ComeoCare and Units

Capturing patient parameters seems simple — until you realize that every number only makes sense when its unit is preserved.

In ComeoCare, handling units consistently across the application proved to be a design challenge.

Consider the variety of data a clinical application must handle: mass, volume, concentration, flow rates, and laboratory values such as hemoglobin or creatinine. Each parameter may be expressed in multiple units, and the preferred unit can vary from one hospital setting to another.

The complexity grows quickly:

• A value entered in kg must remain comparable to values stored in g or mg
• Calculations must preserve precision across conversions
• Historical data must remain interpretable years later, even if display preferences change
• Each clinical parameter requires its own default unit, and those defaults may evolve over time

The real challenge is not simply displaying the correct unit. It is ensuring that a value never loses its meaning, regardless of where or when it is used.

Our approach was to store every measurement as an inseparable pair: the numeric value and its unit, encoded together in the database using a structured format.

No orphaned numbers. No implicit assumptions. The meaning always travels with the data.

A small design decision — with a significant impact on clinical data consistency and long-term reliability.