1 Quality of life and Cost-Effectiveness An Interactive Introduction Prof. Jan J. v. Busschbach, Ph.D. Erasmus MC Medical Psychology and Psychotherapy Viersprong Institute for studies on Personality Disorders

I want to live in… Land A  Life expectancy 80  Quality of life 0.8  Cures common diseases Land B  Life expectancy 78.8  Quality of life 0.75  Cures catastrophic diseases 2

I would spend money on…  High incidence  Many patients  High burden  Genetic cause  Effective treatment  Curtain outcome  Low incidence  Limited patients  Low burden  Behavioral cause  Non effective treatment  Uncertain outcome 3

I would spend money on…  Low incidence  Many patients  High burden  Genetic cause  Effective treatment  Curtain outcome  High incidence  Limited patients  Low burden  Behavioral cause  Non effective treatment  Uncertain outcome 4

5 New cancer therapy SymptomsDrug XDrug Y Survival days Days sick of chemotherapy Days sick of disease TWiST

6 Time Without Symptoms of disease and subjective Toxic effects of treatment: TWiST  Richard Gelber  statistician  Count …  Days not sick from treatment  Days not sick from disease 6

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8 Fit new therapy in fixed budget  50 patients each year (per hospital)  Drug x: 50 x euro = euro  Drug y: 50 x euro = euro  Drug budget for x or y = euro  Number of patient Drug x: euro / = 28.5 patients Drug y: euro / = 25.0 patients  Survival in days Drug x: 28.5 patients x 300 days = days Drug y: 25.0 patients x 400 days = days  Survival in TWiST Drug x: 28.5 patients x 190 TWiST = days Drug y: 25.0 patients x 220 TWiST = days

9 TWiST: ignores differences in quality of life  TWiST  Healthy = 1  Sick (dead) = 0  Q-TWiST Quality of life adjusted TWiST  Make intermediate values 1.0; 0.75; 0.50; 0.25; 0.00  How to scale quality of life? Quality of life 1.0

10 Uni-dimensional scale  Quality of life  World Health Organization, 1947  “…. Health is physical, mental and social well-being and not merely the absence of disease or infirmity...”  But we need a uni-dimensional scale  Like temperature  IQ  Depression scale  School grad  So we need a overall judgment…

Generic QoL Questions (SF-36) 11

Complex interpretation 12

Weighted index 13

14 Visual Analogue Scale  Does the scale fit Q-TWIST?  Is 2 days 0.5 Q = 1 day 1.0 Q ? 14 Dead Normal health X ?=?=

Interval / Ratio scale  Ratio or interval scale  Difference 0.00 and 0.80 must be 8 time higher than 0.10  Uncommon in psychology 15

16 Time Trade-Off  Wheelchair  With a life expectancy: 50 years  How many years would you trade-off for a cure?  Max. trade-off: 10 years  QALY(wheel) = QALY(healthy)  Y * V(wheel) = Y * V(healthy)  50 V(wheel) = 40 * 1.00  V(wheel) =

17  Example  Blindness  Time trade-off value is 0.5  Life span = 80 years  0.5 x 80 = 40 QALYs Quality Adjusted Life Years (QALY) X Life years x 80 = 40 QALYs

18 QALY  Count life years  Value (V) quality of life (Q)  V(Q) = [0..1] 1 = Healthy 0 = Dead  One dimension  Adjusted life years (Y) for value quality of life  QALY = Y * V(Q) Y: numbers of life years Q: health state V(Q): the value of health state Q  Also called “utility analysis”

19 Q-TWiST = QALY  Several initiatives early seventies  Epidemiologist and health economists  Part of QALY concept  Quality Adjusted Life Years  QALY = Q-TWiST 19

20 Area under the curve

21  A new wheelchair for elderly (iBOT)  Special post natal care Which health care program is the most cost-effective?

SegwayDean Kamen

23  A new wheelchair for elderly (iBOT)  Increases quality of life = 0.1  10 years benefit  Extra costs: $ 3,000 per life year  QALY = Y x V(Q) = 10 x 0.1 = 1 QALY  Costs are 10 x $3,000 = $30,000  Cost/QALY = 30,000/QALY  Special post natal care  Quality of life = 0.8  35 year  Costs are $250,000  QALY = 35 x 0.8 = 28 QALY  Cost/QALY = 8,929/QALY Which health care program is the most cost-effective?

24 QALY league table

Citations in PubMed

Orphan drugs  Pompe disease  Classical form: infants € /QALY; adults €  New estimates: /QALY;  Low cost effectiveness but…  High burden  Low prevalence  Little own influence on disease  High consensus in the field Coalition patient, industry, doctors and media Low perceived incertainty 26

 …it must be that QALYs are invalid We don’t like the results…

In the past, much criticism Cohen CB. Quality of life and the analogy with the Nazis. Journal of Medicine and Philosophy 8: , 1983.

Criticism remains 29 ….the strictly fascist essence of those QALYs (so-called Quality-Adjusted Life Years)…

30 Chris Murray  WHO avoided QALY  (read: disliked QALYs)  (read disliked health economics)  But WHO in need of a measure of health…  Asked Havard…  “Anything… but QALY”  Chris Murray  School of Public Health  Worked outside  Health economics  Med Decision Making  DALY

31 Burden of disease: QALY lost = DALY (Disability adjusted life year) DALY QALY

ABC Health Egalitarian Concerns: Burden of disease

ABC Levensjaen Costs/QALY as indicator of solidarity € € €

34 Burden as criteria Pronk & Bonsel, Eur J Health Econom 2004, 5:

35 Costs/QALY versus Burden of disease 35 € € € € € 0 Burden of disease X X X X X

36 Dutch Council for Public Health and Health Care (RvZ, 2006) 36

37 QALY debate  Fairness is the issue in the QALY debate  QALY measurement is the straw man  Complex metric discussion  Most debate about quality of life assessment  QALY are seen as unfair  But: QALYs are needed to operationalise fairness 37

38 Conclusion  Quality of life can be measured  Usual multidimensional  Unidimensional: QALYs  QALYs can validly be use in cost effectiveness research  Burden of disease is also a criterion  On need QALYs to measure burden