JMIR Publications

ABSTRACT

We read the study by Jeong et al. on the Effective Control of COVID-19 in South Korea. The paper was written rather well but remained several controversial questions required for discussions, including how (1) to determine the flat infection point(Ipoint for short) at 50 days for South Korea, (2) to ensure other eight counties(eg, United States, Spain, Italy, Japan, Singapore, France, Iran, and the Netherlands) having longer Ipoints than that in South Korea instead of merely observing visual displays, and (3) to confirm no other countries have less Ipoint days that that in South Korea in term of the first 61 days since the 100th confirmed case. We replicated the study using the data-model-fit technique based on item response theory to determine the Ipoint on an ogive curve for each country and found that (1) the Ipoint at 14 days for South Korea, (2) all other eight counties having longer Ipoints(ranged from 33 to 59 days) than South Korea, and (3) 45 countries/regions having Ipoints less than 14 days based on the first 61 days since the 100th confirmed case. The Ipoint to represent the effective control of COVID-19 is an objective and essential measure that can be applied to compare the capability of mitigating COVID-19 among countries/regions.