Comparing mental toughness measures: overlap between the very-short mental toughness questionnaire and the mental toughness index

This study aimed to provide the first comparison of the 4/6C model and unidimensional model of mental toughness (MT) and their respective measures in a mixed athletic sample. A comparison in this way contributes to the ongoing need to clarify how interchangeable prominent and emerging measures of MT are. Following psychometric checks on the Very Short-Mental Toughness Questionnaire (VS-MTQ) and the Mental Toughness Index (MTI), associations between the MT inventories and resilience, grit, and Big Five personality traits, and psychological well-being were examined. A sample of adult athletes (N = 275, female n = 100 M age = 34.46) completed the online survey comprised of the MT instruments and other included constructs. Total scores across the MT measures were moderately correlated (r = .67). Additionally, a confirmatory factor analysis provided mixed support for the structural validity of the MT measures, with the MTI demonstrating more satisfactory fit results. Both MT inventories demonstrated similar associations with the other constructs and factors (e.g., resilience r = .64-.68), with item-level differences providing some nuance to these findings. Although the MTI demonstrated stronger psychometric performance in the current sample, further research is required to determine whether this finding can be replicated and to inform more definitive recommendations regarding MT measure choice.