quality of life assessment introduction jan j. v. busschbach, ph.d. –jannetvb/busschbach...
TRANSCRIPT
![Page 1: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/1.jpg)
Quality of life Assessmentintroduction
• Jan J. v. Busschbach, Ph.D.– www.xs4all.nl/~jannetvb/busschbach
• Department of Medical Psychology and Psychotherapy, Erasmus MC
– +31 10 4087807
• Psychotherapeutic Centrum ‘De Viersprong’, Halsteren
– +31 164 632200
![Page 2: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/2.jpg)
Quality of life
• “…. Health is physical, mental and social well-being and not merely the absence of disease or infirmity...”
– World Health Organization, 1947
• Extending health to well-being: Quality of life
• What is the definition of quality of life?
![Page 3: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/3.jpg)
Definitions of Quality of Life
• Quality of life is the degree of need and satisfaction within the physical, psychological, social, activity, material and structural area (Hörnquist, 1982).
• Quality of life is the subjective evaluation of good and satisfactory character of life as a whole (De Haes, 1988).
• Health related quality of life is the subjective experiences or preferences expressed by an individual, or members of a particular group of persons, in relation to specified aspects of health status that are meaningful, in definable ways, for that individual or group (Till, 1992).
• Quality of life is a state of well-being which is a composite of two components: 1) the ability to perform everyday activities which reflects physical psychological, and social well-being and 2) patient satisfaction with levels of functioning and the control of disease and/or treatment related symptoms (Gotay et al., 1992).
• An individual’s perception of their position in life in the context of the culture and values systems in which they live and in relation to their goals, expectations, standards and concerns (WHO Quality of life Groups, 1993).
![Page 4: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/4.jpg)
No clear definition because:
• Many possible definitions– Multi-dimensionally
– Subjective
– Related to society
• Researchers are free to choose – The notion of measuring the quality of life could include the
measurement of practically anything of interest to anybody. And, no doubt, everybody could find arguments supporting the selection of whichever set of indicators to be his choice (Andrews & Withy, 1976, page 6)
![Page 5: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/5.jpg)
No clear definition because:
• Different origins of research– Clinical decision making: Does the patient benefit from the
treatment?
– Epidemiology (public health): what is the morbidity of the population?
– Health economics: Is it worth the money?
![Page 6: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/6.jpg)
Common items in definitions:
• It is not the doctor who reports
• Quality of life is subjective….– “Given its inherently subjective nature, consensus was quickly
reached that quality of life ratings should, whenever possible, be elicited directly from patients themselves. “ (Aaronson, in B Spilker (Ed): Quality of life and Pharmacoeconomics in Clinical Trails, 1996, page 180)
– Reports between proxies and patients vary.
![Page 7: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/7.jpg)
Common items in definitions:
• Health related
• Multidimensional – Physical, psychological, social
• Questionnaires– Standardize questions and response
» Reproducible results: sciences
» Quantify subjectivity
• Operational defined– Like IQ and temperature.
![Page 8: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/8.jpg)
How to measure quality of life form a clinical point of view?
• Choose items– Are you able to walk one kilometer ?
– Do you feel depressed ?
• Choose response mode– Binary yes / no
– Multiple (Likert) yes / at bid / hardly / no
– Continuous (Visual Analogue Scale) Always ————X—— Never
• Combine items to dimensions of quality of life– Sum up the items belonging to one dimension
– Rescale sum on a scale from 0 to 100
![Page 9: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/9.jpg)
Quality of life form a clinical point of view: profiles
0
10
20
30
40
50
60
70
80
90
100
Physicalfunctioning
SocialFunctioning
RolePhysical
Roleemotional
Mentalhealth
Vitality Bodily pain GeneralHealth
Dimensions of Qaulity of life
Sco
res
scale
d f
rom
0 t
o 1
00
Hospital pharmacist
General pop.
Hypertention
Diabetes II
Growth hormon def.
Depression
![Page 10: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/10.jpg)
The problem of multidimensionality
• What if outcome conflict– e.g: better mobility, but worse roll emotional
– On has to weight or combine outcomes
• What if some patients dies?– Cancer therapy
» Better quality of life, but higher mortality
– Weight quality of life with mortality
![Page 11: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/11.jpg)
Time Without Symptoms of disease and subjective Toxic effects of treatment
• TWiST– Developed by Gelber (statistician)
• In search for a typical “cancer” problem– Often prolonged life but also a reductions in quality of life
» At the beginning (side effects)
» At the end
– Only count the days without symptoms of disease and subjective toxic effects of the treatment
![Page 12: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/12.jpg)
Time Without Symptoms of disease and subjective Toxic effects of treatment
0
20
40
60
80
100
120
140
160
180
1st Qtr 2nd Qtr 3rd Qtr 4th Qtr
First Year of treatment
Av
era
ge
nu
mb
er
of
TW
iST
's
Drug
Placebo
![Page 13: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/13.jpg)
TWiST ignores differences in quality of life
• TWiST– Healthy = 1
– Sick (dead) = 0
• There is more to life than sick/health– Make scale 0..1
– Quality adjusted TWiST (Q-TWiST)
• Q-TWiST = QALY– Quality Adjusted Life Year
![Page 14: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/14.jpg)
QALY Analysis
• 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”
![Page 15: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/15.jpg)
Which health care program is the most effective?
• A new cancer therapy– Quality of life = 0.7
– 1.5 year survival
– QALY = Y x V(Q) – 1.5 x 0.7 – 1.05 QALY
• The standard therapy– Quality of life = 0.8
– 1.0 year survival
– QALY = Y x V(Q) – 1.0 x 0.8 – 0.8 QALY
![Page 16: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/16.jpg)
How to measure QoL for the calculation of QALYs?
• One needs a uni-dimensional value of quality of life
– Like the IQ-test measures intelligence
• Ratio or interval scale– Difference between 0 and .8 must be 8 time higher than .1
• Four popular methods have these pretensions
– Visual Analog Scale
– Time Trade-Off
– Standard Gamble
– Person trade-off
![Page 17: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/17.jpg)
Value a health state
• You are in a wheelchair
• No pain or discomfort
• No psychosocial problems
![Page 18: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/18.jpg)
Visual Analogue Scale
• VAS– Also called category scaling
• From psychological research
• “How is your quality of life today ?”
• “X” marks the spot– Response in centimeters
– Rescale to [0..1]
• Different anchor point possible:– Normal health (1.0) versus dead (0.0)
– Best imaginable health versusworse imaginable health
Dead
Normal health
X
![Page 19: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/19.jpg)
Time Trade-Off
• TTO
• Wheelchair– With a life expectancy: 50 years
• How many years would you trade-off for a cure?
– Max. trade-off is 10 years
• QALY(wheel) = QALY(healthy)– Y * V(wheel) = Y * V(healthy)
– 50 V(wheel) = 40 * 1
• V(wheel) = .8
![Page 20: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/20.jpg)
Standard Gamble
• SG
• Wheelchair
• Life expectancy is not important here
• How much are risk on death are you prepared to take for a cure?
– Max. risk is 20%
– 100% life on wheels = (100%-20%) life on feet
– V(Wheels) = 80% or .8
![Page 21: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/21.jpg)
Values differN = 103 students
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
EQ-5D health states
Uti
liti
es
SG
TTOVAS
![Page 22: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/22.jpg)
Comparisons of valuation methods (1)
• Visual analogue scale– Easy
– No trade-off: no relation to QALY
» No interval proportions
– Massive evidence
» Much from other social sciences
• Standard Gamble / Time trade-Off– Less easy
– Trade-off: clear relation to QALY
» Interval proportions
– Much evidence
» Especially in health economics
![Page 23: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/23.jpg)
Comparisons of valuation methods (2)
• Person Trade-Off– Difficult
– Trade-off: unclear relation QALY
» Include egalitarian aspects of health care
» Unclear interval proportions
– Very little evidence
– Controversial results
» Extreme value compression
![Page 24: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/24.jpg)
Patient values seem high
• Stensman– Scan J Rehab Med
1985;17:87-99.
• Scores on a visual analogue scale
– 36 subjects in a wheelchair
– 36 normal matched controls
• Mean score– Wheelchair: 8.0
– Controls: 8.3
![Page 25: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/25.jpg)
0.4
0.6
0.8
1
Pre-test Post-test
Qo
L v
alu
e
General public
Patient
" Thentest "
Response shift
![Page 26: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/26.jpg)
Interpretation response shift
• Thentest = true value– Saves trouble of pre-test
– But….is the post-test still true?
» Should we do a thenposttest as well?
– Does this say that patient can not judge their own health?
![Page 27: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/27.jpg)
Which patient should we ask?
• Those with experience?
– Who are they?
• The amount of experience
– Length of experience
– Time since experience
– Strength of relation with patient
No experience
Family
Friends
SelfNow recently distant never
Long
Some time
No time at all
All current patients
![Page 28: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/28.jpg)
Quality of life in patients
• When should we ask?– Which patients should we ask?
• Response shift– Is a low quality of life a sign of
» a low physical functioning?
» an absence of the response shift?
![Page 29: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/29.jpg)
The incomprehensible patient
• Keeps on coming back to the clinic
• Modifies social environment
• Passive in own goals
• Angry, depressed, suspicious
• Low quality of life
![Page 30: Quality of life Assessment introduction Jan J. v. Busschbach, Ph.D. –jannetvb/busschbach Department of Medical Psychology and Psychotherapy,](https://reader030.vdocuments.us/reader030/viewer/2022032523/56649d8c5503460f94a7480e/html5/thumbnails/30.jpg)
Adaptation and quality of life
• A low quality of life sign of low adaptation
• Increase adoption will increase quality of life
• A starting point for psychological therapy– A low quality of life
– Malfunctioning of adaptation
– Wrong coping strategy
» Behavioral / peer group therapy
– Personality disorder
» More invasive therapy