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EQ-5D, HUI and SF-36. Of the shelf instruments…. Direct valuation. …or use validated questionnaires. 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
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EQ-5D, HUI and SF-36 Of the shelf instruments….
…or use validated questionnaires 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 or leisure 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
The Rosser & Kind index • One of the oldest valuation • 1978: Magnitude estimation • Magnitude estimation PTO • N = 70: Doctors, nurses, patients and general public • 1982: Transformation to “utilities” • 1985: High impact article • Williams A. For Debate... Economics of Coronary Artery Bypass Grafting. British Medical Journal 291: 326-28, 1985. • Survey at the celebration of 25 years of health economics: chosen most influential article on health economics
More health states • Criticism on the Rosser & Kind index • Sensitivity (only 30 health states) • The unclear meaning of “distress” • The compression of states in the high values • The involvement of medical personnel • New initiatives • Higher sensitivity (more then 30 states) • More and better defined dimensions • Other valuation techniques • Standard Gamble, Time Trade-Off • Values of the general public
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 states with 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 inferred strategies • Value a sample of states empirically • Extrapolation • Statistical methods, like linear regression • 11111 = 1.00 • 11113 = .70 • 11112 = ?
Statistically inferred strategies • 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%
Explicitly Decomposed Methods • Combine values of dimensions and levels with specific assumptions • Multi Attribute Utility Theory (MAUT) • Mutual utility independence • Structural independence
Explicitly Decomposed Methods • 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)
Exercise EQ-5D: 12311 X X X X X
Converting SF-36 into SF-6D X X X X
More health states, higher sensitivity ? (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, higher sensitivity ? (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 the illness? • How valid is the modelling? • How valid is the valuation?
More health states, more assumptions • General public values at the most 50 states • The ratios empirical (50) versus extrapolated • Rosser & Kind 1:1 • EuroQol 1:5 • QWB 1:44 • SF-36 1:180 • HUI (Mark III) 1:19,400 • 15D 1:610,000,000 • What is the critical ratio for a valid validation?
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
Conflicting evidence sensitivity SF-36 Liver transplantation, Longworth et al., 2001
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
SF-6D • Strong punts • Probably sensitive in the high regions • Often already include in trials (SF-36) • Cheap • Many translations • Weak points • Insensitive in the low regions • Only one validation study • Changed Standard Gamble • Upwards shift of values
Conclusions More states better sensitivity The three leading questionnaires have different strong and weak points