Table 1. Demographic characteristics of the participants of the external exposure screenings in Soma City.
| Year | 2011 | 2012 | 2013 | 2014* | 2015 | |
|---|---|---|---|---|---|---|
| Total participants (n = 14,405) | 3,812 | 3,824 | 2,979 | 1,937 | 1,853 | |
| Age (years; median: range) | 8 (0–15) | 8 (0–15) | 8 (1–15) | 8 (0–15) | 8 (0–15) | |
| Less than 6 (infants and pre-school) | 1,320 (34.6) | 1,221 (31.9) | 988 (33.2) | 302 (19.2) | 584 (31.5) | |
| 6–12 (Elementary school) | 1,854 (48.6) | 1,959 (51.2) | 1,591 (53.4) | 1,070 (68.0) | 1,038 (56.0) | |
| 13–15 (Junior high school) | 638 (16.7) | 644 (16.8) | 400 (13.4) | 201 (12.8) | 231 (12.5) | |
| Zones | ||||||
| 1 (Yamakami-district) | 157 (4.1) | 144 (3.8) | 123 (4.1) | 75 (3.9) | 56 (3.0) | |
| 2 (Yawata-district) | 231 (6.1) | 205 (5.4) | 177 (5.9) | 125 (6.5) | 119 (6.4) | |
| 3 (Tamano-district) | 23 (0.6) | 18 (0.5) | 12 (0.4) | 10 (0.5) | 11 (0.6) | |
| 4 (Akagi-area in Nittaki-district) | 26 (0.7) | 27 (0.7) | 22 (0.7) | 7 (0.4) | 8 (0.4) | |
| Other areas | 3375 (88.5) | 3430 (89.7) | 2645 (88.8) | 1720 (88.8) | 1659 (89.5) | |
*Age data is unavailable for 364 participants in 2014.