Risk stratification of patients admitted to hospital with covid-19 using the ISARIC WHO Clinical Characterisation Protocol: development and validation of the 4C Mortality Score
BMJ-BRITISH MEDICAL JOURNAL
Authors: Knight, Stephen R.; Ho, Antonia; Pius, Riinu; Buchan, Iain; Carson, Gail; Drake, Thomas M.; Dunning, Jake; Fairfield, Cameron J.; Gamble, Carrol; Green, Christopher A.; Gupta, Rishi; Halpin, Sophie; Hardwick, Hayley E.; Holden, Karl A.; Horby, Peter W.; Jackson, Clare; Mclean, Kenneth A.; Merson, Laura; Nguyen-Van-Tam, Jonathan S.; Norman, Lisa; Noursadeghi, Mahdad; Olliaro, Piero L.; Pritchard, Mark G.; Russell, Clark D.; Shaw, Catherine A.; Sheikh, Aziz; Solomon, Tom; Sudlow, Cathie; Swann, Olivia, V; Turtle, Lance C. W.; Openshaw, Peter J. M.; Baillie, J. Kenneth; Semple, Malcolm G.; Docherty, Annemarie B.; Harrison, Ewen M.
Abstract
OBJECTIVE To develop and validate a pragmatic risk score to predict mortality in patients admitted to hospital with coronavirus disease 2019 (covid-19). DESIGN Prospective observational cohort study. SETTING International Severe Acute Respiratory and emerging Infections Consortium (ISARIC) World Health Organization (WHO) Clinical Characterisation Protocol UK (CCP-UK) study (performed by the ISARIC Coronavirus Clinical Characterisation ConsortiumISARIC-4C) in 260 hospitals across England, Scotland, and Wales. Model training was performed on a cohort of patients recruited between 6 February and 20 May 2020, with validation conducted on a second cohort of patients recruited after model development between 21 May and 29 June 2020. PARTICIPANTS Adults (age a18 years) admitted to hospital with covid-19 at least four weeks before final data extraction. MAIN OUTCOME MEASURE In-hospital mortality. RESULTS 35 463 patients were included in the derivation dataset (mortality rate 32.2%) and 22 361 in the validation dataset (mortality rate 30.1%). The final 4C Mortality Score included eight variables readily available at initial hospital assessment: age, sex, number of comorbidities, respiratory rate, peripheral oxygen saturation, level of consciousness, urea level, and C reactive protein (score range 0-21 points). The 4C Score showed high discrimination for mortality (derivation cohort: area under the receiver operating characteristic curve 0.79, 95% confidence interval 0.78 to 0.79; validation cohort: 0.77, 0.76 to 0.77) with excellent calibration (validation: calibrationin-the-large=0, slope=1.0). Patients with a score of at least 15 (n=4158, 19%) had a 62% mortality (positive predictive value 62%) compared with 1% mortality for those with a score of 3 or less (n=1650, 7%; negative predictive value 99%). Discriminatory performance was higher than 15 pre-existing risk stratification scores (area under the receiver operating characteristic curve range 0.61-0.76), with scores developed in other covid-19 cohorts often performing poorly (range 0.63-0.73). CONCLUSIONS An easy-to-use risk stratification score has been developed and validated based on commonly available parameters at hospital presentation. The 4C Mortality Score outperformed existing scores, showed utility to directly inform clinical decision making, and can be used to stratify patients admitted to hospital with covid-19 into different management groups. The score should be further validated to determine its applicability in other populations. STUDY REGISTRATION ISRCTN66726260
Incorporating textual information in customer churn prediction models based on a convolutional neural network
INTERNATIONAL JOURNAL OF FORECASTING
Authors: De Caigny, Arno; Coussement, Kristof; De Bock, Koen W.; Lessmann, Stefan
Abstract
This study investigates the value added by incorporating textual data into customer churn prediction (CCP) models. It extends the previous literature by benchmarking convolutional neural networks (CNNs) against current best practices for analyzing textual data in CCP, and, using real life data from a European financial services provider, validates a framework that explains how textual data can be incorporated in a predictive model. First, the results confirm previous research showing that the inclusion of textual data in a CCP model improves its predictive performance. Second, CNNs outperform current best practices for text mining in CCP. Third, textual data are an important source of data for CCP, but unstructured textual data alone cannot create churn prediction models that are competitive with models that use traditional structured data. A calculation of the additional profit obtained from a customer retention campaign through the inclusion of textual information can be used by practitioners directly to help them make more informed decisions on whether to invest in text mining. (C) 2019 International Institute of Forecasters. Published by Elsevier B.V. All rights reserved.