Table 2. Relationship between the thyroid nodularity and the 131I ground deposition in the locations of residence after the nuclear accident.
| Number of lesions | Number of subjects | 131I ground deposition in the locations of residence (Bq/m2)a | |
| Total number of nodules b | 0 | 308 | 517 (482)c |
| 1 | 122 | 525 (539) | |
| 2 | 98 | 578 (552) | |
| 3 | 174 | 630 (513)d | |
| 4 or more | 435 | 536 (499) | |
| Number of solid nodules | 0 | 1,090 | 532 (498) |
| 1 | 41 | 601 (541) | |
| 2 | 5 | 286 (12,245) | |
| 3 or more | 1 | 578 (0) | |
| Number of cysts | 0 | 326 | 517 (486) |
| 1 | 121 | 526 (569) | |
| 2 | 85 | 568 (535) | |
| 3 | 174 | 635 (506)e | |
| 4 or more | 431 | 535 (500) |
a
Values of individual subjects were determined based on the data shown in Figure 1.
b
The sum of the numbers of solid nodules and cysts in each subject.
c
Median (IQR).
Non-parametric multiple comparison test with Kruskal-Wallis test was employed to analyze whether the 131I ground deposition differed as a function of the total number of nodules and the number of solid nodules or cysts.
d
Significantly different from the “zero-nodule” group (P = 0.007).
e
Significantly different from the “zero-cyst” group (P = 0.004).