pFIB-c Calculator
How to Calculate pFIB-c
The pFIB-c predicts liver fibrosis risk in pediatric MASLD using a logistic regression model.
FORMULA
The pFIB-c is calculated by the following formula:
\( x = -5.155 \)
\( + (1.194 \times \text{Sex [boy = 1, girl = 0]}) \)
\( + (1.636 \times \text{Hypertension [yes = 1, no = 0]}) \)
\( + (0.019 \times \text{ALT [U/L]}) \)
\( + (0.633 \times \text{Weight z-score}) \)
\( + (0.079 \times \text{HOMA-IR}) \)
\( - (2.453 \times \text{Black ethnicity [yes = 1, no = 0]}) \)
\( \text{Liver fibrosis risk, \%} = \frac{e^{x}}{1 + e^{x}} \times 100 \)
Notes:
* Both the CDC and WHO have resources to assist in the calculation of a weight z-score.
** HOMA-IR score = (Fasting insulin, uIU/mL) * (Fasting glucose, mg/dL) / 405
Enter the values and calculate the result.
Note: Ensure valid inputs; ALT, insulin, and glucose positive.
Using the pFIB-c Calculator
This calculator aids in predicting liver fibrosis risk in pediatric patients with metabolic dysfunction–associated steatotic liver disease (MASLD).
Input sex, hypertension, ALT, weight z-score, fasting insulin, fasting glucose, black ethnicity. The calculator computes HOMA-IR and outputs risk %, risk level, and correlated fibrosis stage.
Example 1: Boy, No hypertension, ALT 50, Weight z-score 1, Fasting Insulin 10, Fasting Glucose 81, No black ethnicity.
- Sex: 1
- Hypertension: 0
- ALT: 50
- Weight z-score: 1
- Fasting Insulin: 10
- Fasting Glucose: 81
- HOMA-IR: (10 * 81) / 405 ≈ 2
- Black ethnicity: 0
- x ≈ -5.155 +1.194 +0 +0.95 +0.633 +0.158 +0 ≈ -2.22
- Risk ≈ 9.82%
- Risk Level: Low
- Stage: F0-F1
Example 2: Girl, Yes hypertension, ALT 100, Weight z-score 2, Fasting Insulin 20, Fasting Glucose 100, Yes black ethnicity.
- Sex: 0
- Hypertension: 1
- ALT: 100
- Weight z-score: 2
- Fasting Insulin: 20
- Fasting Glucose: 100
- HOMA-IR: (20 * 100) / 405 ≈ 4.938
- Black ethnicity: 1
- x ≈ -5.155 +0 +1.636 +1.9 +1.266 +0.390 -2.453 ≈ -0.416
- Risk ≈ 39.75%
- Risk Level: Elevated
- Stage: ≥F2
Use for risk stratification.
Common FAQ
Below are frequently asked questions about pFIB-c:
- Q: What is pFIB-c?
A: Predicts liver fibrosis risk in pediatric MASLD.
- Q: What is HOMA-IR?
A: Homeostatic Model Assessment for Insulin Resistance.
- Q: How to get weight z-score?
A: Use CDC or WHO resources.
- Q: How accurate?
A: Validated in studies for pediatric patients.
- Q: For which patients?
A: Pediatric patients with MASLD.
Advice on Interpreting Results
Use to inform discussions on risks and care planning.
Facts & Figures
Interpretation:
| pFIB-c Score (Probability) |
Risk Level of Significant Liver Fibrosis |
Correlated Fibrosis Stage |
| <0.226 (22.6%) |
Low |
F0-F1 |
| ≥0.226 (22.6%) |
Elevated |
≥F2 |