GW HTA lecture 5 Flashcards
Direct valuation measures
- Visual Analogue Scale
- Time Trade Off
- Standard Gamble
Indirect Generic measurment methods
- EQ-5D (3.125 health states)
- SF-6D (18.000 health states)
- HUI 3 (972.000 health states)
EQ-5D 3.125 health states
- Mobility
- self care
- usual activities
- pain discomfort
- anxiety/depression
SF-6D 18.000 health states
- Physical functioning
- Role limitations
- Social functioning
- Mental health
- Bodily pain
- Vitality
HUI3 (health utility index) 972.000 health states
- Vision
- Hearing
- SPeech
- Ambulation
- Dexterity
- Emotion
- Cognition
- Pain
difference in valuation instruments
Questions can differ. For example can all be about mobility. But the answer levels differ. Such as with(out) aids being able to walk.
Number of levels differ
Severity; worst levels or being able or unable (SF6D; mostly highest scores)
Indirect valuation method of SF-6D
Standard Gambling
Modeling technique: Econometric
Indirect valuation method EQ-5D
Time trade-off
Modeling technique: Econometric
Indirect valuation method of HUI3
Value Analogue Scale (SG for few states)
Modeling technique: Multi-attribute utility theory
Why can utility scores differ between indirect and direct valuation?
Because the main difference is the population who values the health states.
Patients will give a higher health state, compared to when you ask someone from the studygroup. For HUI3 biggest difference. 0.2 SD on a scale from 0-1 is a lot.
Difference SG&TTO: 0.02
Difference HUI3-EQ-5D; slide gives
EQ-5D; 0.09
SF-6D 0.05
HUI3 0.18
Who should value health states?
General public;
- in line with societal perspective, also pays for it
- more objective; valuation before own experience (insurance principle)
- Patients adapt to their situation, but for general public health state is often considered worse
Patient;
- only patient know real impact
- Patients can adapt, that changes their value
Values of generic public; generic instrument
- Makes it easier to compare across different diease/health conditions
- Can be applied to any disease
- Often recommended when general public view is used
Values of generic public; disease specific instrument
- more questions about the disease of interst
- better able to measure QoL; assumption needs to be tested
Assessment of performance of instruments
- Reliability
- Validity
- Responsiveness
Reliability
Degree in which the measurment is free from measurement error.
Responsiveness
Abiltity of a measure to detect changes in health
