Table 3.
Incidence rate ratio (RR) of thyroid cancer by level of exposure to alkylating agents (alkylating agent score) and dose of radiation to the thyroid gland. Modified after Veiga et al. (15)
| Radiation Dose (Gy) | ||||
|---|---|---|---|---|
| Exposure to Alkylating Agents (Score) |
≤20 | |||
| 0 RRa |
0–5 RRb |
0–20 RRb |
>20 RRb |
|
| Not exposed (0) | 1.0c | 1.0c | 1.0c | 1.0c |
| Low/medium(1–2) | 1.8 | 2.5 | 2.3 | 1.0 |
| Highly exposed (3) | 9.4 | 5.5 | 2.8 | 1.0 |
| P (trend) | 0.08 | 0.02 | 0.009 | 0.99 |
a
Adjusted for sex, natural log of attained age, type of first cancer (HL, leukemia, others)
b
Adjusted for sex, natural log of attained age, type of first cancer and radiation dose on continuous scale
c
Reference category