We thank Dr Lipes for his comments about our systematic review [1].
In his letter, Dr Lipes states that Fig. 2 describes many patients included from Canada but that there was no reference from Canadian studies. We included patients from national reports and depicted the contribution of each country in this figure. Data from Canadian patients were extracted mainly from the International Severe Acute Respiratory and Emerging Infections Consortium (ISARIC) reports and described in Fig. 2, analysed together with other countries that were part of this international study [2].
Additionally, Dr Lipes found in a recent search three observational studies published between May and November 2020 that described patients in Canada and were not included in our review [[3], [4], [5]]. Our search was conducted up to 15 August 2020, and one of the studies cited was published after this period [5]. Despite our extensive review of literature, we missed one study in our search [4]. The other study was erroneously excluded, and we apologize for this [3]. Our study included a total of 69 093 patients, with 634 patients from Canada. These two missed studies (representing a total of 192 patients) would not change the results described, but we appreciate this contribution highlighting these studies and the results from Canada.
Outcomes from different studies can vary widely, as we described. The main purpose of our study was to describe the clinical course, interventions used and outcomes of coronavirus disease 2019 (COVID-19) intensive care unit patients according to the current literature worldwide, keeping in mind that regional differences can occur.
We agree that more studies are needed; future work can compare the interventions and outcomes as they changed from the beginning of the pandemic to the present day.
Transparency declaration
All authors report no conflicts of interest relevant to this response.
Editor: L. Leibovici
References
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