EBMcalc Logo
  COVID-19 Criticality Prediction (Yan 3/3/2020)

Percent Lymphocytes  

Important: Inputs must be complete to perform calculation.


Include literature references: Yes   No

  • This calculator represents findings from the literature referenced below. It is important to understand that these findings may not be representative of the experience in your local healthcare system.
  • This algorithm is based on a pre-print publication[1] and has not completed peer-review or methodological review yet. The results cannot be verified to be clinically accurate at your organization.
  • LDH: lactate dehydrogenase; hsCRP: high sensitivity C-reactive protein.

Calculation Details and Variables
  • Three predictive factors were discovered through machine learning using the XGBoost Classifier.[2]
  • A decision tree analysis starting with LDH measurement, and later hsCRP and the Percent Lmphocytes values were found to predict survival.
  • LDH >=365 U/L was associated with increased risk of death.
  • For lower LDH levels, an hsCRP level <41.2 mg/L was associated with increased probability of survival.
  • If the LDH was <365 U/L and the hsCRP was ≥41.2 mg/L, the Percent Lymphocyte value predicted outcome: In these cases, Percent Lymphocyte >14.7% were associated with increased survival while Percent Lymphocyte ≤14.7% were associated with increased mortality.

  1. Yan L, Zhang HT, Xiao Y, et al. Prediction of criticality in patients with severe Covid-19 infection using three clinical features: a machine learning-based prognostic model with clinical data in Wuhan. MedRxiv, the Preprint Server for health Sciences. https://www.medrxiv.org/content/10.1101/2020.02.27.20028027v2 accessed 3/17/2020.
  2. Chen T, Guestrin C. Xgboost: A scalable tree boosting system. arxiv e-prints. arXiv preprint arXiv:1603.0275, 2016.

Associated Logical Observation Identifiers Names and Codes [LOINC]
Parameter LOINC's and Suggested Units
LDH 14804-9 : U/L      14805-6 : U/L      2537-9 : U/L      
hsCRP 1988-5 : mg/L      30522-7 : mg/L      71426-1 : mg/L      76486-0 : nmol/L      
Percent Lymphocytes 736-9 : %      735-1 : %      737-7 : %      15197-7 : %      26478-8 : %      

This material contains content from LOINC (http://loinc.org). LOINC is copyright © 1995-2023, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license at http://loinc.org/license. LOINC® is a registered United States trademark of Regenstrief Institute, Inc.

Associated ICD10-CM Codes
   J12.9Viral pneumonia, unspecified
   J12.89Other viral pneumonia


Legal Notices and Disclaimer

All information contained in and produced by the EBMcalc system is provided for educational purposes only. This information should not be used for the diagnosis or treatment of any health problem or disease. THIS INFORMATION IS NOT INTENDED TO REPLACE CLINICAL JUDGMENT OR GUIDE INDIVIDUAL PATIENT CARE IN ANY MANNER. Click here for full notice and disclaimer.
EBMcalc is Copyright © 1998-2024 Foundation Internet    [Build 272652 v24.1]