Entity theory of emotion was associated with more daily negative affect during quarantine: Evidence from a 14-day diary study among healthy young adults.

During the COVID-19 pandemic, quarantine has been implemented as a physical distancing measure to reduce the risk of transmission. However, no studies have examined the relationship between quarantine and daily affective experiences. Few studies have examined the individual-level factors that may alleviate or strengthen the negative impact of quarantine on daily affective experiences. To this end, we conducted a diary study by comparing the affective experiences of people in quarantine with those of people not subject to quarantine. There were 201 participants in the study. After the pretest collecting responses on demographic information and entity theory of emotion, the participants completed a daily questionnaire measuring their daily positive and negative affect for 14 consecutive days. The results of hierarchical linear modeling showed that the participants in the quarantine condition reported less daily positive affect than those in the social interaction condition. We found that when the participants under quarantine believed more strongly that their emotions could not be changed, they reported a higher level of daily negative affect. These findings demonstrate the role of entity theory of emotion in understanding daily negative affect during quarantine.