Older age, female sex, fire accidents, natural disasters, motor vehicle accidents, assaults, self-injuries, number of hospital inquiries ≥ 4, and the COVID-19 pandemic influenced prolonged OSTs among patients with minor diseases or injuries. To improve community EMS, we should reconsider how to intervene with potentially modifiable factors, such as EMS personnel performance, the impact of the presence of allied services, hospital patient acceptance systems, and cooperation between general emergency and psychiatric hospitals.