Calculate disposition index from insulin sensitivity and insulin response, or solve for a missing IS or IR value with supported unit conversions.
- All Health and Medical Calculators
- Average Glucose To A1C Calculator
- Glucose to Insulin Ratio Calculator
Disposition Index Formula
The disposition index is calculated by multiplying insulin sensitivity by insulin response. The calculator can also rearrange the same equation to solve for either insulin sensitivity or insulin response when you enter the other two values.
- DI = disposition index, dimensionless for the AUC-based convention in this calculator
- IS = insulin sensitivity
- IR = insulin response
The calculator uses base units internally:
Select the value to solve for and enter the two required values. Use matched IVGTT sensitivity and incremental 0–10-minute insulin AUC, with unscaled sensitivity values. Conversion assumes 1 µU/mL = 6 pmol/L; confirm your laboratory convention.
Unit Conversions Used for Insulin Sensitivity and Insulin Response
| Input | Selected unit | Conversion to calculator base unit |
|---|---|---|
| Insulin sensitivity | min⁻¹ per µU/mL | Multiply by 1 |
| Insulin sensitivity | s⁻¹ per pmol/L | Multiply by 360 |
| Insulin response | µU/mL·min | Multiply by 1 |
| Insulin response | pmol/L·min | Multiply by (1/6) |
How to Read the Inputs and Result
| Value | What it represents | Important note |
|---|---|---|
| Insulin sensitivity | How strongly the body responds to insulin for glucose regulation. | Higher values generally mean greater insulin sensitivity. |
| Insulin response | The incremental 0–10-minute insulin AUC from the matched IVGTT protocol. | Use the same test method and time window when comparing results. |
| Disposition index | A combined measure of insulin sensitivity and insulin response. | There is no single universal cutoff. Interpretation depends on the test protocol and clinical context. |
Example Calculations
Example 1: Calculate disposition index
You enter:
- Insulin sensitivity = 0.0008 min⁻¹ per µU/mL
- Insulin response = 500 µU/mL·min
The disposition index is 0.4.
Example 2: Calculate insulin sensitivity
You enter:
- Disposition index = 0.75
- Insulin response = 1800 pmol/L·min
First convert insulin response to the base unit:
Then solve for insulin sensitivity:
The insulin sensitivity is 0.0025 min⁻¹ per µU/mL.
FAQ
What does the disposition index mean?
The disposition index combines insulin sensitivity and insulin response into one value. It is often used to describe how well insulin secretion compensates for insulin resistance. A lower value can suggest weaker compensation, but the result should be interpreted using the same testing method, population, and clinical context as the reference values being used.
Why is the disposition index unitless here?
The calculator converts insulin sensitivity and insulin response to matching base units before multiplying them. In this setup, the units cancel in the product, so the disposition index is reported as unitless.
Which values do I enter?
The equation has three variables: disposition index, insulin sensitivity, and insulin response. Choose a solve mode and enter the other two compatible measurements. A zero divisor cannot determine a unique sensitivity. This AUC-based convention differs from protocols that define insulin response as a mean concentration; do not compare their DI values directly.
