Download Intro QALY & need assessment

Cost-Effectiveness in Medicine
An Interactive Introduction
 Jan
J. v. Busschbach, Ph.D.
 Erasmus MC
• Institute for Medical Psychology and Psychotherapy
 Viersprong Institute for studies on Personality Disorders
 Presentations
can be found at:
 www.busschbach.nl
1
New cancer therapy
Symptoms
Drug X
Drug Y
Survival days
Days sick of chemotherapy
Days sick of disease
TWiST
300
10
100
190
400
150
30
220
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Time Without Symptoms of disease and
subjective Toxic effects of treatment
 TWiST
 Developed by Richard Gelber (statistician)
 In
search for a typical “cancer”
problem
 Often prolonged life but also a reductions in
quality of life
• At the beginning (side effects)
• At the end
 Only count the days without symptoms of disease
and subjective toxic effects of the treatment
3
Fit new therapy in fixed budget

50 patients each year (per hospital)
 Drug x: 50 x euro 1.750 = euro 87.500
 Drug y: 50 x euro 2.000 = euro 100.000

Drug budget for x or y = euro 50.000
 Number of patient
• Drug x: euro 50.000 / 1.750 = 28.5 patients
• Drug y: euro 50.000 / 2.000 = 25.0 patients
 Survival in days
• Drug x: 28.5 patients x 300 days = 8.550 days
• Drug y: 25.0 patients x 400 days = 10.000 days
 Survival in TWiST
• Drug x: 28.5 patients x 190 TWiST = 5.415 days
• Drug y: 25.0 patients x 220 TWiST = 5.500 days
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TWiST: ignores differences
in quality of life
 TWiST
 Healthy = 1
 Sick (dead) = 0
 There
is more to life than sick/health
 Make intermediate values
 Q-TWiST
• Quality of life adjusted adjusted TWiST
 How
to scale quality of life?
5
Value a health state
 Wheelchair
Some problems in walking about
Some problems washing or dressing
Some problems with performing usual activities
Some pain or discomfort
No psychosocial problems
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Time Trade-Off
 QALY:
Quality Adjusted Life Years
 Wheelchair
 With a life expectancy: 50 years
 How
many years would you trade-off for a
cure?
 Max. trade-off is 10 years
 QALY(wheel)
= QALY(healthy)
 Y * V(wheel) = Y * V(healthy)
 50 V(wheel) = 40 * 1
 V(wheel)
= .80
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EuroQol EQ-5D:
of the shelf QALY value

MOBILITY




SELF-CARE




I have no problems with performing my usual activities
I have some problems with performing my usual activities
I am unable to perform my usual activities
PAIN/DISCOMFORT




I have no problems with self-care
I have some problems washing or dressing myself
I am unable to wash or dress myself
USUAL ACTIVITIES (e.g. work, study, housework family or
leisure activities)




I have no problems in walking about
I have some problems in walking about
I am confined to bed
I have no pain or discomfort
I have moderate pain or discomfort
I have extreme pain or discomfort
ANXIETY/DEPRESSION



I am not anxious or depressed
I am moderately anxious or depressed
I am extremely anxious or depressed
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In health economics:
Q-TWiST = QALY

Count life years
 Value (V) quality of life (Q)
 V(Q) = [0..1]
• 1 = Healthy
• 0 = Dead
 One dimension

Adjusted life years (Y) for value quality of life
 QALY = Y * V(Q)
• Y: numbers of life years
• Q: health state
• V(Q): the value of health state Q

Also called “utility analysis”
9
Which health care program is
the most cost-effective?

A new wheelchair for elderly (iBOT)
 Special post natal care
10
Which health care program is
the most cost-effective?

A new wheelchair for elderly (iBOT)







Increases quality of life = 0.1
10 years benefit
Extra costs: $ 3,000 per life year
QALY = Y x V(Q) = 10 x 0.1 = 1 QALY
Costs are 10 x $3,000 = $30,000
Cost/QALY = 30,000/QALY
Special post natal care





Quality of life = 0.8
35 year
Costs are $250,000
QALY = 35 x 0.8 = 28 QALY
Cost/QALY = 8,929/QALY
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QALY league table
Intervention
$ / QALY
GM-CSF in elderly with leukemia
235,958
EPO in dialysis patients
139,623
Lung transplantation
100,957
End stage renal disease management
53,513
Heart transplantation
46,775
Didronel in osteoporosis
32,047
PTA with Stent
17,889
STIP: Short-term inpatient psychotherapy
7,677
Breast cancer screening
5,147
Viagra
5,097
Treatment of congenital anorectal malformations
2,778
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Egalitarian Concerns:
Burden of disease
1.0
0.0
A
B
C
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Implications shifting threshold
 QALY
are weighted
 Weighted QALYs are maximized
 Health is no longer the only thing maximized
 Health
status population will drop
 Differences in health will drop
 Egalitarian consideration are incorporated
 Burden
of disease becomes a criteria
 Equity
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CE-ratio by equity
15
Conclusion
 Cost
effectiveness in medicine can be
measured
 Burden of disease is also a criterion
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