Psychometric Study of Two Decision-Making Measures: The Melbourne Decision-Making Questionnaire versus the General Decision-Making Style Questionnaire

This study compares the Melbourne Decision-Making Questionnaire (MDMQ) and the General Decision-Making Style questionnaire (GDMS), two of the most widely used decision-making questionnaires in the literature, in a large age- and sex-weighted general population sample of 714 men (45.7%) and 848 women (54.3%) between 18 and 90 years old. The objective was to evaluate the convergent and construct validity between several aspects of these decision-making style questionnaires. The results indicate that the two questionnaires replicate the factorial structure of four and five factors reported in the original studies, respectively, through exploratory and confirmatory procedures in our cross-cultural context. The domains of both questionnaires that represent a strong or large correlation are Vigilance with Rational (0.50), and Hypervigilance, Buck-passing, and Procrastination with Avoidant (0.45, 0.52, and 0.60). A Structural Equations Model (SEM) between both questionnaires indicates that both latent factors formed by the domains of the MDMQ and the GDMS obtain a correlation of 0.96. It is concluded that the two questionnaires measure similar aspects of the decision-making construct.