isaric_4c_mortality: 4C Mortality Score for COVID-19

In cliot: Clinical Indices and Outcomes Tools

4C Mortality Score for COVID-19

Description

Calculates the ISARIC 4C Mortality Score to predict in-hospital mortality risk for patients admitted with COVID-19. This score was derived from a large UK cohort and outperforms many other risk stratification tools. It assigns patients to Low, Intermediate, High, or Very High risk groups.

Usage

isaric_4c_mortality(age, sex, comorbidities, resp_rate, o2_sat, gcs,
                    urea, crp, urea_units = "mmol/L", crp_units = "mg/L")

Arguments

age	Numeric. Patient age in years.
sex	String. Biological sex ("Male" or "Female").
comorbidities	Numeric. Number of relevant comorbidities (0, 1, or >=2). Relevant comorbidities include: Chronic cardiac disease, chronic respiratory disease (excluding asthma), chronic renal disease (eGFR <= 30), mild-severe liver disease, dementia, chronic neurological conditions, connective tissue disease, diabetes.
resp_rate	Numeric. Respiratory rate in breaths per minute.
o2_sat	Numeric. Peripheral oxygen saturation (%) on room air.
gcs	Numeric. Glasgow Coma Scale score (3-15).
urea	Numeric. Serum Urea or BUN level.
crp	Numeric. C-Reactive Protein level.
urea_units	String. Units for the urea input. Options: "mmol/L" (default) or "mg/dL" (treats input as Blood Urea Nitrogen/BUN).
crp_units	String. Units for the CRP input. Options: "mg/L" (default) or "mg/dL".

Value

A list containing:

Total_Score	The calculated 4C Mortality Score (Range 0-21).
Risk_Group	Risk classification (Low, Intermediate, High, Very High).
Est_In_Hospital_Mortality	Estimated mortality percentage based on the validation cohort.
Recommendation	Clinical management suggestion.

References

Knight SR, et al. 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. 2020;370:m3339. doi:10.1136/bmj.m3339

Examples

# Example 1: High Risk Patient
# 75yo Male, 2 comorbidities, RR 22, O2 91%, GCS 15, High Urea/CRP
isaric_4c_mortality(
  age = 75, sex = "male", comorbidities = 2,
  resp_rate = 22, o2_sat = 91, gcs = 15,
  urea = 15, crp = 120, urea_units = "mmol/L", crp_units = "mg/L"
)

# Example 2: Low Risk Patient
# 45yo Female, 0 comorbidities, Normal vitals and labs
isaric_4c_mortality(
  age = 45, sex = "female", comorbidities = 0,
  resp_rate = 16, o2_sat = 98, gcs = 15,
  urea = 4, crp = 10, urea_units = "mmol/L", crp_units = "mg/L"
)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.