Application of CALL score for prediction of progression risk in patients with COVID-19 at university hospital in Turkey.

Background: The CALL score was developed as a predictive model for progressive disease. We aimed to validate and/or improve the performance of CALL score in our hospital settings.

Methods: Adult patients with polymerase chain reaction-confirmed COVID-19 were included in this retrospective observational study. Clinical and laboratory characteristics (including complete blood count, CRP, ferritin, LDH, fibrinogen, d-dimer) were obtained. ROC analysis was used for the evaluation of CALL score's performance. Cox regression analyses were performed for the selection of new parameters for improving CALL score.

Results: Overall, 256 patients were enrolled in the study. The median age was 54 (IQR, 22.5), 134 (52%) were women, 155 (61%) had at least one comorbidity, 60 (23%) had severe disease. The AUC value for CALL score for predicting progression to severe COVID-19 was 0.59 (95% CI 0.50-0.66). D-dimer on admission was associated with progressive disease (HR = 1.2 CI 95% 1.02-1.40), (P < .027).

Conclusion: The performance of the CALL score in our patient population was low compared with the original study. We found an additional parameter for predicting progressive COVID-19 disease, D-dimer, which may guide future studies to develop new scoring systems for predicting progressive disease.