Assessing Health
and Economic Outcomes
William C. Black, M.D.
Director ACRIN Outcomes & Economics Core Laboratory
Dartmouth-Hitchcock Medical Center
Outline
• Background
• Health outcomes
• Economic outcomes
• Cost-Effectiveness Analysis
“Outcomes”
• Geography is destiny
• More is not better
• Patient preferences matter
US Health Care Expenditures
$2.50
Trillions
$2.00
$1.50
$1.00
$0.50
$0.00
1960
1970
1980
1990
2000
2010
Year
http://www.cms.hhs.gov/NationalHealthExpendData/02_NationalHealthAccountsHistorical.asp#TopOfPage
Health Expenditures by Country, 2006
Life Expectancy by Country
Country
Life Exp
Rank
Macau
84.4
1
Japan
82.1
3
Canada
81.2
7
United Kingdom
79.0
36
United States
78.1
49
Mexico
76.1
71
China
73.5
108
Iraq
70.0
145
Growth in physician services
“Outcomes”
• Determine what works
• Assess pt preferences
• Deliver appropriate care
Hierarchical Model of Efficacy
•
•
•
•
•
•
Level 1. Technical
Level 2. Diagnostic accuracy
Level 3. Diagnostic thinking
Level 4. Therapeutic
Level 5. Patient outcome
Level 6. Societal
Fryback & Thornbury. Medical Decision Making 1991;11:88-94.
Accuracy
• SE = Pr(T+| D+)
• SP = Pr(T-| D-)
• Az = Area under ROC curve
Disease
Treat
LED+B
P
No disease
LEN-C
1-P
Test positive
Disease
P
CHOOSE
Test
SE
Test negative
1-SE
Test positive
No disease
1-P
1-SP
Test negative
SP
LED+B
LED
LEN-C
LEN
Disease
No Treat
P
No disease
1-P
LED
LEN
Baseline Values
P
0.5
B, C
1.0
LEN
2.0
LED
0.0
SE, SP
0.8
Expected Utility
Treat
Test
No Treat
1.0
1.3
1.0
Limitations
• Disease spectrum
• Accuracy of test
• Natural History of dz
• Effectiveness of treatment
Randomized Clinical Trial
To ensure that observed differences in
outcome depend only on the interventions under investigation and not on
other factors that affect outcome.
Outcomes & Economic Core Lab
• Measure Health Related QOL
• Measure costs
• Analyze cost-effectiveness
Health Related QOL
• Global rating
• Symptoms
• Functional status
Health Related QOL
• Non-preference based
– Generic, e.g., EVGFP, SF-36
– Disease-specific, SAQ
• Preference based
– Direct, e.g., VAS
– Indirect, e.g., SF-6D
Measuring Preferences - Direct
• Rating scale
• Standard gamble
• Time-tradeoff
Visual Analogue Scale
Standard Gamble
Measuring Preferences - Indirect
• Quality of Well Being
• Health utilities index
• EuroQoL-5D
• Short Form -6D
SF-6D
1.
2.
3.
4.
5.
6.
Physical functioning
Role limitations
Social functioning
Pain
Mental health
Vitality
SF-6D Utility Scoring
Physical Functioning
Term
Score
PF1
-0.000
PF2
-0.053
PF3
-0.011
PF4
-0.040
PF5
-0.054
PF6
-0.111
U = 1.000 + ∑Score – 0.070
Brazier et al. J Health Econ 2002;21:271-92.
Quality Adjusted Life Year
• Measure of patient utility
• Measured on a scale of 0-1.0
• Can be assessed directly or derived
from health survey, e.g., SF-36
Quality Adjusted Life Years
Quality of Life
1.0
QALY = 0.5+0.25
= 0.75
0.5
0
0.5
Quantity of Life
1.0
Economic Outcomes
• Direct
– inpatient care
– outpatient care
– medications
• Indirect
– time and travel
Hospitalization Costs
• Triggered by patient questionnaire
• ICD-9, DRGs, and CPTs coded by MRA
• Medicare reimbursement
– Part A MEDPAR
– Part B Physician Fee Schedule
Outpatient Costs
• Triggered by patient questionnaire
• ICD-9 and CPTs coded by MRA
• Medicare Physician Fee Schedule
• Red Book avg wholesale prices
Indirect Costs
• Triggered by patient questionnaire
• Travel and other expenses
• Time from usual activities
CEA
• Societal perspective
• In-trial and lifetime horizons
• Discounting @ 3%
• Sensitivity analysis
Incremental Cost Effectiveness Ratio
ICER =
∆COSTS
∆QALYS
c
cost
II
K
IB
IA
effect
IIIA
IIIB
IV
Black. Med Decis Making 1990. 10(3): 212-4.
Comparison
STRATEGY
Do Nothing
Do Something
COST
QALYS
CER
0
0
NA
$100,000
4
$25,000
Chart Abstraction Process
Summary
•
•
•
•
•
Variation in practice
Rising costs unsustainable
Radiologic imaging target
“Outcomes” data collection essential
Role of cost-effectiveness analysis