Why use the EQ-5D?
What are the alternatives?
What are the alternatives forDirect valuation?
•Other VAS
•Time Trade-Off
•Standard Gamble
•Willingness to pay
•Difficult…
–Pairedcomparisons
–DCE etc
Visual Analogue Scale
•VAS
–Also called “category scaling”
–From psychological research
•“How is your quality of life?”
•“X” marks the spot
–Rescale to [0..1]
•Different anchor point possible:
–Normal health (1.0) versus dead (0.0)
–Best imaginable health versusworse imaginable health
Dead
Normalhealth
X
Time Trade-Off
•TTO
•Wheelchair
–With a life expectancy: 50 years
•How many years would you trade-off for acure?
–Max. trade-off is 10 years
•QALY(wheel) = QALY(healthy)
–Y * V(wheel) = Y * V(healthy)
–50 V(wheel) = 40 * 1
•V(wheel) = .8
Standard Gamble
•SG
•Wheelchair
•Life expectancy is not important here
•How much are risk on death are youprepared to take for a cure?
–Max. risk is 20%
–wheels = (100%-20%) life on feet
–V(Wheels) = 80% or .80
Willingness to pay
•Cost benefit analyis
•Revealed preferences
–Look in market howmuch subject arewilling to pay
–Different situationsgive different results
–Weighted by in income
•Conclusion:
–the validity of costbenefit analysis is notsufficient
Alternatives for indirectmeasurements
MOBILITY
I have no problems in walking about
I have some problems in walking about
I am confined to bed
SELF-CARE
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 orleisure activities)
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 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
Validated questionnaires
The Rosser & Kind Index
The Rosser & Kind index
•Criticism on the Rosser & Kind index
–Sensitivity (only 30 health states)
•New initiatives
–Higher sensitivity (more then 30 states)
•EuroQol Group
–EQ-5D-3L and the EQ-5D-5L
•McMaster University
–Health Utility Index 2 & 3
•SF-36
–SF-6D
Health Utility Index
•Developed from pediatric care
–Strong proxy versions
•Symptom driven:
–“Outside the skin” instead of “inside the skin”
•EQ-5D: “problems with daily activity”
•HUI: “Unable to read ordinary newsprint…”
•Commercial
–All user have to pay
•35 Translations
HUI 2
HUI 3
Increasing number of health states
No longer value all states
•Impossible to value all health states
–If one uses more than 30 health states
•Estimated the value of the other health stateswith statistical techniques
–Statistically inferred strategies
•Regression techniques
•EuroQol, Quality of Well-Being Scale (QWB)
–Explicitly decomposed methods
•Multi Attribute Utility Theory (MAUT)
•Health Utility Index (HUI)
Statistically inferredstrategies
•Value a sample of states empirically
•Extrapolation
–Statistical methods, like linear regression
–11111 = 1.00
–11113 = .70
–11112 = ?
Statistically inferredstrategies
•EuroQol
–EQ-5D: 5 dimensions of health
–245 health states
•Quality of Well-Being scale (QWB)
–4 dimensions of health
–2200 health states plus 22 additional symptoms
•SF-36
–SF-6D: 6 dimensions of health
–18.000 health states
Explicitly Decomposed Methods
•Value dimensions separately
–Between the dimensions
–What is the relative value of:
•Mobility…... 20%
•Mood……….. 15%
•Self care.… .24%
•Value the levels
–Within the dimensions
–What is the relative value of
•Some problems with walking…..80%
•Much problems with walking……50%
•Unable to walk………..……………….10%
•21111 = 1 - (0.20 x (1.00 - 0.80)) = 0.96
Explicitly DecomposedMethods
•Combine values of dimensions and levels withspecific assumptions
–Multi Attribute Utility Theory (MAUT)
•Mutual utility independence
•Structural independence
Explicitly DecomposedMethods
•Health Utilities Index (Mark 2 & 3)
–Torrance at McMaster
–8 dimensions
–Mark 2: 24.000 health states
–Mark 3: 972.000 health states
•The 15-D
–Sintonen H.
–15 dimensions
–3,052,000,000 health states (3 billion)
More health states, highersensitivity ? (1)
•EuroQol criticised for low sensitivity
–Low number of dimensions
•Development of EQ-5D plus cognitive dimension
–Low number of levels (3)
•Gab between best and in-between level
More health states, highersensitivity ? (2)
•Little published evidence
–Sensitivity EQ-5D < SF-36
•Compared as profile, not as utility measure
–Sensitivity EQ-5D HUI
•Sensitivity the number of health states
–How well maps the classification system theillness?
–How valid is the modelling?
–How valid is the valuation?
More health states, moreassumptions
•General public values at the most 50 states
•The ratios empirical (50) versus extrapolated
–Rosser & Kind1:1
–EuroQol1:5
–QWB1:44
–SF-361:180
–HUI (Mark III)1:19,400
–15D1:610,000,000
•What is the critical ratio for a valid validation?
Conflicting evidence sensitivity SF-36
Liver transplantation, Longworth et al., 2001
SF-36 as utility instrument
•Transformed into SF6D
•SG
•N = 610
•Inconsistencies in model
–18.000 health states
–regression technique stressed to the edge
•Floor effect in SF6D
Collapsing levels SF-6D
•Many levels are taken together
–If PF=2decrement: - 0.056
–If PF=3decrement: - 0.056
–If RL=2decrement: - 0.073
–If RL=3decrement: - 0.073
–If RL=4decrement: - 0.073
SF-6D loses a lot of levels
•Levels clas.system and actual levels
–PF6 5
–RL 42
–SF 55
–PN 65
–MH 54
–VI 53
•Levels in clas. system: 18.000
–6x4x5x6x5x5
•Actual levels: 480
–5x2x5x5x4x3
Some levels in the SF-6D do notwork…
EQ-5D
•Strong punts
–Very sensitive in the low
–Measures subjective burden (inside the skin)
–Low administrative burden
–Many translations
–Cheap
–Most used QALY questionnaire
–Most international validations
•Weak points
–Only there levels per dimensions
–Insensitive in the high regions
HUI
•Strong punts
–Sensitive
–Measures objective burden (outside the skin)
–Well developed proxy versions
–Well developed child versions
•Weak points
–Expensive
–Only a few valuation studies
SF-6D
•Strong punts
–Probably sensitive in the high regions
–Often already include in trials (SF-36)
–Many translations
•Weak points
–Insensitive in the low regions
–Only a few validation study
–Might be expensive
Conclusions
•More states better sensitivity
•The three leading questionnaires
–have different strong and weak points