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Development and validation of risk prediction models for COVID-19 positivity in a hospital setting
Ming-Yen Ng1, Eric Yuk Fai Wan2, Ho Yuen Frank Wong3
1Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong Special Administrative Region; Department of Medical Imaging, The University of Hong Kong-Shenzhen Hospital, Shenzhen, Hong Kong Special Administrative Region.
Insights
Two validated risk prediction models for coronavirus disease-2019 (COVID-19) were developed using common hospital data. These models, presented as nomograms, aid in predicting COVID-19 positivity for clinical use.
Area of Science:
- Clinical Medicine
- Epidemiology
- Biostatistics
Background:
- Accurate prediction of coronavirus disease-2019 (COVID-19) positivity is crucial for effective patient management and resource allocation in healthcare settings.
- Developing reliable risk prediction models using readily available clinical parameters can significantly enhance diagnostic capabilities.
Purpose of the Study:
- To develop and validate two risk prediction models for COVID-19 positivity.
- To create nomograms and probability charts for practical clinical application in general hospitals.
Main Methods:
- A cohort of 1330 patients from four Hong Kong hospitals were included, with data randomly split for model development (n=895) and validation (n=435).
- Multivariable logistic regression was employed for model creation, with validation using the Hosmer-Lemeshow (H-L) test and calibration plots.
- Nomograms and probability calculations were generated to assess sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).
Main Results:
- Two prediction models were developed: Model 1 included age, white blood cell count, chest x-ray, and contact history (AUC=0.911).
- Model 2 excluded contact history but maintained strong predictive power (AUC=0.880).
- Both models demonstrated excellent external validation through H-L tests and calibration plots, confirming their reliability.
Conclusions:
- Two user-friendly, validated nomograms for COVID-19 risk prediction were successfully developed.
- These nomograms, based on accessible parameters, exhibit high accuracy (excellent AUCs) and are suitable for clinical implementation.
Objectives:
To develop: (1) two validated risk prediction models for coronavirus disease-2019 (COVID-19) positivity using readily available parameters in a general hospital setting; (2) nomograms and probabilities to allow clinical utilisation.
Methods:
Patients with and without COVID-19 were included from 4 Hong Kong hospitals. The database was randomly split into 2:1: for model development database (n = 895) and validation database (n = 435). Multivariable logistic regression was utilised for model creation and validated with the Hosmer-Lemeshow (H-L) test and calibration plot. Nomograms and probabilities set at 0.1, 0.2, 0.4 and 0.6 were calculated to determine sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV).
Results:
A total of 1330 patients (mean age 58.2 ± 24.5 years; 50.7% males; 296 COVID-19 positive) were recruited. The first prediction model developed had age, total white blood cell count, chest x-ray appearances and contact history as significant predictors (AUC = 0.911 [CI = 0.880-0.941]). The second model developed has the same variables except contact history (AUC = 0.880 [CI = 0.844-0.916]). Both were externally validated on the H-L test (p = 0.781 and 0.155, respectively) and calibration plot. Models were converted to nomograms. Lower probabilities give higher sensitivity and NPV; higher probabilities give higher specificity and PPV.
Conclusion:
Two simple-to-use validated nomograms were developed with excellent AUCs based on readily available parameters and can be considered for clinical utilisation.
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