|
PSU1 |
|
EARLY ASSESSMENT OF THE
LIKELY COST-EFFECTIVENESS OF A NEW TECHNOLOGY: A
MARKOV MODEL WITH PROBABILISTIC SENSITIVITY
ANALYSIS OF COMPUTER-ASSISTED TOTAL KNEE
REPLACEMENT
Dong H, Buxton M, Brunel University,
Uxbridge, London, UK
OBJECTIVE:
To apply a Markov model to compare
cost-effectiveness of total knee replacement (TKR)
using computer-assisted systems (CAS) with that of
TKR using conventional method. METHODS:
Nine
Markov states were identified based on the process
of the disease following TKR. Effectiveness was
expressed by QALYs. The length of a cycle was set
at one month, a discount rate of 3.5% was used for
both cost and effectiveness. The simulation was
carried out initially for 120 cycles, starting
with 1,000 TKRs. After this, a probabilistic
sensitivity analysis was carried out using Monte
Carlo approach of 10,000 iterations. RESULTS:
For
the patients who had TKR using conventional
technique the cumulative serious complication rate
was 87.3%, the minor complication rate 135.9%, the
complex revision rate 5.1%, the simple revision
rate 2.6% and the all-cause mortality 37.1%. For
the patients after TKR using CAS, the cumulative
rates were 58.1%, 136.5%, 3.6%, 1.9% and 37.1%,
respectively. The incremental cost-effectiveness
analysis shows that TKR using CAS was a long-term
cost-effective technology, but the QALYs gained
were small. After the first two years, the
incremental cost per QALY of TKR using CAS was
dominant because TKR using CAS was cheaper and
produced more QALYs. The ICER was sensitive to the
'effect of CAS', to the utility of the state
'normal healthy after primary TKR' and to the
additional cost of CAS. But it was not sensitive
to utilities of other Markov states. The average
cumulative serious complication rate, minor
complication rate, complex revision rate and
simple revision rate from probabilistic analysis
are similar as the rates from deterministic
analysis. Both analyses produced similar cost per
QALY gained, which is -d38,837 and -d39,543,
respectively. CONLUSIONS:
Compared to
conventional TKR, modelling suggests that
computer-assisted TKR is a cost-saving technology
in the long-term and may offer small additional
QALY benefits.
|
|
|
PSU2 |
|
GROWTH OF FREE-STANDING
AMBULATORY SURGERY CENTERS AND HOSPITAL SURGERY
VOLUME
Bian J, Morrisey MA, University of Alabama
at Birmingham, Birmingham, AL, USA
OBJECTIVE:
To examine the association of the
growth in free-standing ambulatory surgery centers
(ASCs) with hospital surgery volume. METHODS:
Secondary data analyses of the1992-2001 American
Hospital Association annual survey files, the 2003
Medicare Online Survey Certification and Reporting
System, an HMO penetration file, and Area Resource
Files. We construct a balanced Metropolitan
Statistical Area (MSA) panel dataset including 317
MSAs from 1992-2001. Ordinary least squares
regressions with MSA and year fixed effects are
used to control for MSA-level heterogeneity and
time trends. Three dependent variables are the
log-transformed hospital outpatient, inpatient,
and total surgery volumes. The key explanatory
variable is the number of ASC's per 10,000 people.
Other covariates include HMO penetration, hospital
concentration measured by the Herfindahl-Hirschman
Index, supplies of surgeons and physicians, and
demographic and economic characteristics. RESULTS:
From 1992-2001, hospital outpatient surgery volume
at the MSA level increasing by 23% from 58,783 to
72,111 while inpatient surgery volume decreased by
12% from 50,778 to 44,911. During the same period,
the number of ASCs per 10,000 people increased by
143% from 0.07 to 0.17, HMO penetration nearly
doubled, and hospital markets became less
competitive. In regression analysis, the growth of
ASCs was inversely associated with outpatient and
total surgery volumes (p<0.01) but was not
associated with inpatient surgery volume (p>0.10).
Other thing equal, an increase in 1 ASCs per
100,000 people is associated with a decrease of
4.1% in outpatient surgery volume or an increase
of 1.8% in total surgery volume. CONLUSIONS:
Our
study suggests that ASCs may lead to a decline in
hospital total surgery volume, largely driven by
decreased hospital outpatient surgery volume.
Additional research needs to focus on the impact
of ASCs on hospital provision of charitable care
and quality of care. |
|
|
|
|
Back to top
|
|
|
