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OCR for page 16
LIZ Introcluction
Medical care has changed dramatically
in recent decades; it has become more ef-
fective, more costly, and more ambitious.
Changes have been impelled by new devel-
opments in biology, molecular biology,
pharmacology, chemistry, physics, bioen-
gineering, materials science, computing,
and other scientific and technical fields.
Medical advances have meant new medi-
cal technologies.
New technologies force changes
throughout the system; old procedures are
discarded, new ones replace them (perhaps
too soon or too late), the definition of what
is accepted medical practice shifts, third-
party payers pay for medical interventions
that were earlier unknown and they stop
paying for some superseded ones, textbooks
are revised, medical school curricula
change, and old equipment is replaced
with new.
This chapter was prepared by Lincoln E. Moses
and Frederick Mosteller based on a document drafted
by David Banta and Donald Young. David Banta con-
tributed the material for the examples on electronic
fetal monitoring, the computed tomography scanner,
drug treatment for hypertension, and hysterectomy.
16
The expanding gap between the health
care that can be provided by the available
financial resources and the health care that
could be provided if there were no finan-
cial constraint makes it increasingly neces-
sary that the health care technologies to be
available and the conditions of availability
be chosen knowledgeably.
One might hope that such selection pro-
cesses would be guided by an orderly, well-
conceived, unified system of testing and as-
sessing the new, comparing it with the old,
and moving forward as warranted by
valid, reliable, evaluative information.
That hope is at present only partially ful-
filled.
Prompt and valid assessment of medical
technology is important both to individuals
and institutions. The use or nonuse of a
new drug, device, or procedure directly
concerns two individuals, the patient and
the physician. The hospital, manufactur-
ing firms, and insurance companies must
all make and unmake various arrange-
ments when new technology replaces old.
Elucidation of medical technology assess-
ment thus demands analysis that contem-
plates both the individual and the social in-
terests.
OCR for page 16
INTRODUCTION
Two examples of the impact of technol-
ogy assessment illustrate the contribution
to be made to disease prevention and to en-
hancing the quality of patient care.
POLIO
Paralytic poliomyelitis used to strike
many children, usually during the sum-
mer; swimming pool and other recreation
facilities often would close because of a po-
lio epidemic. The Salk vaccine was in-
vented to prevent polio, though no one
knew how effective it could be. The idea of
a large public test of a vaccine on children
was remarkable in itself, though having a
President, Franklin D. Roosevelt, who had
been afflicted with the disease lent sub-
stantial support to the trial.
To be convincing, such a trial had to be
large because the annual rate of this disease
was about 50 per 100,000 population but
this number varied widely from year to
year and from place to place. An unusual
feature was that it struck well-to-do neigh-
borhoods more often than lower-income
groups. Less-hygienic living conditions are
believed to lead to earlier childhood expo-
sure to the virus while the immunity con-
ferred by the mother still protected the
child. It is also true that less educated and
less well-to-do groups volunteered less of-
ten to participate in such investigations.
Originally the study design proposed was
to vaccinate children in grade 2 and com-
pare them with children not vaccinated in
grades 1 and 3. Some state health depart-
ment officials objected that such a loose de-
sign might leave uncertainty no matter
how the study results came out. They
would not let their states participate with-
out a randomized controlled study. In the
end, both studies were carried out, and the
results show the wisdom of having the
tighter control.
The placebo controlled experiment had
201,000 children in the placebo and in the
vaccinated groups and 339,000 who were
1 ~
not inoculated. The resulting rates of para-
lytic polio per 100,000 population (using
laboratory determination) among the vac-
cinated groups was 16 and among the pla-
cebo group was 57. Those not inoculated
had a rate of 36, which was considerably
lower than the rate of 46 for the controls in
grades 1 and 3 of the other study. The lat-
ter were not selected by their refusal to
participate and thus included all groups.
The reduction from 57 to 16 was substan-
tial and led to widespread use of this and
other vaccines in the United States and
elsewhere and to a very diminished rate of
paralytic polio (Meter, 1978~.
SURGICAL PROCEDURE
A landmark assessment of a surgical
technology was carried out on relatively
few patients by Cobb et al. (19S9) and by
Dimond et al. (1958) in separate but nearly
simultaneous experiments. Barsamian
(1977) points out that as a treatment for
angina pectoris the surgical procedure of
internal mammary artery ligation was rap-
idly introduced by surgeons in Italy and
the United States, theorizing that the oper-
ation would reduce pain by shunting blood
into the coronary circulation. Early re-
ports from operations indicated consider-
able success. Barsamian said that the oper-
ation was introduced rapidly because it
was safe (could be done under local anes-
thesia), simple for the surgeon to learn and
carry out, and much needed for a large
population of patients with coronary ar-
tery disease. Measuring effectiveness,
though important, was not a major activ-
ity for surgeons in the 1950s. An enthusias-
tic report in the Reader's Digest (Ratcliff,
1957) sent many patients to surgeons ask-
ing for the operation.
Cobb applied the operation to 17 pa-
tients; for 8 the real operation was carried
out, and these patients reported a 34 per-
cent subjective improvement in the first 6
months following surgery; 9 patients had a
-
OCR for page 16
18
sham operation (which included every-
thing in the real procedure except tying off
the arteries), and these patients reported
42 percent subjective improvement. Di-
mond gave the real operation to 13 pa-
tients, 10 of whom showed substantial im-
provement, while 5 patients getting the
sham operation all reported significant im-
provement.
Barsamian (1977) said that this test of
this operation forced recognition of the
possibility that surgery or medicine could
have a placebo effect. From this followed
the demand and acceptance of controlled
studies of surgery.
Much of the nation's finest scientific and
technological talent conducts research in-
tended ultimately to improve the health of
Americans. The importance of basic re-
search for these purposes is well under-
stood, and both the National Institutes of
Health and industry invest heavily in it.
The work of development also is well rec-
ognized. Less appreciated is the bridge in
the road from basic research to beneficial
use for human beings, namely, technology
assessment. One might expect that, with
all the research and development that is ac-
complished, any product, device, or sys-
tem produced would automatically be
beneficial and that the invisible hand of
marketplace economics would make a new
technology cost-effective. This expectation
brings frequent disappointments. For ex-
ample, in the area of surgery and anesthe-
sia, Gilbert et al. (1977) found that less
than half of the surgical innovations
brought to careful testing in a randomized
controlled trial were regarded by their as-
sessors as successful. In addition, Gilbert et
al. (1977) and Grace et al. (1966) show
that weakly controlled studies tend to fa-
vor innovations more than do well-
controlled studies. Gittelsohn and Wenn-
berg (1977) find that small similar areas
of a state have great variation in the fre-
quency of performance of such surgical
procedures as tonsillectomy, appendec-
ASSESSING MEDICAL TECHNOLOGY
tomy, and hysterectomy. Such variation
raises questions about the appropriate level
of use of these operations. Thus technology
assessment is necessary to verify that inno-
vations do or do not work in practice. Cost
comparisons and social consequences also
require technology assessment.
It is not obvious that the step of technol-
ogy assessment is required, nor are such as-
sessments easy to make. Indeed, in some
areas it is not known how to do them. Be-
cause the necessity for this step is not
widely appreciated, the nation has not
thoroughly developed a system for doing
it, though many groups contribute to a
partial effort, as will be explained in Chap-
ter 2 and in greater detail in Appendix A.
Such efforts are needed, but also costly. It
is the committee's belief that additional
funds are required for technology assess-
ment and that these incremental funds
should come from the health dollar. In the
matter of drugs and devices that the Food
and Drug Administration regulates, indus-
try pays for testing for safety and efficacy,
and the public ultimately pays when prod-
ucts are marketed. In other matters, such
as cost-effectiveness and downstream con-
sequences, the health system as a whole is
involved with no natural agency or organi-
zation to give support to these efforts. For
example, market forces like those that sup-
port assessment of drugs do not exist for
surgical procedures.
The nation requires a systematic ap-
proach to technology assessment. A strat-
egy and an organization for setting priori-
ties is needed as well. Given the priorities,
mechanisms are needed for actually mak-
ing the assessments and implementing
their findings. Finally a method is needed
for paying for many of the needed assess-
ments. As with any large-scale technologi-
cal enterprise, it is necessary to maintain a
strong body of professional personnel to
carry out the assessments, and they must be
encouraged to conduct work of high qual-
ity and develop new techniques as re-
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INTRODUCTION
quired. Although in some areas parts of
this overall process are in place and con-
tribute well to the nation's health, the sys-
tem as a whole has major gaps and defi-
ciencies, which will be described.
Simply knowing the outcomes for the
health care system and their relation to the
treatments and diagnoses employed might
help in designing a more economical and
effective system. Just now a strong link
that connects outcome to care is not
known. Partly this comes from not know-
ing how to set up such a system. A vast,
sprawling monitoring system cannot be
what is needed. Some keen minds should
think about better indicators that relate
care and outcome. Part of the trouble is
that much of the current health care sys-
tem contributes to quality of life rather
than to morbidity and mortality. By and
large, accomplishments are not assessed in
these softer areas, and so medicine does not
get nearly the credit due for these contribu-
tions to comfort and convenience. Part of
the difficulty arises from the fact that the
health delivery system is itself a dynamic
process applied to a changing population.
We would not have it otherwise, but it
helps to explain how hard outcome studies
for whole populations must be. Having
mentioned this larger problem, we turn
back now to the narrower ideas of technol-
ogy assessment.
The questions of who should carry out
assessments, how they should be done, and
who should pay for them are complicated
and political and have no simple answers.
Consequently the study described here was
conducted. This report addresses the
present state of the assessment of medical
technology, gives attention to processes,
problems, interested parties, successes, and
failures, and finally points to some needs
and opportunities for improving the
present system of medical technology as-
sessment.
19
EXAMPLES OF TECHNOLOGY
ASSESSMENT
For examples, this section begins with
brief sketches of how five medical technol-
ogies have recently made their entrance
into medical practice. A number of com-
mon themes recur, and these will help to
shape a systematic treatment of the sub-
ject. Because medicine moves rapidly, fur-
ther work will have been done on the prob-
lems treated in these examples by the time
this work is published. The purpose here is
not to publish the latest information but to
give a feel for the varieties of technology
assessment that arise.
Electronic Fetal Monitoring
Electronic fetal monitoring (EFM) is a
technologic step beyond the stethoscope for
monitoring the heart rate of the fetus dur-
ing labor and delivery. EFM enables eval-
uation of fetal heart rate patterns in rela-
tion to uterine contractions and facilitates
detection of certain types of abnormal pat-
terns. Concerns about preventable perina-
tal mortality and brain damage led investi-
gators to seek a more reliable and valid
method of following fetal status during la-
bor (Banta and Thacker, 1979~. Advances
in electronics during World War II made
electronic fetal monitors feasible, as first
demonstrated by a team at Yale Univer-
sity. Such monitors became available on
the market in about 1968, and their use
spread rather quickly into most of the ob-
stetric units in the United States. By 1980
about half of the deliveries in this country
were electronically monitored (Placek et
al., 1983a,b).
But in the mid-1970s electronic monitor-
ing already had become controversial be-
cause it was suspected of being associated
with inappropriate cesarean sections. This
question stimulated several randomized
clinical trials (RCTs) (Haverkamp et al.,
1976; Renou et al., 1976; Kelso et al.,
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20
1978; Haverkamp et al., 1979; Wood et
al., 1981~. Although the trials consistently
found no reduction in fetal or infant mor-
tality from use of the electronic monitor as
compared with auscultation, they did sug-
gest an association with increases in cesar-
ean delivery rates. The basic problem with
these RCTs is that they were all too small.
Any beneficial effects of EFM would be so
slight as to require very large studies to cie-
tect them. Another shortcoming of the
RCTs is that none included low-birth-
weight fetuses (including prematures),
who are at greatest risk of mortality and
morbidity. More recently, a trial in about
13,000 low-risk women in Dublin, Ire-
land—a sufficient number to yield valid
results has found no benefit in terms of
reduced mortality from EFM but has sug-
gested a decrease in neurolo~ic damage
and a dramatic decrease in numbers of in-
fant convulsions with monitoring (Inge-
marsson, 1981; McDonald et al., 1983~.
Also the Dublin trial found no difference in
cesarean rates for the monitored groups.
The risks associated with electronic
monitoring are of concern. These range
from infection and hemorrhage to a possi-
ble correlation with the incidence of cesar-
ean section, which would be the greatest
risk. The rate of cesarean sections in the
United States was 4.5 percent of deliveries
in 1965, but rose steadily to about 18 per-
cent in 1980 (Placek et al., 1983a,b).
EFM also is expensive. Banta and
Thacker (1979) estimated an annual cost of
such monitoring at $411 million, including
indirect costs such as those of cesarean sec-
tions and other complications. Cohen
(1983), using a more thorough method of
estimation, projected annual costs of from
$210 million to $385 million. (These stud-
ies however do not include the possible
benefits of preventing necrologic damage. ~
Electronic fetal monitoring is a good exam-
ple of inadequate evaluation. More than 15
years after its introduction, more work is
needed to define its appropriate use. One
ASSESSING MEDICAL TECHNOLOGY
RCT is now being done in low-birth-
weight infants and may answer some ques-
tions. In the meantime, a risky and costly
procedure continues in widespread use.
Computed Tomography Scanning
The computed tomography (CT) scan-
ner is a revolutionary diagnostic device
that combines x-ray equipment with a
computer and a cathode ray tube display
to produce images of cross sections of the
human body (Office of Technology Assess-
ment, 1978~. The CT scanner was the
result of decades of research in such fields
as mathematics, computer applications,
and x-ray tomography. During the 1960s
several people in the United States realized
that it would be possible to develop a medi-
cal diagnostic device based on this re-
search, but they were unable to interest ei-
ther industry or government. Late in that
decade, Hounsfield, working at EMI Ltd.
in England, was able to convince his com-
pany to develop a prototype device
(Hounsfield, 1980~. The British Depart-
ment of Health and Social Services also
contributed some funds to the project. The
first demonstrations were held at interna-
tional radiology meetings in 1972, and the
device was rapidly accepted by the medi-
cal community. The importance of the
technological advance was recognized by
the award of the Nobel Prize in medicine to
some of the developers.
Plaudits notwithstanding, the CT scan-
ner has come to symbolize the problem of
high-cost medical technology (Banta,
1980~. In part, this was because of the ra-
pidity of its spread in industrialized coun-
tries. In part, it was because of its expense:
the typical scanner cost $300,000 or more
in 1973 and by 1984 it cost almost
$1,000,000. The United States now has
more than 2,000 scanners, representing a
capital investment of more than $1 billion.
Operation of the scanners costs the United
States at least another $1 billion annually.
OCR for page 16
INTRODUCTION
CT scanning is such a radical departure
from conventional radiographs that it will
take years of research for its proper roles to
be assessed in different parts of the body
and in different disorders.
Although many evaluations of CT scan-
r~ing have been done, few studies have ad-
dresse`1 a fundamental question: For what
kinds of patients is application of this diag-
nostic technology worth its costs? (Wag-
ner, 1980~. When dealing with diagnostic
technologies, answering this question re-
quires answering another question: How
does a particular technology fit into an op-
timal diagnostic process for a given condi-
tion? In other words, which diagnostic
technologies should be used in a particular
patient who needs to have a diagnosis es-
tablishe~l? The importance of this question
may be illustrated by data indicating that
millions of CT head scans were done each
year for people with uncomplicated head-
aches until CT was better evaluated.
The United States now faces the emer-
gence of nuclear magnetic resonance imag-
ing, which is another example in the se-
quence of technology development. With-
out better evaluative studies for this and
other new technologies, a great deal of
money might be wasted on inappropriate
diagnostic tests, and important opportuni-
ties might be missed to do diagnostic tests on
people who truly need them.
Drug Treatment for Hypertension
Hypertension, or high blood pressure, is
the most common chronic disease in the
United States. Estimates are that about 60
million people in this country have definite
or borderline hypertension (Levy, 1982~.
People with high blood pressure are more
likely to have strokes, heart disease, and
kidney failure than people with normal
blood pressure.
Hypertension can be controlled by drug
treatment. In the late 1960s, the Veterans
Administration supported a multi-institu-
21
tional RCT of treatment for men with the
drugs hydrochlorothiazide, reserpine, and
hydralazine. The control group was given
placebos. The drug treatment was remark-
ably effective for men with diastolic pres-
sures higher than 105 mm of mercury. For
example, strokes were reduced by 75 per-
cent, and congestive heart failure, renal
failure, and dissecting aneurysm occurred
only in the control group (Veterans Ad-
ministration, 1967, 1970~. The growing
use of drug treatment for high blood pres-
sure has been considered to be one of the
factors that has led to a falling rate of death
from heart disease in this country (Havlik
and Feinleib, 1979~.
However, although a growing percent-
age of people with high blood pressure are
being treated, many still are not. Recent
surveys done in Connecticut, South Caro-
lina, Maryland, and California have
shown that 18 to 28 percent of those with
definite hypertension were unaware that
they had the disease, and that another 21
to 34 percent were aware but were not re-
ceiving adequate therapy (National Center
for Health Statistics [NCHS], 1983~. Thus,
very positive results of an evaluation of
drug therapy have not yet been fully im-
plemented nationally and people are still
dying of cardiovascular disease at an un-
necessarily high rate.
Mild hypertension is a different prob-
lem. Clinical trials have not given clear-
cut evidence as to whether people with
diastolic pressures under 95 mm of mer-
cury should be treated (Hypertension
Detection and Follow-up Program Coop-
erative Group, 1982~. Yet, surveys of phy-
sicians have shown that they frequently
prescribe drugs for mild hypertension
(Guttmacher et al., 1981~. More recent
clinical trials have not resolved this scien-
tific issue for patients under 50 years of
age, which is of concern because antihy-
pertensive drug treatment is not benign
(Joint National Committee on Detection,
Evaluation, and Treatment of High Blood
OCR for page 16
22
Pressure, 1984~. Complications associated tion
with drug treatment include dizziness, im-
potence, and general tiredness. Side effects
can be minimized by careful medical su-
pervision, but it is doubtful whether such
care is usually available. The practice of
treatment of mild hypertension has been
criticized as seeking the technological
rather than the social solution to disease,
because the incidence of high blood pres-
sure is often associated with stressful life
situations (National Institutes of Health
1979j. The drug industry's promotion of
drug treatment for mild hypertension also
has been criticized. In short, drug treat-
ment for hypertension is one of the most
important medical advances of this cen-
tury. However, questions remain that can
be answered only by good assessments.
Hysterectomy
Surgical removal of the uterus is per-
formed more often than any other major
operation in the United States. The Na-
tional Center for Health Statistics esti-
mates that 704,800 hysterectomies were
performed in the United States in 1978,
compared with 678,000 in 1976. The 1978
rate is 817.3 per 100,000 women 15 years
of age and older (Korenbrot et al., 1980~.
More recent figures for 1980 and 1981 indi-
cate rates of 563 and 573 per 100,000
women, respectively (Easterday et al.,
1983~. At such a rate, more than half of
American women would have their uterus
removed by age 65. The high rate of hys-
terectomy is not peculiar to the United
States (L. J. Kozak, National Center for
Health Statistics, personal communica-
tion). Canada and Australia have rates ap-
proximately as high as those in the United
States. It is frequently alleged that many of
these hysterectomies are unnecessary.
Medical indications for hysterectomy
are not standard, and this leads to varia-
tions in the rate. Wennberg and Gittelsohn
(1973) have demonstrated a strong correla-
ASSESSING MEDICAL TECHNOLOGY
between the numbers of surgical spe-
cialists and the number of operations per-
formed in different districts in Vermont.
Cross-national studies comparing the
United States, the United Kingdom, and
Canada have demonstrated a relationship
between the number of surgeons and oper-
ations, including hysterectomy (Bunker,
1970; Vayda, 1973~.
Some indications for hysterectomy, such
as for cancer, are well accepted. The con-
troversial indications are its use as a means
of sterilization and its use to prevent cancer
of the uterus. About 30 percent of hysterec-
tomies done in the United States are done
for these indications (Korenbrot et al.,
1980).
Hysterectomy has significant risks.
Death occurs in 0.1 to 0.4 percent of cases.
If 30 percent of hysterectomies are elective
in the United States, a 0.1 percent mortal-
ity would mean 210 deaths among this
group. Much more frequent are nonfatal
operative complications, including bleed-
ing, infection, and complications of trans-
fusion and anesthesia. In a meta-analysis
of published reports carried out at Stan-
ford University, 73 percent of women with
nonemergency abdominal hysterectomy
had some degree of morbidity, and more
than 7 percent had moderate to life-threat-
ening complications (Korenbrot et al.,
1980~.
The financial costs of hysterectomy are
high. A hysterectomy was estimated in
1978 to cost from $1,700 to $2,600 in direct
medical care expenses (Korenbrot et al.,
1980~. This figure does not include the
costs of complications, nor does it include
indirect costs such as lost work or psycho-
logical costs. Several cost-effectiveness
studies have been done, and none found
hysterectomies cost-effective for steriliza-
tion or prevention of uterine cancer. The
studies have found large immediate risks
and costs, with some future benefits. In a
recent study, Sanberg et al. (1984) found
net costs to range per year from $1,200 to
OCR for page 16
INTRODUCTION
$3,700 and net increases in life expectancy
were on the order of 6 to 8 months.
Thus, hysterectomy is frequently used
for questionable indications. Many data
that would be useful in assessing this kind
of use are lacking, and available data do
not strongly defend it. This raises questions
of who will do the needed research and
what will be done about the frequency of
the procedure. Assuming that women are
choosing the procedure voluntarily, it may
be appropriate for society to decide that
some benefits, such as the small, yet un-
proved likelihood of cancer prevention, are
not worth the large immediate costs.
Medical Information System
E1 C amino Hospital, a medium-sized,
nonteaching, community hospital, in-
stalled in 1971 a Technicon Medical Infor-
mation System (TMIS), which processed a
broad range of medical and administrative
data. Two studies of it by Battelle Colum-
bus Laboratories were funded by the Na-
tional Center for Health Services Research
(Coffey, 1980~. The first examined the ef-
fect of TMIS on organization and adminis-
tration. The second study, described here,
measured the impact of TMIS on total hos-
pital costs. This example illustrates a par-
tial evaluation of a support system rather
than of a treatment or of a diagnostic tech-
nology. A more complete evaluation might
also study changes in the quality of care.
23
(Although the study presented here dis-
cusses costs, these may actually be some
form of charges.)
Costs were examined in two ways, one
excluding the cost of TMIS and the other in-
cluding its operational cost. The investiga-
tors used three indices: cost per patient, cost
per patient day, and cost per month. Cost
per patient measures the social cost, expense
per patient day keys into health insurance
carriers' procedures, and monthly expenses
give an overall picture of the hospital
budget. Expenses were broken down ac-
cording to nursing care, ancillary services,
and support services. The study covered a 6-
year period: 2 years before TMIS, 1 year of
installation, and 3 years of full operation.
Multiple regression methods and four
control hospitals were used to adjust for
variables that could not be controlled.
Table 1-1 shows the overall outcome of
changes in costs associated with the opera-
tion of the TMIS in its third year of opera-
tion. These changes exclude the cost of the
TMIS itself. The reduced cost per patient
for nursing was said to be due to reduced
paperwork and to a reduction in the nurs-
ing work force.
Another important impact was that
faster turnaround time on tests and execu-
tion of orders led to a reduction of 4.7 per-
cent in length of hospital stay. This was re-
markable because E1 C amino already had
a very low average length of stay.
The increase of 4.5 percent in support
costs per patient was, nevertheless, unex-
TABLE 1-1 Partial Impact of TMIS (Excluding Its Cost) on Three Measures of Cost at E1
Camino Hospital, by Department
Change in Cost Change in Cost Change in Cost
Department per Patient per Patient Day per Month
Nursing _ 5.0a - 2.0 5.3
Ancillary - 2.4 1.1 7.7a
Support 4.5 7.5a 14.3a
All departments - O.6 2.3 9.2 a
Statistically significant beyond the 5 percent level.
OCR for page 16
24
pected. Some increase was due to increased
medical records work and some to a deci-
sion unrelated to TMIS to increase nurses'
training. The investigators believed that
changes in support costs should not be at-
tributed to the TMIS, and so they analyzed
the data in two ways. Table 1-2 shows the
results analyzed with an adjustment for
these support cost charges (Method 1) and
a second analysis that shows exactly what
happened with adjustment for support
costs (Method 2~. The TMIS costs are
treated separately, and the two analyses
are presented in Table 1-2.
The 4.5 percent difference between the
monthly costs at every level of both meth-
ods of calculation suggests that the TMIS
costs 4.5 percent of the total budget. The
investigators speculate that this means that
the hospital may have to absorb 40 percent
of the cost of the system,with 60 percent
covered by improvements in productivity.
Earlier studies had shown reduced error
rates on orders and tests and improved
completeness and accuracy of patient data.
Thus, the medical benefits might justify
the additional costs, but this issue was not
part of the study.
The main conclusions were that (1) nurs-
ing costs per patient had been reduced by
about 5 percent; (2) average length of stay
was reduced by about 4.7 percent, even
ASSESSING MEDICAL TECHNOLOGY
though E1 C amino started with a very low
rate; (3) TMIS raised overall costs per pa-
tient by 1.7 or 3.9 percent depending on
whether one ignores support department
increases; (4) hospital costs rose 3.2 percent
per patient day; and (5) adjusted overall
monthly expenses rose 7.8 percent largely
because of increased patient flow. Caution
should be observed in transferring this ex-
perience because management informa-
tion systems have become more fully devel-
oped since then. The outcomes might
depend heavily on the patterns of work
and the organizational structure of the in-
stitution installing a management informa-
tion system. One would want to assess such
a system to see which aspects were working
well and which were not; the outcome of
the assessment may be unique to the insti-
tution. Other studies assessing information
systems in hospitals have been carried out
by Rogers and Haring (1979) and Haring et
al. (1982~.
This analysis clearly shows that intro-
ducing a new system has extensive and of-
ten unexpected ramifications. Tracing the
consequences is a difficult task.
SOPHIE LESSONS FROM THE EXAMPLES
It can be seen that medical technology is
a term that embraces quite a range of ac-
TABLE 1-2 Overall and Partial Impact of TMIS on Annual Expense of All Departments at
E1 Camino Hospital During 1975, by Two Methods
Unit of
Measurement
TMIS Impact
Including TMIS
Cost (%)
TMIS Impact
Excluding TMIS
Cost (%)
Method 1. Adjusted for support costs
Per patient 1.7 - 2.8
Per patient day 3.2a -1.3
Per month 7.Sa 3.3a
Method 2. Unadjusted Results
Per patient 3.9 - 0.6
Per patient day 6.8 2.3
Per month 13.7 9.2
aStatistically significant beyond the 5 percent level.
OCR for page 16
INTRODUCTION
tivities. For consistency the committee fol-
lows the usage of the Office of Technology
Assessment (OTA, 1982), which uses the
term to refer to "techniques, drugs, equip-
ment, and procedures used by health-care
professionals in delivering medical care to
individuals, and the systems within which
such care is delivered."
The five examples illustrate some of the
dimensions along which medical technol-
ogy varies. Two examples, electronic fetal
monitoring (EFM) and computed tomog-
raphy (CT), are diagnostic; two, hysterec-
tomy (Hx) and drug treatment for hyper-
tension (DTH), are therapeutic; one, in-
formation processing, is a supporting
technology; one is a drug, one is a surgical
procedure, three are strongly equipment
linked.
At least six issues occur in three or more
of the five examples:
1. Risks how probable and how severe
are associated adverse effects? (EFM,
DTH, Hx)
2. Appropriateness are there indica-
tions for use in at least some patients? (All
five)
3. Benefits what are they? How large?
How sure? (All five)
4. Insufficient evidence in the extant
studies. (EFM, CT, Hx, DTH)
5. Rapidity and scope of diffusion into
clinical use. (The first four suggested the
possibility of too rapid and extensive ac-
ceptance; in addition, DTH suggested un-
derutilization. ~
6. Cost, both to patient and as a social
investment. (All five)
Two further issues should be adduced
here, although we do not undertake to
measure their intensity in the examples:
7. Assessment of costs, risks, and bene-
fits can be difficult, and requires informa-
tion that is hard to get or lacks conceptual
clarity about subtle matters such as quality
of life.
25
8. Ethical questions are inherent and
include equity of access to new technology,
reasonableness of allocation of scarce med-
ical resources, and mistreatment of some
patients because of incorrectly established
indications, etc.
These eight issues constitute problems
that are addressed by technology assess-
ment, a term that we now can treat more
specifically. The term assessment of a med-
ical technology is used here to denote any
process of examining and reporting proper-
ties of a medical technology used in health
care, such as safety, efficacy; feasibility;
indications for use; cost and cost-effective-
ness; and social, economic, and ethical
consequences, intended and unintended.
Comprehensive assessment examines all of
these issues.
This language is chosen deliberately; it
admits of an assessment that is concerned
with only a portion of the full spectrum of
properties. Some assessments will be only
of the safety and efficacy of a technology
while others may be more inclusive, add-
ing information about costs and social and
ethical impacts. This is intended, because
much of assessment activity is partial in its
scope. As will be seen, various participants
in the health care system find different
properties to be salient, focusing their stud-
ies narrowly to address the questions that
interest them.
COMPREHENSIVE TECHNOLOGY
ASSESSMENT
Assessment of medical technology is of
course a particular instance of technology
assessment as practiced by industry, gov-
ernment, consumers, and various agencies
in other fields of applied technology such
as transportation, agriculture, or housing.
Technology assessment generally is an im-
perfect but maturing process whose conse-
quences are exemplified in the popular
press by the occasional recall of automo-
OCR for page 16
26
ASSESSING MEDICAL TECHNOLOGY
bites, the relatively recent redesign of tiveness of coronary care units for the
bridge abutments and guard rails on high- treatment of patients with myocardial in-
ways, and the constraints imposed on nu- farction is complicated by the dramatic re-
duction in mortality from myocardial in-
farction over the last 15 years which is
partly attributable to the change in smok-
ing habits of the population at risk.
clear energy plants.
Arnstein (1977) attributes the concept of
technology assessment to Emilio Q. Dad-
dario, former congressman and founding
Director of the Office of Technology As-
sessment. Technology assessment has more
holistic implications than such usual meth-
ods of technology evaluation as clinical
trials, market research, cost-benefit analy-
sis, or environmental impact assessment.
Technology assessment ideally would be
comprehensive and include evaluation not
only of the immediate results of the tech-
nology but also of its long-term social, eco-
nomic, and ethical consequences.
A comprehensive assessment of a medi-
cal technology after assessment of its im-
mediate effects may also include an ap-
praisal of its unintended consequences,
problems of personnel training and licen-
sure, new capital expenditures for equip-
ment and buildings, and possible conse-
quences for the health insurance industry
and the social security system. Technolont
assessment provides a form of policy analy-
sis that includes as potential components
the narrower approaches to technology
evaluation. Most assessments stop with a
partial effort, and we include these when
we speak of technology assessment.
The assessment of medical technologies
presents certain qualitative and quantita-
tive differences from technology assess-
ment in other sectors. For example, medi-
cal technologies often can be assessed only
on the basis of observing acutely ill people
under conditions in which there is less than
full control of important variables and
with less than desirable characterization of
individual circumstances.
The assessment of medical technologies
often is confounded by the occurrence of
large changes in the patient or process out-
come due to factors outside of the study de-
sign. For example, the analysis of the effec-
DIFFERENT PARTIES, DIFFERENT
AIMS IN ASSESSMENTS
The Office of Technology Assessment
staff, in treating this subject, wrote (OTA
1982, p. 3~:
Medical technology assessment is, in a nar-
row sense, the evaluation or testing of a medical
technology for safety and efficacy. In a broader
sense, it is a process of policy research that ex-
amines the short and long-term consequences of
individual medical technologies and thereby
becomes the source of information needed by
policymakers in formulating regulations and
legislation, by industry in developing products,
by health professionals in treating and serving
patients, and by consumers in making personal
health decisions.
For the purposes of this work, nearly all of
health services research would be included
in this definition.
According to this statement, medical
technology assessment involves at least
four participants: a policymaker, an ad-
ministrator, a health care provider, and
the patient. The provider and the patient
can be seen as a dyed, concerned primarily
with the safety and efficacy of particular
technologies under consideration for use by
that practitioner upon that patient. A1-
though cost, equity, profit, etc., matter a
great deal to the dyed, they are not pri-
mary factors in their technology assess-
ment.
Patients should be concerned that tech-
nologies have been studied in patients simi-
lar to themselves. That aspect of equity
may be up to the dyed, not in each in-
stance, but in the sense of a general popu-
lation. Those who choose not to participate
OCR for page 16
INTRODUCTION
in studies need not expect the findings to
apply to them.
The medical scientists who test and try
out new technologies may concentrate ef-
forts mainly on one feature of the technol-
ogy. The epidemiologist may study
whether a particular adverse outcome is
systematically related to the use of a cer-
tain treatment (e. g., thromboembolism
from using high-estrogen contraceptive
pills, or vaginal carcinoma in daughters of
mothers who used diethylstilbestrol). The
diagnostic imaging specialist may want to
assess the relative or absolute information
obtained with a test (e.g., echocardiog-
raphy, radionuclide studies, ultrasound,
etc.) because it relates to the efficacy of
those technologies. Another medical scien-
tist, evaluating diagnostic or therapeutic
algorithms, may focus on a narrow ques-
tion, such as "Can the algorithm be im-
proved by introducing test Y at some
stage?"
The makers of devices, drugs, or other
medical equipment may have yet other in-
27
of safety and efficacy. Professional societies
often establish standing or ad hoc panels to
study questions relating to the appropriate
use of technologies. It sometimes happens
that different organizations reach differing
conclusions on the same issue.
Third-party payers contribute substan-
tially to medical technology assessment.
Requests for payment for a new procedure
are likely to trigger a review of the technol-
ogy. Usually, this review is not deliberately
directed at safety and efficacy, but rather
it is to help in deciding whether the new
procedure conforms to accepted practice.
A negative decision about reimbursing a
new technology will tend to inhibit its dif-
fusion. But sometimes such a decision can
stimulate further assessment studies, un-
dertaken by proponents of the technology.
Thus, it is reported (Cutler et al., 1973)
that some of the studies concerning cost-
effectiveness of routine health checkups
originated in efforts to justify the provision
of reimbursement for such checkups.
~ ~ Large employers often are major pur-
terests in assessment of their technologies. ~ ~ ~
The manufacturer of a drug, for instance,
will seek to develop information to satisfy
the requirements of the Food and Drug
Administration; both the data and the
manner in which they were acquired are
subject to regulatory review. Manufactur-
ers more generally will be concerned with
the size of the possible market for their
product, its costs as seen by the buyer, and
its strengths and weaknesses in comparison
with competitive products.
Various institutional components of the
health profession also are involved in tech-
nology assessment, and their concerns re-
late to their roles. Editors of journals influ-
ence what becomes known to readers who
rely upon their journals; the influence is
exerted both through editorials and
through decisions about which articles to
publish. Medical school teachers and text-
book authors must form, and then propa-
gate, opinions that amount to assessments
chasers of medical coverage for their em-
ployees. Extension of coverage benefits,
perhaps as an item of union contract nego-
tiation, raises the question of which exten-
sions would be most worthwhile. This may
quickly lead to comparison of the costs,
risks, likely frequency of use, and effective-
ness of several medical technologies that
are alternative candidates for new cover-
age.
Hospitals and health maintenance orga-
nizations (HMOs) often look at new medi-
cal technologies as possible major invest-
ments, including both capital costs and
costs of operation. The prospective pur-
chaser must assess this technology from
many points of view besides its costs. Its
probable revenues are of equal concern.
Questions of feasibility may be dominant:
What are the space requirements? What
training is required for personnel to oper-
ate it? Will re-education of medical profes-
sionals be called for? How about computer
OCR for page 16
28
support? Costs from the point of view of
the patient may receive little attention if
reimbursement is assured, or much atten-
tion if, as in the HMO, recovery must ulti-
mately be sought through overall increased
membership fees, reserves, or other
sources.
Some associations of hospitals and other
institutions offer to their members assess-
ment-like advice about new technologies.
Several of these are described in Chapter 2.
For example, the American Hospital Asso-
ciation (AMA) works to assist hospital ad-
ministrators facing management and in-
vestment decisions about new and existing
technologies. The AHA program evaluates
diagnostic systems, therapeutic systems,
computer technologies, and the like, but
evaluates medical procedures only as they
relate to equipment purchase or nonmedi-
cal hospital personnel. The evaluations fo-
cus on:
cost and organizational implications;
installation costs;
staffing and training requirements;
· probable number of patients affected;
· effects on other hospital resources,
such as the extent to which a technology
will enable the replacement of existing re-
sources, or the extent to which it will neces-
sitate the addition of new resources;
· clinical effectiveness: not patient out-
comes as such, but process outcomes such
as inpatient versus outpatient application,
average length of stay, etc.
Government agencies are active in med-
ical technology assessment, often through
decisions about reimbursement or about
hospital investment in large equipment.
Such assessments are concerned with eco-
nomic efficiency, as well as with safety and
efficacy, but U.S. government agencies
have generally not emphasized assessments
for economic efficiency and cost-effective-
ness. The guidelines prepared by the fed-
eral government of Canada to assist prov-
inces who request guidance in their
ASSESSING MEDICAL TECHNOLOGY
hospital investments typically have 10
components (OTA, 1980~. These compo-
nents form a checklist of considerations to
be entertained before establishing a new
unit:
· patient load;
· bed requirements;
recommended distribution;
administrative policy, procedures
and control;
.
.
services;
staff establishment and coverage;
staff training and qualifications;
specific supporting departments and
· space allocation, utilization, and spe-
cific design features;
· equipment;
· relationship with other departments
and services.
Concern with feasibility and coordina-
tion loom large in these governmental
guidelines for assessment.
The contrast between the Canadian
guidelines and the U.S. health policy state-
ments in the 1975 health planning law and
its 1979 amendments is worth noting. Title
XV of the Public Health Services Act (P.L.
93-641) Section 1502 sets forth a number of
National Health Priorities intended to
guide national planning and investment,
especially governmental, in capital facili-
ties for health care, including expensive
equipment. Among these priorities are
· provision of primary care services for
medically underserved populations, with
emphasis on rural and economically de-
pressed areas;
· coordination and consolidation of in-
stitutional health services by developing
multi-institutional systems (specialty ser-
vices such as radiation therapy, intensive
and coronary care, and emergency trauma
care are singled out for special attention);
development of multi-institutional systems
for sharing support services;
· development of health services institu-
OCR for page 16
INTRODUCTION
tions "of the capacity to provide various
levels of care. . . on a geographically inte-
grated basis."
The public policy goals also emphasize
alternative health care systems to hospi-
tals, encouraging
· the development of medical group
practice;
· the training and utilization of allied
health professionals such as nurse clini-
cians and physician assistants;
· the promotion of activities for the pre-
vention of disease, including studies of nu-
tritional and environmental factors affect-
ing health and the provision of preventive
health services.
Some additional priorities are consumer
education so that the general public might
use "proper personal health care" includ-
ing prevention; cost containment and the
"adoption of uniform cost accounting and
simplified reimbursement"; and activities
to "achieve needed improvement in the
quality of health services."
Federal Medicare reimbursement for the
capital portions of the hospital bill are de-
nied to health care institutions that expand
beds or certain programs without a certifi-
cate of need. The 1975 law approached
cost containment primarily through insti-
tutional coordination, regionalization, the
sharing of services, and nonhospital alter-
natives.
Technology assessment as a means of
achieving these goals is not given specific
mention. However, the 1979 amendments
emphasized the importance of "the identi-
fication and discontinuance of duplicative
or unneeded services and facilities" tP.L.
96-79, Section 102(a) (1) i. To the section of
the previous law promoting uniform cost
accounting and improved management
procedures for institutions offering health
services was added the words "and the de-
velopment and use of cost-saving technol-
ogy" [Section 102(a)~2~.
29
Finally, legislative bodies can be deeply
involved in assessment of medical technol-
ogy. Congress established the Office of
Technology Assessment in 1972 as an advi-
sory arm. OTA uses these words in describ-
ing its mission: "The assessment of technol-
ogy calls for exploration of the physical,
biological, economic, social, and political
impacts which can result from applications
of scientific knowledge." For medical tech-
nology this broad construction of the task
reaches far beyond safety and efficacy.
The multiplicity of organizations carry-
ing out assessments, the variety of kinds
and purposes of assessments, and the
amount spent on various kinds of assess-
ments are described in Chapter 2. That in-
ventory calls attention to the fact that no
agency has the task of attending to the
needed research for the nation, such as
noting which medical technology assess-
ments need to be carried out and assigning
priorities and financing their execution.
Appendix A supplements Chapter 2 by de-
scribing in more systematically gathered
detail the work of a set of the agencies car-
rying out assessments of medical technolo-
gies.
To lay a foundation of methods used in
medical technology assessment, Chapter 3
describes and illustrates the major meth-
ods, explains their strengths and limita-
tions, and outlines new research in each
method whose results might strengthen its
use. To help us understand how medical
technologies come to be adopted, dropped,
or ignored, Chapter 4 examines the role of
assessment, education, publications, and
other stimuli to diffusion.
The role of reimbursement in encourag-
ing and paying for the assessment of medi-
cal technologies has been much debated,
and Chapter 5 discusses some of the history
of these developments, both state and na-
tional. The international scene, at least in
principle, is a two-way street for technol-
ogy assessment, and Chapter 6 explores the
current position of the United States with
OCR for page 16
30
respect to use of international assessments.
The question of what information can be
usefully exchanged and what long-term
policies should be instituted go beyond the
purview of this report.
Chapter 7 summarizes the state of the
nation's assessment of medical technologies
and makes general recommendations for
creating a pluralistic national system. It
does not summarize the narrower recom-
mendations scattered through the report,
highlighted in the chapters, but focuses on
the gaps that now prevent the United
States from having a system and proposes a
set of gradual steps for creating one.
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