To measure optimism, the LOT-R was used in this study [22 (link)]. The LOT-R consisted of 10 items, consisting of 3 generalized positive expectations, 3 negative expectations, and 4 ambiguous questions. Ambiguous questions were inserted to prevent the examination’s intention from being understood. Negative expectation items were reversely scored, and ambiguous items were excluded from scoring. Each item was rated on a 5-point scale (1=not at all, 5=very much), and a higher score indicated higher optimism. The Korean version used in this study showed acceptable reliability with Cronbach’s alpha 0.75 in the previous study [23 ].