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Health insurance plans vary dramatically in their
coverage of new technologies
A greater range of medical technology may be available for persons covered by traditional
indemnity insurance (as compared with an HMO) or for-profit insurers (as compared with
nonprofit plans) should their physicians choose to prescribe it. In addition, HMOs are up to three
times more likely than indemnity insurers to list the potential for decreased cost as a consideration
in favor of new medical technology coverage, reveals a study by Claudia A. Steiner, M.D.,
M.P.H., of the Agency for Health Care Policy and Research, Center for Organization and
Dr. Steiner and her colleagues at Johns Hopkins University surveyed 231 medical directors of
private HMO and indemnity insurance plans representing over two-thirds of privately insured
persons in the United States. The survey focused on laser medical technology and showed that
coverage and rationale for coverage varied dramatically among plans. For instance, coverage for
13 of 15 laser technologies ranged from 20 to 90 percent. For-profit and indemnity plans covered
two more of the different laser therapies than nonprofit or HMO plans. Overall, the researchers
conclude that a proportion of the privately insured population is ineligible for medical
technologies that are routinely available to others due to variation in coverage across plans.
Ineligibility is due at least in part to characteristics of private health care plans.
The medical directors were asked to rank the top five considerations they would use in favor of
and against recommending coverage for 3 of the 15 laser therapies: laser angioplasty—a
costly and potentially less effective alternative to balloon angioplasty for clearing coronary
obstructions; laser discectomy, a Food and Drug Administration (FDA)-approved but little
studied alternative to standard discectomy or open back surgery; and laser therapy for bladder
cancer, which is an experimental but reportedly effective treatment that has not yet been approved
by the FDA.
Clinical, economic, and regulatory issues are the factors driving most coverage decisions across
all plans, but the importance of these factors varies by type of insurance plan and the clinical
specifics of the technology under consideration. Clinical factors include increased complication
rate, experimental nature, alternative available technique, and decreased efficacy. Economic
factors include decreased cost and cost-effectiveness; regulatory factors include FDA approval.
For all three laser technologies, medical directors of HMOs were consistently more likely than
their counterparts at indemnity plans to list the potential for decreased cost as a consideration in
favor of coverage. Furthermore, medical directors of nonprofit plans were less likely to list
increased cost-effectiveness compared with medical directors at for-profit plans. There also were
significant differences in the considerations listed by larger and smaller insurers.
Details are in "Technology coverage decisions by health care plans and considerations by medical
directors," by Dr. Steiner, Neil R. Powe, M.D., M.P.H., M.B.A., Gerard F. Anderson, Ph.D., and
Abhik Das, M.S., in the May 1997 issue of Medical Care 35(5), pp. 472-489. Reprints are
available from the AHCPR Publications Clearinghouse (AHCPR Publication
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Broad exposure to other children and being poor are
linked to increased risk for childhood middle-ear
Low socioeconomic status and repeated exposure to large numbers of other children, whether at
home or in day care, are the most important sociodemographic risk factors for middle ear effusion
(MEE; acute and/or secretory otitis media) during the first 2 years of life. And contrary to
findings in many previous studies, these conditions appear to be at least as prevalent among black
as among white lower socioeconomic-status infants and certainly are more prevalent than in white
middle-class infants. These are the conclusions of a study supported jointly by the Agency for
Health Care Policy and Research and the National Institute of Child Health and Human
Development (NICHD grant HD26026).
The researchers studied 2,253 healthy infants whose middle ear status was tracked from 2 months
to 2 years of age, and who received primary care at one of two urban hospitals or one of two
small town/rural and four suburban private pediatric practices. The proportion of children
developing one or more episodes of MEE by ages 6, 12, and 24 months were 48 percent, 79
percent, and 91 percent, respectively. Overall, the mean cumulative proportion of days with MEE
was 20 percent in the first year of life and 17 percent in the second year of life.
The unadjusted cumulative proportion of days with MEE was higher among boys than girls, black
than white infants, urban than suburban infants, and Medicaid-insured than privately insured
infants. Socioeconomic status and exposure to other children most influenced the likelihood of
middle ear infections. For example, urban infants of mothers with less than a high school
education and with Medicaid insurance had a mean 31 percent of days with MEE during the first
year of life compared with only 14 percent in infants of privately insured, college-educated
mothers (insurance and education were used as the socioeconomic index). Also, during the first
year of life, urban infants with three or more other children in the household had a mean 37
percent of days with MEE, and infants in day care with five or more other children had a mean 35
percent of days with MEE. Yet those at home or in day care with no other children had a mean 22
percent of days with MEE.
More details are in "Otitis media in 2,253 Pittsburgh-area infants: Prevalence and risk factors
during the first two years of life," by Jack L. Paradise, M.D., Howard E. Rockette, Ph.D., D.
Kathleen Colborn, B.S., and others, in the March 1997 issue of Pediatrics 99(3), pp.
Asthma occurs most often among young black males
who are more likely to seek care at the hospital than a
Asthma affects 5 to 9 percent of U.S. children under 12 years of age, but the highest prevalence
of asthma continues to be among black inner-city children. Since more urban blacks than whites
tend to be poor, sociodemographic factors have been put forward as the reason for this disparity.
These factors include poorer environment (exposure to industrial effluent, air pollution, and
potential allergens like dust mites and cockroaches) and reduced access to or inadequate use of
primary care, which can prevent emergency department visits and hospitalizations for asthma. On
the other hand, blacks may simply be more biologically disposed to asthma, as suggested by a
recent study supported by the Agency for Health Care Policy and Research (HS07386). A second
AHCPR-supported study (HS07763) examines the impact of ethnic differences in primary care
use on asthma prevalence. Both studies are summarized here.
Nelson, D.A., Johnson, C.C., Divine, G.W., and others (1997, January). "Ethnic
differences in the prevalence of asthma in middle class children." Annals of Allergy,
Asthma, & Immunology 78, pp. 21-26.
Biology may tip the scale toward higher asthma risk among black children, concludes this study of
black and white children from the same middle class community. The children were of similar
socioeconomic status and had similar environmental conditions and access to medical care, but
black children still had twice the prevalence of asthma as white children.
Michigan researchers conducted a telephone survey of all families of third graders in the Detroit
suburb of Southfield to gauge asthma prevalence in this homogeneous, middle class, multiethnic
town. The survey revealed a lifetime prevalence of asthma of nearly 10 percent, which was twice
as high in black children (12 percent) as in white children (6 percent) and nearly three times as
high in boys (14 percent) as in girls (5 percent). The lifetime prevalence of probably undiagnosed
asthma (children with recurring coughs and/or wheezing that were never diagnosed as asthma)
was greater in blacks than whites (17 percent vs. 11 percent), but there was little difference
between boys and girls. These data are consistent with previous reports of asthma prevalence in
Given equal access to medical care (similar health insurance status and same area physicians), it is
unlikely that the observed differences in asthma prevalence were the result of differences in
medical care or diagnostic criteria. Rather, these findings among children in the same environment
suggest that inherent biologic differences may influence the risk of asthma, according to the
researchers. One possible mechanism is the higher blood levels of IgE, an immunoglobin
indicating an individual's likelihood of developing asthma, among blacks and males. The
researchers call for further studies to evaluate total serum IgE, ethnicity, sex, and other biologic
factors, while controlling for microenvironmental exposures that may influence the risk of asthma
in children, such as passive smoke, dust mites, and animal dander exposure in the home, which
were not accounted for in this study.
Murray, M.D., Stang, P., and Tierney, W.M. (1997). "Health care use by inner-city
patients with asthma." Journal of Clinical Epidemiology 50(2), pp. 167-174.
Primary care can prevent asthma episodes or worsening of existing ones by educating patients to
recognize what triggers their asthma, treating them with medications to prevent or control
asthma, and monitoring their asthma episodes to prevent the episodes from getting dangerously
out of control. Compared with other young patients, black adolescent males are the group most
apt to develop out-of-control asthma that lands them in the hospital. This may be affected by their
inadequate use of primary care services and their families' reliance on the emergency department
to treat asthma, concludes William M. Tierney, of the Indiana University School of Medicine's
Regenstrief Institute. Dr. Tierney and his colleagues studied the medical records of 1,788 patients
with asthma aged 5 to 34 years from a large, hospital-based, multispecialty practice in inner-city
Indianapolis from 1985 to 1992.
The researchers found that blacks had 282 outpatient visits and 138 prescription refill visits per
100 person years compared with 372 and 187, respectively, for white patients. Black males in all
but the 20- to 29-year age group had from 5 to 128 fewer scheduled clinic visits than white males.
On the other hand, compared with white males, they had a much higher age-adjusted rate of
emergency department (ED) use (13.4 vs. 11.4 visits) and hospitalizations for asthma (14.6 vs.
6.6) during the 7-year study period, with black adolescents having the highest proportion of both.
These findings suggest that black adolescent males may lack appropriate medical care for asthma,
even though black patients in this study were more likely to have Medicaid insurance than white
patients. Other barriers—such as limited access to transportation during the hours of clinic
operation—may discourage black patients from making adequate use of primary care. On the
hand, these patients may prefer the convenience of EDs that are open 24 hours a day, according
to the researchers. They call for more studies to clarify which health care and patient factors
account for higher asthma ED visits and hospitalizations among black males.
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Health Care Delivery
Various strategies would reduce but not eliminate risk
of catastrophic nursing home costs
The skewed distribution of lifetime nursing home use implies that some recent financing strategies
would fail to cover substantial amounts of care, according to a recent study by researchers at the
Agency for Health Care Policy and Research. The study found that a majority of nursing home
users (54 percent) spent less than 1 year in nursing homes, but a significant but small proportion
of users had lengthy lifetime use. Twelve percent of nursing home users spent between 5 and 10
years in a nursing home, and 4 percent were there for 10 years or more. Based on analysis of a
sample derived from the 1985 National Nursing Home Survey used to retrospectively examine
lifetime use, the study also found that most nursing home users (87 percent) had only one episode
of nursing home care during their lifetimes.
Remaining lifetime use at selected ages in 1995 was projected by correcting for improved life
expectancy and changes in the size of birth cohorts. These projections have implications for how
much nursing home use potentially would be covered by various financing strategies proposed to
ease the burden on Medicaid and Medicare and reduce out-of-pocket costs paid by families.
Recent proposals have included spreading risk by encouraging the purchase of long-term care
insurance, public entitlements that cover only the first few months of nursing home care or care
only after a substantial waiting period, and mixed public-private strategies that rely on private
insurance to cover the first part of nursing home use and the public sector to cover subsequent
The results of these projections support efforts to spread the risk of catastrophic nursing home
costs over the full population. These results suggest, however, that the risk of paying a
substantial amount out-of-pocket and eventually becoming eligible for Medicaid would remain
under a benefit covering only the first months of care. This is because about 20 percent of
community residents are projected to use more than 1 year of nursing home care. Even private
insurance with a maximum benefit of 5 years would leave a similar though smaller risk because
about 8 percent of community residents will exceed 5 years of nursing home care. Fully
one-quarter of the aggregate remaining lifetime use by 65-year-old community residents occurs
after 5 years of nursing home residence, according to the projections.
For more information, see "The amount, distribution, and timing of lifetime nursing home use," by
Christopher M. Murtaugh, Ph.D., Peter Kemper, Ph.D., Brenda C. Spillman, Ph.D., and Barbara
Lepidus Carlson, M.A., in Medical Care 35(3), pp. 204-218, 1997. Reprints are available
the AHCPR Publications Clearinghouse (AHCPR Publication No.
Stroke prevention screening for the general population
would not be cost effective
Carotid endarterectomy (surgical removal of plaque from the carotid artery) can reduce the risk of
stroke in patients with substantial carotid stenosis (70 percent of the artery blocked), who are
already experiencing mild neurologic symptoms, such as brief loss of consciousness or weakness
of limbs. The Asymptomatic Carotid Atherosclerosis Study (ACAS), reported in JAMA in 1995,
showed that this surgery was also beneficial for symptom-free patients with 60 percent or more of
the carotid artery blocked. Nevertheless, screening the general population to identify cases of
asymptomatic carotid stenosis would not be a cost-effective strategy for stroke prevention,
concludes a study supported in part by the Agency for Health Care Policy and Research (NRSA
training grant T32 HS00028).
Stroke occurs so infrequently in symptom-free persons that screening would yield only a few
surgical candidates, for whom surgery would offer a real but still modest reduction in stroke at a
substantial cost, explain Tina T. Lee, M.D., and Paul A. Heidenreich, M.D., of the Stanford
University School of Medicine, the study's principal investigators. Drs. Lee and Heidenreich and
their colleagues used published data from clinical trials to conduct a cost-effectiveness analysis on
screening a general population of asymptomatic 65-year-old men. They selected this group
because men have higher rates of stroke and carotid disease than women, and the risk of stroke
increases rapidly between 60 and 70 years of age.
The researchers compared patients screened with ultrasound for carotid disease with patients who
were not screened. Analysis that modeled the conditions and results of the ACAS revealed that,
compared with a no-screening strategy, screening asymptomatic persons would yield only 5 days
more of life per person over 30 years of age at a cost of $1,553 per person, producing a cost of
$120,000 per quality-adjusted life-year. The cost-effectiveness of screening decreased to $50,000
or less per quality-adjusted life year (considered an acceptable cost for effective clinical
interventions) only under implausible conditions—for example, a free screening instrument with
perfect test characteristics and an unlikely 40 percent prevalence of carotid stenosis in the
Details are in "Cost-effectiveness of screening for carotid stenosis in asymptomatic persons," by
Dr. Lee, Neil A. Solomon, M.D., Dr. Heidenreich, and others, in the March 1, 1997, Annals of
Internal Medicine 126(5), pp. 337-346.
Excess health care system capacity, as well as
physician behavior, may be responsible for
inappropriate practice variations
Patient race, sex, and insurance status, as well as hospital characteristics and physician
decisionmaking, have been cited as reasons for regional differences in the use of cardiac
procedures, such as angiography, angioplasty, and coronary bypass graft surgery. Two recent
studies, conducted by researchers at the Maine Medical Assessment Foundation and the Maine
Medical Center and supported by the Agency for Health Care Policy and Research (HS06813),
found a close link between practice variations and the availability of facilities and services and
prevailing testing intensity in particular regions.
The studies are summarized here. They show that communities with high catheterization
laboratory capacity, where angiographies are done, have high rates of angiography and
revascularization procedures (i.e., angioplasty and bypass surgery). Angiography—an x-ray
of the heart after injection of a contrast dye via a catheter—is considered the definitive
test required before performing revascularization surgery. Furthermore, patients treated in
communities that have diagnostically intense physicians are more apt to receive angiography than
patients in areas with less diagnostically intense clinicians, regardless of their physicians
Wennberg, D.E., Dickens, J.D., Soule, D.N., and others (1997, April). "The relationship
between the supply of cardiac catheterization laboratories, cardiologists, and the use of
invasive cardiac procedures in Northern New England." Journal of Health Services
Research and Policy 2(2), pp. 1-6.
Hospital discharge data were used to compare the per capita number of catheterization
laboratories, cardiologists, and multiprovider markets (where more than one hospital offers
coronary angiography services) with the utilization rates for angiography and cardiac
revascularization in northern New England in 1992. An increase of one catheterization laboratory
for every 100,000 residents was associated with an increase in the angiography rate of 1.62 per
Service areas with multiprovider markets were associated with an additional increase in the
angiography rate of 1.27 per 1,000 population. In addition, although angiography rates varied by
over two-fold, the ratio of invasive cardiac treatments to angiograms was constant across the 11
small areas analyzed. An increase in the angiography rate of 1 per 1,000 population was
associated with an increase of 0.46 per 1,000 population in the cardiac revascularization rate.
Variation in cardiac procedure use was unrelated to cardiologist supply or medical need. Up until
now, interventions to address variations in cardiac procedures have focused on how best to
educate physicians to follow practice guidelines and use appropriate criteria for procedure use.
But since capacity of the system is a critical driver of overall utilization patterns, efforts focused
only on physicians may be misguided, conclude the researchers. They suggest that less time be
spent micromanaging physicians and more effort be directed towards controlling the capacity of
Wennberg, D.E., Dickens, J.D., Jr., Soule, D.N., and others (1997, April). "Do physicians
do what they say? The inclination to test and its association with coronary angiography
rates." Journal of General Internal Medicine 12, pp. 172-176.
Cardiologists are more likely than internists and family physicians to use an imaging exercise
tolerance test (IETT) and coronary angiography to diagnose heart disease in patients with chest
pain and suspected coronary artery disease. Internists, on the other hand, are more likely to use
nonimaging ETTs. Regardless of specialty, populations that live in areas with physicians who are
more inclined to use sophisticated cardiac diagnostic tests are more likely to have high
population-based rates of coronary angiography.
This finding is based on a 1992 survey of 263 family practitioners, internists, and cardiologists
residing in three New England States. The survey described four clinical situations involving
patients with chest pain and suspected coronary artery disease and asked clinicians whether they
would use angiography, IETT, and ETT to test the patients.
Survey results showed that testing intensity reported by physicians was related to the
population-based rates of coronary angiography and that this relationship even cut across
specialties. Physicians who practiced in higher angiography rate areas were more inclined to
evaluate patients with coronary angiography and IETTs than those in average or low-rate areas.
No relationship was found between ETT use and coronary angiography rates. It is likely that
physicians' shared experience of patient care in local communities—through formal
exposure, referrals for testing, or informal "curbside" consultation—influences the overall
given to the population with coronary artery disease. A further explanation for the community's
"medical signature" may be the presence of a local catheterization laboratory.
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