Conventional and Kampo medicine in the treatment of mild to moderate COVID-19: A multicenter, retrospective observational study protocol by the Integrative Management in Japan for Epidemic Disease (IMJEDI study-Observation)

Aim: We present the study protocol of a multicenter, retrospective observational study that aims to investigate the efficacy of the actual treatment (the efficacy of conventional and Kampo medicines) of patients with mild to moderate or suspected coronavirus disease (COVID-19). Methods: This study is designed as a multicenter, retrospective observational study. Outpatients and inpatients will be recruited from Japanese hospitals. The inclusion criteria are as follows: having or suspected to have COVID-19, mild to moderate COVID-19, symptomatic, ≥20 years of age, male or female, able to communicate in Japanese, and treated with conventional and Kampo medicine. The exclusion criteria are: unable to provide informed consent due to dementia, psychosis, or psychiatric symptoms, severe COVID-19, or determined unsuitable for this study. The sample size is set at 1000, as this number of people can be treated at the collaborating medical institutions during the study period. Results: The main outcome is the number of days without fever, with a body temperature of less than 37°C. The secondary outcome is set at common cold-like symptoms other than fever (fatigue, cough, shortness of breath, sputum, diarrhea) and severity of illness and hospitalization up to 14 days after the visit. Trial registration: The trial was registered in the University Hospital Medical Information Network (Reservation No. UMIN000041301) on August 4, 2020. Conclusion: Our study will explore the contribution of conventional and Kampo medicine in the treatment of patients with mild and moderate COVID-19.