Valuing health at the end of life an examination of framing effects and study design considerations
1. VALUING HEALTH AT THE END OF LIFE
AN EXAMINATION OF FRAMING EFFECTS AND
STUDY DESIGN CONSIDERATIONS
Koonal Shah (Office of Health Economics, UK)
Aki Tsuchiya (University of Sheffield, UK); Allan Wailoo (University of Sheffield, UK)
For further information, contact Koonal Shah – kshah@ohe.org
METHODS
• Preferences were elicited from a representative sample of the UK general public using an online survey (n=2401).
• Respondents were randomly allocated to one of six survey versions (Table 1).
• Respondents were asked which of two patients they would prefer to treat, assuming only one could be treated.
This study was funded by the National Institute for Health and Care Excellence via its Decision Support Unit.
The views (and any errors or omissions) expressed are of the authors only.
CONCLUSIONS
• The overall results were not consistent with an end of life premium.
• Respondents’ choices were found to be sensitive to the inclusion of indifference
options and (to a lesser extent) visual aids. However, in no arm did a majority of
respondents choose to prioritise the treatment of the end of life patient.
• Researchers should seek to control for framing effects when examining people’s
health care priority setting preferences.
PRIMARY OBJECTIVE
• To assess whether any observed preferences regarding an end of life premium are affected by framing effects
RESULTS
Visual aid arm No visual aid arm
Forced choice arm Version 1 Version 4
Indifference arm Indifference option 1 Version 2 Version 5
Indifference option 2 Version 3 Version 6
Table 1. Study arms and survey versions
Indifference option 1: I have no preference (I do not mind which patient is treated)
Indifference option 2: Both patients should have an equal chance of being treated (tossing a coin
would be a fair way to make the choice)
Figure 1. Example of visual aid (versions 1-3 only)
Scenario Forced
choice
Indiff. 1 Indiff. 2
No visual
aid
Visual Aid
S1
End of life patient (A) vs. non-end
of life patient (B) A I I I B
S2
Older end of life patient (A) vs.
younger non-end of life patient (B) B B B B B
S3
End of life patient with more time
with knowledge (A) vs. non-end of
life patient with less time with
knowledge (B)
B I I B I
S4
Quality of life improvement for end
of life patient (A) vs. life extension
for end of life patient (B)
A A I A A
S5
Quality of life improvement for end
of life patient (A) vs. life extension
for non-end of life patient (B)
A A A A A
S6
Quality of life improvement at end
of normal life expectancy (A) vs.
life extension at end of normal life
expectancy (B)
A I I A A
S7
Smaller life extension for end of
life patient (A) vs. larger life
extension for end of life patient (B)
B B I B B
• In S1, the modal
choice in the forced
choice arm was to
treat the end of life
patient, whereas for
respondents in the
indifference arm
this was the least
common choice.
• Significant
association
observed between
availability of an
indifference option
and propensity to
choose to treat the
end of life patient
(p<0.01).
• Across all
scenarios,
indifference was
expressed more
frequently by
respondents in
indifference option
2 arm (p<0.01).
Table 2. Modal choice in each scenario/arm
• Impact of including a visual aim varied across scenarios. In the three arms in which one of
the options involved a quality of life-improving treatment, respondents in the visual aid arm
were more likely to choose the other (life-extending) option. In most cases, however, the
association between response pattern and inclusion of a visual aid was not significant.
Note: This poster presents selected
elements of a broader methodological
study. Other topics examined included:
whether respondents’ end of life
preferences are affected by whether
the preferences are elicited from an
individual or a social decision maker
perspective; and an examination of the
consistency of respondents’ views
using two different approaches (choice
tasks vs. attitudinal questions with
Likert item responses).