Materials and methods
We investigated files of those patients admitted to Bursa City
Hospital/Bursa/Turkey between March-August 2020 with complaints
compatible with COVID-19. In a total 10000 patients retrospectively
evaluated. Out of 10000 patients those who were found to be positive for
Covid-19 and were completely healthy before the disease were included in
the study. In a total 318 Covid-19 patients who met the specified
criteria and 156 healthy controls those tested negatively and had no
chronic diseases included. We divided Covid-19 patients into two groups,
the main group consisted of those patients who had penumonia on computed
tomography of the lungs, the second gruop consisted of those patients
tested positively with PCR but had no penumonia on computed tomography
of the chest. And the third group consisted of healthy subjects. The
demographic and clinical data of all patients is shown on table 1. The
three patient groups were compared by examining the hemogram parameters
(WBC, neutrophil, lymphocyte, monocyte, eosinophil, platelets, PDW, MPV
and RDW) obtained at the time of hospital admission before using any
kind of medication. NLR, PLR and MLR values were calculated by dividing
neutrophil, platelet and monocyte levels to lymphocyte count. Patients
with chronic diseases, those using a medication and pregnants were
exluded. After obtaining scientific research approval for the study from
the Ministry of Health General Directorate of Health Services, the
ethics committee approval was obtained from Bursa City Hospital Clinical
Research Ethics Committee (Ethics Committee Approval No:2021-2/2). All
the statistical analyses were carried out using SPSS 25.0 software. A
Kolmogorov-Smirnov test was performed for the normality of the sample
data, and the continuous variables were defined by the mean ± standard
deviation, median (interquartile range %25–%75), while the
categorical variables were expressed as frequency and percent. In order
to compare the independent groups, One-way ANOVA Bonferroni for the
parametric test assumptions, and a MannWhitney U test for non-parametric
assumptions were used. The Roc analysis was performed for optimal
cut-off values to predict SARS-CoV-2 positivity. We exploited Youden
Index values to identify the optimal cut-off values. In addition, p
value less than 0.05 was set as the statistical significance level.