valytics (version 0.4.1)

creatinine_serum: Serum Creatinine Method Comparison Dataset

Description

Synthetic dataset comparing serum creatinine measurements from two analytical methods: an enzymatic method (reference) and the Jaffe colorimetric method. This is a classic method comparison scenario where the Jaffe method is known to have positive interference from proteins and other chromogens.

Usage

creatinine_serum

Format

A data frame with 80 observations and 3 variables:

sample_id

Character. Unique sample identifier.

enzymatic

Numeric. Creatinine concentration (mg/dL) measured by the enzymatic method.

jaffe

Numeric. Creatinine concentration (mg/dL) measured by the Jaffe method.

Details

This synthetic dataset was designed to illustrate well-known patterns in creatinine method comparisons:

• Concentration range: 0.4-8.0 mg/dL, from normal kidney function to severe chronic kidney disease (CKD)

• Bias pattern: Jaffe method shows positive bias, more pronounced at lower concentrations due to pseudocreatinine interference

• Outliers: A few samples show larger positive bias, simulating interference from bilirubin, hemolysis, or ketones

The enzymatic method is more specific and has largely replaced the Jaffe method in modern clinical laboratories, though the Jaffe method remains in use in some settings due to lower reagent costs.

References

Peake M, Whiting M. Measurement of serum creatinine--current status and future goals. Clin Biochem Rev. 2006;27(4):173-184.

See Also

ba_analysis(), glucose_methods, troponin_cardiac

Examples

# Bland-Altman analysis
ba <- ba_analysis(enzymatic ~ jaffe, data = creatinine_serum)
summary(ba)
plot(ba)

# Note: Jaffe typically shows positive bias vs enzymatic