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Consensus description of causes of failure.
| Attribute | 7% TLD, 7%/4 mm (%) | 5% TLD, 5%/4 mm (%) |
|---|---|---|
| Systematic | 11 (69) | 21 (58) |
| Low | 9 (56) | 17 (47) |
| High | 2 (13) | 4 (11) |
| Setup/position | 2 (13) | 4 (11) |
| Locala | 0 (0) | 8 (22) |
| Globalb | 3 (19) | 3 (8) |
Local errors included tests in which local phenomena caused only one TLD to fail, typically by a small margin (∼1%).
Global errors were those that resulted from multiple errors or irregular dose distributions.
