1. What is the MDRD Equation?

The MDRD (Modification of Diet in Renal Disease) equation estimates glomerular filtration rate (GFR) from serum creatinine, age, sex, and race. It was developed to provide a more accurate assessment of kidney function than the Cockcroft-Gault formula.

2. How Does the Calculator Work?

The calculator uses the MDRD equation:

Where:

• \( Scr \) — Serum creatinine (mg/dL)
• \( age \) — Age in years
• 0.742 — Female multiplier
• 1.212 — African American race multiplier

Explanation: The equation accounts for the inverse relationship between creatinine and GFR, with adjustments for age, gender, and race.

3. Importance of GFR Calculation

Details: GFR estimation is essential for assessing kidney function, diagnosing chronic kidney disease, and determining appropriate medication dosages.

4. Using the Calculator

Tips: Enter serum creatinine in mg/dL, age in years, select gender and race. All values must be valid (creatinine > 0, age between 1-120).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between MDRD and CKD-EPI?
A: CKD-EPI is generally more accurate, especially at higher GFR levels (>60 mL/min/1.73m²), while MDRD may underestimate GFR in healthier individuals.

Q2: What are normal GFR values?
A: Normal is generally ≥90 mL/min/1.73m². Values below 60 for 3+ months may indicate chronic kidney disease.

Q3: When was the MDRD equation developed?
A: The MDRD equation was developed in 1999 based on data from the Modification of Diet in Renal Disease study.

Q4: Are there limitations to the MDRD equation?
A: Yes, it's less accurate for people with normal or near-normal kidney function and may not be ideal for drug dosing decisions.

Q5: Should I use MDRD or CKD-EPI?
A: CKD-EPI is now generally preferred, but MDRD may still be used in some clinical settings or for comparison with older studies.