HEALTH ECONOMICS
Sponsored by a Grant TÁMOP-4.1.2-08/2/A/KMR-2009-0041 Course Material Developed by Department of Economics,
Faculty of Social Sciences, Eötvös Loránd University Budapest (ELTE) Department of Economics, Eötvös Loránd University Budapest
Institute of Economics, Hungarian Academy of Sciences Balassi Kiadó, Budapest
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Authors: Éva Orosz, Zoltán Kaló and Balázs Nagy Supervised by Éva Orosz
June 2011
Week 9
Measurement of health gain in economic evaluations
Authors: Zoltán Kaló and Balázs Nagy Supervised by Éva Orosz
Meaningful health benefit for patients
• Life years (not only 5 year survival)
• Quality of life
• Combinations
– QALY (Quality Adjusted Life Years) – HYE (Healthy Year Equivalents) – DALY (Disablity Adjusted Life Years)
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Hormone replacement therapy Women Health Initative study
Outcome oestrogen + progesterin (n = 8506)
placebo (n = 8102)
Relative risk
mean follow-up (month) 62.2 (16.1%) 61.2 (15.0%)
hip fracture 44 (0.10%) 62 (0.15%) 0.66
vertebral fracture 41 (0.09%) 60 (0.15%) 0.66
coronary disease 164 (0.37%) 122 (0.30%) 1.29
stroke 127 (0.29%) 85 (0.21%) 1.41
venous thromboembolic disease
151 (0.34%) 67 (0.16%) 2.11
deep vein thrombosis 115 (0.26%) 52 (0.13%) 2.07
pulmonary embolism 70 (0.16%) 31 (0.08%) 2.13
total cardiovascular disease
694 (1.57%) 546 (1.32%) 1.22
invasive breast cancer 166 (0.38%) 124 (0.30%) 1.26
endometrium cancer 22 (0.05%) 25 (0.06%) 0.83
colon and rectal cancer 45 (0.10%) 67 (0.16%) 0.63
cancer total 502 (1.14%) 458 (1.11%) 1.03
Chlebowski RT et al: JAMA, 289, 24, 2003, 3243-53
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Hormon replacement: WHI results reflect previous study results?
Hormone replacement: QoL gain compensate for increased risks?
Combined hormone replacement:
• No significant impact on: general health, vitality, mental health, depressive symptoms, sexual satisfaction
• Statistically significant, but clinically not relevant improvement after 1 year: sleeping disorder (0.4 points out of 20 points), physical functioning (0.8 out of 100 points), pain (1.9 out of 100 points)
• After 3 year no significant improvement in any parameter.
Hays J et al. N Engl J Med, 348, 19, 2003, 1839-54.
Col N et al: Arch Intern Med. 2004;164:1634-1640.
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“We should set the highest value not on living but on living well.”
Socrates
Determinants of QoL
Health related quality of life
• Exclude factors not influenced by health care services and providers
• Solution: validated and standardized QoL instruments in randomized controlled trials
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Examples of impairments, disabilities and handicaps
Attributes of HRQoL
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Assessment of QoL instruments (I)
• Validity: ability to distinguish QoL of patients with different levels of health status
• Interpretability: measurement expresses small, moderate, serious change or improvement in QoL
Assessment of QoL instruments (II)
• Reliability / reproducability: same results for repeated measurement
• Sensitivity / Responsiveness: ability to detect small but clinically significant changes in QoL
Validation phases
Outlook (qualitative)
• face validity – language
– outlook, letter size – simplicity
• content validity
Content (quantitative)
• criteria validity
• construct validity – convergence – divergence
• reliability
– internal consistency – reproducability
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Local adaptation of QoL instruments
• validity of different language versions has to be equal with the validity of the original version
• mirror translation is not recommended
Attributes of health state classification
system
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Classification of QoL instruments
QALY measurement
• QALYs - duration of time weighted by a health status preference score, discounted
• “The policy objective underlying the QALY literature is the maximization of the community’s health. An individual’s “health” is measured in terms of QALYs and the community’s health is measured as the sum of QALYs” Source: Wagstaff A, JHE, 1991
General Disease specific
Index • Rosser-Kind matrix
• Quality of Well-being
• EQ-5D
• Arthritis Impact Measurement Scale
• General Health Questionnaire Profil • Nottingham Health
Profile
• SF-36 (Short Form 36)
• Sickness Impact Profile
• Kidney Disease Questionnaire
• RAQoL
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QALY gain by oncology treatment
Why measuring QALYs?
• main attributes of efficacy could be different for assessed health technologies, therefore comparison is difficult
• outcome attributes of a single health technology can be different, therefore overall assessment of health gain is difficult:
– life years gain,
– long-term QoL benefit, – serious adverse events – short term adverse events, – short term QoL
0 0,2 0,4 0,6 0,8 1
life years
utility weights
