1. Reduced In-Person and increased telehealth outpatient visits during the COVID-19 pandemic;Baum;Ann Intern Med,2021
2. Mehrotra A , Chernew M , Linetsky D , et al . The impact of the COVID-19 pandemic on outpatient visits: practices are adapting to the new normal. Commonwealth fund, 2021. Available: https://www.commonwealthfund.org/publications/2020/jun/impact-covid-19-pandemic-outpatient-visits-practices-adapting-new-normal
3. Trends in outpatient care delivery and telemedicine during the COVID-19 pandemic in the US;Patel;JAMA Intern Med,2021
4. Ministry of Health, Labor and Welfare . Hospital report, 2021. Available: https://www.mhlw.go.jp/toukei/saikin/hw/byouin/m19/dl/1905kekka.pdf
5. Ministry of Health, Labor and Welfare . Hospital report, 2021. Available: https://www.mhlw.go.jp/toukei/saikin/hw/byouin/m20/dl/2005kekka.pdf