Prehospital shock index in predicting mortality among patients with COVID-19.

Dear Editor,

We read with great interest the article titled “Association between prehospital shock index and mortality among patients with ” by Jouffroy et al. [1]. While we have a few suggestions for researchers, we request that researchers clarify some issues. First of all, it was said that the data collection task was carried out by a single investigator in order to minimize the bias in data abstraction. However, while abstracting data, at least two abstractors are required to ensure inter-rater reliability, and it it has been recommended to have four [2]. Additionally, data abstractors should be blind to the working hypothesis. It should be clarified whether a single investigator who did data abstraction in the current study was blind to the research hypothesis.

Previously, we investigated the usability of the shock index (SI) as a predictive tool in the emergency department and prehospital setting among patients with COVID-19 [3,4]. In these studies, we excluded patients with negative reverse-transcription polymerase chain reaction (RT-PCR) test results. The diagnosis of COVID-19 is made primarily by RT-PCR [5]. Jouffroy et al. did not apply any exclusion criteria in their study. In a retrospective research, missing data can result in a hidden or non-response bias in the results [6]. Therefore, it should be clarified how they deal with missing values without applying the exclusion criterion. They also gave as a limitation that the study populations were composed of suspected COVID-positives based on clinical signs and symptoms, not a PCR COVID test result. This situation can be confusing. For example, the article title should have been ‘......patients with suspected COVID-19’ instead of ‘......patients with COVID-19 disease’. Again, the word ‘disease’ in the title of the article is incorrect. Because the abbreviation of COVID-19 is ‘Coronavirus Disease 2019’.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Credit authorship contribution statement

A.K. Rohat: Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Software, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing. Fatih Doğanay: Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Software, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing.

Declaration of Competing Interest

Authors declare that they have no conflicts of interest.