Table 3.
Example uncertainty analysis for measured film data from UW80-M data, expressed as percent.
| Uncertainty parameter | Type A | Type B | |
|---|---|---|---|
| Air kerma rate determination (ADCL) | 0.8 | ||
| X-ray field flatness | 0.3 | ||
| Film-to-film uniformity in one batch | 2.5 | ||
| Dose-rate film response | 1.5 | ||
| Film positioning | 0.3 | ||
| Shutter error | 0.1 | ||
| Pixel value uncertainty within ROI | 0.9 | ||
| Scan-to-scan uncertainty | 0.1 | ||
| Scanner drift | 0.1 | ||
| Quadratic sum | 0.9 | 3.1 | |
| A and B quadratic sum | 3.2 | ||
| Air kerma per film response % uncertainty (k=1) | 3.2 | ||
| Air kerma per film response expanded % uncertainty (k=2) | ±6.4 |