[1] Kwon R, Rahmati M. Global, regional, and national COVID-19 vaccination rate in 237 countries and territories, March 2022: a systematic analysis for World Health Organization COVID-19 Dashboard, Release 2. Life Cycle, 2022; 2, e15. doi:  10.54724/lc.2022.e15
[2] Ang L, Yim MH, Song E, et al. A nationwide survey on the management of the COVID-19 pandemic and respiratory disease in South Korea. Front Med, 2022; 9, 965651. doi:  10.3389/fmed.2022.965651
[3] Adeloye D, Auta A, Fawibe A, et al. Current prevalence pattern of tobacco smoking in Nigeria: a systematic review and meta-analysis. BMC Public Health, 2019; 19, 1719. doi:  10.1186/s12889-019-8010-8
[4] Koo MJ, Kwon R, Lee SW, et al. National trends in the prevalence of allergic diseases among Korean adolescents before and during COVID-19, 2009-2021: a serial analysis of the national representative study. Allergy, 2023; 78, 1665−70. doi:  10.1111/all.15600
[5] Lee SW. Methods for testing statistical differences between groups in medical research: statistical standard and guideline of Life Cycle Committee. Life Cycle, 2022; 2, e1. doi:  10.54724/lc.2022.e1
[6] Gaffney A, Himmelstein DU, Woolhandler S. Smoking prevalence during the COVID-19 pandemic in the United States. Ann Am Thorac Soc, 2022; 19, 1065−8. doi:  10.1513/AnnalsATS.202110-1184RL
[7] Sun YY, Wang MP, Cheung YTD, et al. Changes in tobacco use at the early stage of the COVID-19 pandemic: results of four cross-sectional surveys in Hong Kong. Tob Induc Dis, 2022; 20, 26.
[8] Gallus S, Stival C, Carreras G, et al. Use of electronic cigarettes and heated tobacco products during the Covid-19 pandemic. Sci Rep, 2022; 12, 702. doi:  10.1038/s41598-021-04438-7
[9] Chen DTH, Kyriakos CN. Cigarette and E-cigarettes dual users, exclusive users and COVID-19: findings from four UK Birth cohort studies. Int J Environ Res Public Health, 2021; 18, 3935. doi:  10.3390/ijerph18083935
[10] Al Ghadban Y, Zgheib N, Romani M, et al. Impact of the COVID-19 pandemic on smoking behavior and beliefs among the American University of Beirut community. Tob Prev Cessation, 2022; 8, 2.