from Phase 2 showed a gap between Phase 2 process using the National
CPS ASEC estimates and MSIS files of 2 For consistency purposes across the MSIS
and the CPS, SHADAC removed all MSIS enrollees
who received only partial coverage, those who
had died before the CPS reporting cycle, and
1 CMS is the federal agency primarily respon- all duplicate person records. Also, all Children’s
sible for administering the Medicare and Medic- Health Insurance Program (CHIP) enrollees were
aid programs at the national level.
removed from the MSIS count.
U.S. Census Bureau Income, Poverty, and Health Insurance Coverage in the United States: 2009 69