FIB-4 Index Calculator for Middle-Aged NAFLD Patient
Represents a 52-year-old patient with mildly elevated liver enzymes due to suspected non-alcoholic fatty liver disease (NAFLD).
Estimates liver fibrosis risk using age and common laboratory values (AST, ALT, and platelet count). Enter your Age, AST Level, ALT Level, Platelet Count to get an instant fib-4 score. Formula: round((age * ast) / (platelet_count * sqrt(alt)), 2).
FIB-4 Score
Fill in the fields above and click Calculate
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How It Works
How It Works
The FIB-4 Index Calculator estimates the risk of liver scarring (fibrosis) using four common lab values: age, AST, ALT, and platelet count. These values are combined into a single formula that produces one numeric score.
The calculator multiplies your age by your AST level, then divides that result by your platelet count multiplied by the square root of your ALT level. The final number is rounded to two decimal places and displayed as your FIB-4 Score.
- Uses 4 inputs: Age, AST, ALT, and Platelet Count
- Multiplies Age × AST
- Divides by Platelet Count × square root of ALT
- Returns one final score rounded to 2 decimal places
Understanding the Results
Your FIB-4 Score is a unitless number that helps estimate the likelihood of liver fibrosis. Lower scores generally suggest a lower risk, while higher scores may indicate a higher risk of significant liver scarring.
This score does not diagnose liver disease on its own. It is a screening tool that helps healthcare providers decide whether further testing may be needed.
- Lower scores usually suggest lower fibrosis risk
- Higher scores may indicate increased fibrosis risk
- The result is a screening estimate, not a diagnosis
- Discuss your score with a healthcare provider for proper interpretation
Frequently Asked Questions
What is the FIB-4 Index used for?
The FIB-4 Index is a non-invasive scoring system used to estimate the risk of liver fibrosis. It is commonly used in patients with chronic liver diseases such as hepatitis B, hepatitis C, or nonalcoholic fatty liver disease (NAFLD). The score helps determine whether further testing, such as imaging or biopsy, may be needed.
When should I use the FIB-4 calculator?
You can use the FIB-4 calculator when you have recent laboratory results for AST, ALT, and platelet count, along with the patient’s age. It is typically used during routine clinical evaluation of individuals with suspected or confirmed chronic liver disease. It is not intended for emergency diagnosis.
What units should I enter for the lab values?
Age should be entered in years. AST and ALT should be entered in units per liter (U/L), and platelet count should be entered in 10^9 per liter (10^9/L). Using the correct units ensures that the calculated FIB-4 score is accurate.
How is the FIB-4 score calculated?
The FIB-4 score is calculated using the formula: (Age × AST) ÷ (Platelet Count × √ALT). This formula combines age and liver-related laboratory markers to estimate the likelihood of liver fibrosis. The result is a single numeric value without units.
What does a higher FIB-4 score mean?
Higher FIB-4 scores are generally associated with a greater likelihood of significant liver fibrosis. Lower scores suggest minimal or no fibrosis. However, specific interpretation thresholds may vary depending on clinical guidelines and patient population, so results should be reviewed by a healthcare professional.
Can this calculator replace a liver biopsy?
No, the FIB-4 Index is a screening and risk stratification tool, not a definitive diagnostic test. While it can reduce the need for invasive procedures in some patients, a liver biopsy or advanced imaging may still be required for confirmation in certain cases.
Disclaimer
This health calculator is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Disclaimer.