an extended cox proportional hazards model and it's application in covid-19 patients

The cox proportional hazards (cph) model is one of the most popularregression techniques in survival analysis, which is used to relate several risk factorsor exposures, considered simultaneously, to survival time. an essential assumptionin this model is that the hazard ratio over time must be constant. there are somesolutions when this assumption are not met. in this paper, we proposed an extendedcph model and applied it to medical record data of some covid-19 patients that ishospitalized from 2019 to 2021. the results indicate that there is a linear relationshipbetween therapy via three drugs including azithromycin, favipiravir, and remdesivirand survival time of hospitalized patients. this method can be used for study thetreatment eect of other drugs.