Maximal endurable time states and the standard gamble: more preference reversals

Area of Science:

• Health Economics
• Decision Analysis
• Psychometrics

Background:

• The time trade-off (TTO) method is known to be sensitive to maximal endurable time preferences, exhibiting preference reversals.
• The sensitivity of the standard gamble (SG) method to maximal endurable time preferences has not been previously investigated.

Purpose of the Study:

• To investigate whether preference reversals occur for the standard gamble (SG) method.
• To compare the sensitivity of the SG method to maximal endurable time preferences with that of the TTO method.

Main Methods:

• Fifty-nine participants evaluated several migraine health states.
• Participants indicated preferences for living 10 or 20 years in a selected migraine state, identifying maximal endurable time preferences.
• Two probability equivalent gambles were constructed for the 10- and 20-year durations of the selected migraine state.
• Preference reversals were identified when a gamble equivalent to a longer duration was preferred over a gamble equivalent to a shorter duration.

Main Results:

• Out of 59 respondents, 48 (81%) exhibited maximal endurable time preferences.
• Among those with maximal endurable time preferences, 34 (71%) demonstrated preference reversals.
• This reversal rate was significantly higher than chance (50%, P = 0.004), indicating reliable occurrence.

Conclusions:

• The standard gamble (SG) method shows a similar rate of preference reversals as the time trade-off (TTO) method.
• Both the TTO and SG methods present challenges for accurate utility measurement of poor health states.