Design: A multicenter observational, prospective cohort study

Setting: Intensive Care Units

Subjects: Adult Critical patients admitted to ICU with severe community-acquired
pneumonia due to confirmed SARS CoV-2 infection (COVID-19).

Data Collection and Validation Data was obtained from a voluntary registry created by
Spanish Society of Intensive Care Medicine-SEMICYUC. All consecutive cases admitted to
the ICU were collected.

There were no patients excluded from the analysis that was enrolled to participating ICU
and met criteria.

Data were collected using a paper CRF (case Report Form). CRF collect and record all
protocol-required information, which is transcribed from patient source documents, such
as hospital records and laboratory reports during the patient's participation in the
study. Before being sent to the National Study Coordinator (AR) this data was
de-identified (not traceable to the patient) by removing the patient's name, medical
record number, etc., and giving the patient a unique study number. We implemented a
double data entry model for potential errors in real-time. Data was entered twice by two
different Data Entry personnel based on the same set of data collected in the paper CRFs.
All data were reviewed, and values that appeared incongruent or out of range were
manually validated by confirming the accuracy of the data with the Study Coordinator
(AR). The database was validated and cleaned before the statistical analysis and the
study database was locked to prevent any further changes, and to ensure data consistency
and integrity for the statistical reporting and analysis.

Sample size calculation:

No statistical sample size calculation was performed a priori, and sample size was equal
to the number of patients admitted to the participant's ICUs with confirmed COVID-19
during the study period.