Table 2.
Mean volumetric density and percent volumetric density distributions by age group.
| Age (y) | Mean of the DV and VPD with the 95% confidence interval | |||
|---|---|---|---|---|
| Grade a | Grade b | Grade c | Grade d | |
| 35–39 | ||||
| DV | 37.34 (9.82–64.86) | 44.62 (41.22–48.03) | 55.63 (53.34–57.92) | 72.99 (71.00–74.98) |
| VPD | 2.95 (2.57–3.33) | 5.76 (5.58–5.95) | 11.82 (11.65–12.00) | 23.02 (22.78–23.25) |
| 40–44 | ||||
| DV | 35.5 (26.60–44.40) | 42.17 (40.38–43.96) | 54.56 (53.47–55.65) | 70.28 (69.15–71.40) |
| VPD | 3.07 (2.79–3.35) | 5.93 (5.82–6.04) | 11.76 (11.66–11.85) | 22.89 (22.75–23.04) |
| 45–49 | ||||
| DV | 32.84 (28.62–37.06) | 38.75 (37.89–39.61) | 50.76 (50.20–51.33) | 67.81 (67.11–68.51) |
| VPD | 3.19 (3.11–3.28) | 6.04 (5.99–6.10) | 11.59 (11.53–11.64) | 22.16 (22.07–22.25) |
| 50–54 | ||||
| DV | 33.5 (30.97–36.05) | 36.63 (36.09–37.17) | 47.3 (46.84–47.76) | 64.41 (63.62–65.20) |
| VPD | 3.17 (3.11–3.23) | 6.06 (6.02–6.09) | 11.16 (11.11–11.20) | 21.31 (21.21–21.41) |
| 55–59 | ||||
| DV | 34.23 (31.48–36.97) | 35.73 (35.28–36.19) | 45.29 (44.85–45.73) | 61.65 (60.55–62.75) |
| VPD | 3.13 (3.07–3.19) | 5.98 (5.95–6.02) | 10.80 (10.75–10.84) | 20.38 (20.26–20.51) |
| 60–64 | ||||
| DV | 30.83 (28.74–32.93) | 33.81 (33.41–34.21) | 43.41 (42.93–43.88) | 61.31 (59.77–62.85) |
| VPD | 3.20 (3.16–3.25) | 5.95 (5.92–5.98) | 10.47 (10.42–10.52) | 20.11 (19.94–20.29) |
| 65–69 | ||||
| DV | 30.82 (28.55–33.09) | 31.55 (31.13–31.98) | 41.15 (40.56–41.74) | 57.46 (55.18–59.74) |
| VPD | 3.20 (3.15–3.24) | 5.86 (5.82–5.89) | 10.35 (10.29–10.42) | 19.96 (19.71–20.22) |
The mean volumetric density (in cm3) and percent volumetric density (%) with 95% confidence intervals of healthy Taiwanese women are shown for the defined age groups. Excluding ages under 35 years and over 70 years, each group represents a 5-year span. The mammographic density grade was estimated in VDG by VolparaTM.
DV: volumetric density, VPD: percent volumetric density.