The COVID-19 pandemic together with the strategies that are applied to control it is
generating high morbidity and mortality worldwide. Its impact on health systems is worrisome,
affecting all the population, even those who are not infected or at risk.

The indirect impact of the COVID-19 pandemic on the access to the medical care of patients on
the waiting list for organ transplantation might be multifactorial, including the need to
relocate health-related resources (medical personnel, supplies, critical care unit beds,
etc), the risk of COVID-19 transmission among donors or patients on the waiting list, and
also after transplantation. Additionally, the pandemic reduces significantly the donor pool.

We consider that it is important to assess the impact that the pandemic has in particular
individual populations, such as in patients requiring a liver transplant. Along with the
lockdown, the rate of organ donation has dropped, and liver transplant programs across the
world have reduced or suspended their activity. Unfortunately, this is invariably associated
with an increase in mortality on the waiting list.

Knowing the impact of the pandemic on patients who require a liver transplant will provide
tools to understand and plan the health resources related to the care of these patients, not
only at present but also in the following years.

The primary objectives of the study will be

To Compare the following outcomes in patients requiring liver transplantation during the
epidemiological weeks of COVID-19 pandemic in Argentina and the same weeks of 2019 according
to national data registry of procurement and transplantation:

1. Number of patients registered on the liver transplant waiting list

2. Number of deaths on the liver transplant waiting list

3. Number of liver transplants

For this purpose, we will carry out a time series analyses using the national data registry
of procurement and transplantation database. The effect of both periods will be analysed as
time interrupted series, which is a quasi-experimental design. The following two periods will
be compared as segments of the interrupted time series:

- Baseline period (Period not exposed to the pandemic represented by the same
epidemiological weeks of 2019 )

- Pandemic period COVID-19. (Period between the epidemiological weeks of 2020 affected by
the pandemic declared by the WHO from 11/March/2020)

The unit of analysis will be the epidemiological weeks, and the study population will be all
Argentinian over 17 years of age. Regarding patients who require liver transplantation, those
who registered for isolated liver transplantation in the National Procurement and Transplant
Institute will be included.

A Poisson regression model will be used to assess the association between the period and the
incidence of the events of interest. ARIMA models will be used following the 4 steps proposed
by Box and Jenkings