EANM Pediatric Dose Estimator
Use this calculator to estimate administered activity using an EANM-style weight multiplier or a simple linear scaling model. Enter your local protocol values and review the result before clinical use.
View EANM multiplier reference points used by this calculator
| Weight (kg) | Multiplier | Weight (kg) | Multiplier | Weight (kg) | Multiplier |
|---|---|---|---|---|---|
| 3 | 0.10 | 16 | 0.40 | 34 | 0.68 |
| 4 | 0.14 | 18 | 0.44 | 36 | 0.71 |
| 6 | 0.19 | 20 | 0.46 | 40 | 0.76 |
| 8 | 0.23 | 22 | 0.50 | 44 | 0.80 |
| 10 | 0.27 | 24 | 0.53 | 50 | 0.88 |
| 12 | 0.32 | 26 | 0.56 | 60 | 0.98 |
| 14 | 0.36 | 30 | 0.62 | 70 | 1.00 |
What an EANM dose calculator does
An EANM dose calculator helps convert a standard reference activity into a patient-specific activity, most commonly for pediatric nuclear medicine. Instead of giving every patient the same fixed MBq value, the dose is adapted to body weight using a multiplier curve.
This approach supports the core principle of nuclear medicine dosing: use enough activity for diagnostic quality while minimizing unnecessary radiation exposure.
Core formula
EANM-style multiplier method
Estimated activity (MBq) = Reference activity at 70 kg × Weight multiplier
The multiplier changes with body weight and is not purely linear across all small body weights. In practice, departments also apply tracer-specific minimum and sometimes maximum limits.
Linear fallback method
Estimated activity (MBq) = Reference activity × (Weight / 70)
Linear scaling is simpler and is included here as a comparison method, but many pediatric protocols prefer a dose-card style approach that better handles lower weight ranges.
How to use this calculator safely
- Enter the patient weight from a recent measured value.
- Enter the correct reference activity from your local protocol for the selected radiopharmaceutical.
- Apply your department’s minimum activity and any maximum cap.
- Use practical rounding based on syringe preparation workflow.
- Document the final prescribed activity and any adjustment reason.
Worked example
If your protocol reference activity is 185 MBq and the child weighs 20 kg, the EANM-style multiplier is approximately 0.46:
185 × 0.46 = 85.1 MBq
If minimum activity is 80 MBq and rounding is set to 1 MBq, the final value remains near 85 MBq (about 2.30 mCi).
Quality and governance checklist
- Verify patient identity and exam indication.
- Confirm tracer, route, and timing match protocol.
- Ensure calibration timing and decay correction are handled correctly.
- Cross-check the final number with a second qualified professional when required.
- Follow national law, local SOPs, and physician direction.