Correction: COVID-19 Discourse on Twitter in Four Asian Countries: Case Study of Risk Communication - Park, Sungkyu; Han, Sungwon; Kim, Jeongwook; Molaie, Mir Majid; Vu, Hoang Dieu; Singh, Karandeep; Han, Jiyoung; Lee, Wonjae; Cha, Meeyoung (JMIR Publications, 2021)