Table 1.
Overall demographic and examination-related characteristics of the examinations included in the study [median, range and interquartile range (IQR)]. They are shown for all the examinations, and for those obtained with the unit from Vendor 1 and from Vendor 2.
| Parameter | Total | Siemens | Hologic | |
|---|---|---|---|---|
| Number of exams | 17,777 | 12,125 (68.2%) | 5,652 (31.8%) | |
| Cancer prevalencea | 114 (6.4/1000) | 81 (6.7/1000) | 33 (5.9/1000) | |
| Age | Median | 58 | 58 | 57 |
| Range | 48 to 69 | 48 to 69 | 50 to 69 | |
| IQR | 54 to 63 | 54 to 63 | 53 to 63 | |
| Thickness (mm) | Median | 59 | 59 | 59 |
| Range | 13 to 117 | 13 to 117 | 16 to 106 | |
| IQR | 49 to 68 | 49 to 68 | 48 to 68 | |
| PDV (%) | Median | 10.15 | 9.86 | 10.78 |
| Range | 4.55 to 44.22 | 4.55 to 42.34 | 5.07 to 44.22 | |
| IQR | 8.11 to 13.55 | 7.83 to 13.23 | 8.75 to 14.20 | |
| Compression (N) | Median | 117 | 115 | 121 |
| Range | 16 to 275 | 16 to 220 | 25 to 275 | |
| IQR | 100 to 140 | 99 to 138 | 100 to 145 | |
| Glandular dose (mGy) | Median | 1.2 | 1.1 | 1.7 |
| Range | 0.04 to 5.2 | 0.04 to 4.1 | 0.5 to 5.2 | |
| IQR | 0.9 to 1.6 | 0.9 to 1.4 | 1.2 to 2.1 |
a
Ratio of positive cancer examinations, corroborated by biopsy as the gold standard.