Table 1.
Numbers of Thyroid Cancer Cases, Participants, Person-Years (P-yrs) of Follow-Up, RR, 95% CI, and Estimated Radiation-Associated Excess Cases
| Dose (Gy) |
Cases | Participants | P-yrs | RRa | 95% CI | Excessb | |
|---|---|---|---|---|---|---|---|
| Range | Mean | ||||||
| 0 | 0.000 | 142 | 46,439 | 1,865,957 | 1.00 | 0.0 | |
| 0.001–0.004 | 0.002 | 24 | 9464 | 367,606 | 1.07 | (0.7, 1.8) | 0.4 |
| 0.005–0.02 | 0.009 | 30 | 13,796 | 587,614 | 1.21 | (0.8, 1.9) | 2.7 |
| 0.02–0.03 | 0.025 | 13 | 8055 | 345,748 | 0.87 | (0.5, 1.6) | 4.6 |
| 0.04–0.06 | 0.049 | 54 | 7204 | 315,014 | 2.01 | (1.4, 2.8) | 15.0 |
| 0.06–0.08 | 0.068 | 31 | 5825 | 256,456 | 1.40 | (0.9, 2.1) | 16.9 |
| 0.08–0.09 | 0.088 | 32 | 5535 | 242,247 | 1.78 | (1.2, 2.7) | 17.3 |
| 0.10–0.12 | 0.107 | 20 | 3220 | 136,943 | 2.51 | (1.5, 4.1) | 9.4 |
| 0.12–0.14 | 0.126 | 21 | 3537 | 149,525 | 2.63 | (1.6, 4.2) | 11.0 |
| 0.14–0.16 | 0.146 | 13 | 1778 | 73,824 | 3.76 | (2.1, 6.8) | 5.5 |
| 0.16–0.19 | 0.177 | 14 | 2741 | 113,582 | 2.41 | (1.4, 4.3) | 11.1 |
| Total | 394 | 107,594 | 4,454,516 | 93.8 | |||
Pooled data for doses <0.2 Gy.
a
RRs adjusted for study, sex, age, other study-specific factors, and chemotherapy exposure.
b
Estimated excess number of thyroid cancer cases above fitted background of nonexposed participants.