Brief Assessments of Delay Discounting: Two-Amount Monetary Choice and Delayed Losses Questionnaires

The Monetary Choice Questionnaire (Kirby et al., Journal of Experimental Psychology: General, 128, 78–87, 1999) and the Delayed Losses Questionnaire (Myerson et al., Journal of Behavioral Decision Making, 30, 359–372, 2017) are two reliable instruments for measuring the discounting of delayed gains and delayed losses, respectively. The present study examined whether shortened versions, which did not include the 9 medium-sized amount questions, preserved the psychometric properties of the original three-amount, 27-question versions. Analyses revealed high internal consistency (α >.88) and strong correlations of discounting measures between the two delayed amounts (r >.69) for each brief version. Moreover, the brief versions replicated key findings from the original questionnaires: Group choice proportions changed nonlinearly with delay, and there was a clear amount effect with delayed gains, but far smaller effect of amount with delayed losses. Taken together, these results suggest that the brief version of the Monetary Choice Questionnaire and the Delayed Losses Questionnaire, in which the medium-sized amount is eliminated, are psychometrically sound alternatives to the original questionnaires, preserving comparable reliability and validity while reducing administration time by a third, an important consideration for online studies in which additional tasks or variables are being used or evaluated.