CRB-65 Score Calculator

Overview

CRB-65 Score is used within Respiratory Medicine to support structured clinical assessment or calculation. Apply it only to an appropriate patient population and clinical setting.

Clinical Significance

The result can support assessment, communication and clinical planning, but it does not replace the complete history, examination, investigation, local policy or professional judgement.

When to Use

• Use only where the tool is applicable to the patient and clinical question.
• Confirm that all required inputs are current, accurate and entered in the correct units.
• Interpret the result alongside the complete clinical assessment and applicable local guidance.

How It Is Calculated

• The calculator applies the established variables, weights, equations or thresholds retained in the MedicalC calculation logic.
• Review the displayed input labels and final interpretation before using the result clinically.

Interpretation

• Interpret the result according to the category and explanation displayed by the calculator.
• Consider exclusions, confounders and urgent clinical features that may limit application.
• Do not use a single score or calculated value as the sole basis for diagnosis, treatment or disposition.

Worked Example

Enter a complete and internally consistent set of example observations, findings or laboratory measurements. The calculator applies the established method and returns the calculated value or score with its corresponding interpretation.

Patient Considerations

• Age, comorbidity, treatment already given, measurement quality and changes over time may affect interpretation.
• Use an age-specific or condition-specific alternative where the original method is not validated.

Limitations

• Performance may differ outside the original derivation or validation population.
• Missing, estimated, incorrectly converted or rapidly changing inputs can reduce reliability.
• The result does not replace clinical judgement, local pathways or specialist assessment.

Clinical Pearls

• Check eligibility and exclusions before calculating.
• Document the individual inputs as well as the final result.
• Recalculate when the patient’s condition or relevant measurements change.

Common Mistakes

• Applying the tool outside its intended patient population.
• Entering a value in the wrong unit or selecting an incorrect category.
• Allowing the calculated result to override urgent clinical concerns.

Evidence Base

The calculator preserves the established scoring or calculation logic and reference information from the existing MedicalC implementation. Its validity, thresholds and applicability remain dependent on the original evidence and subsequent clinical guidance.

References

1. Lim WS et al. Thorax. 2003;58:377–382. — Established source retained from the existing MedicalC calculator.