Psychometric properties and heritability of a new online test for musicality, the Swedish Musical Discrimination Test

Abstract

We examine, in 6881 twin individuals, the psychometric properties of a new test (the Swedish Musical Discrimination Test, SMDT) that was developed to tap auditory discrimination of musical stimuli. The SMDT consists of three subtests measuring discrimination of melodies, rhythms, and single pitches, respectively. Mean test taking times for the subtests were 3.0–4.6min. Reliability and internal consistency were good with Cronbach’s alpha values and Spearman–Brown split-half reliabilities between .79 and .89. Subtests correlated positively (r values .27–.41). Criterion validity was demonstrated in three ways: individuals that had played a musical instrument scored higher than individuals that had not (Cohen’s d .38–.63); individuals that had taken music lessons scored higher than individuals that had not (Cohen’s d .35–.60); finally, total hours of musical training and SMDT scores correlated (r values .14–.28) among those participants that had played an instrument. Lastly, twin modelling revealed moderate heritability estimates for the three sub-scales. We conclude that the SMDT has good psychometric characteristics, short test taking time, and may serve as a useful complement to existing tests of musical ability.