Demographic and military characteristics of the study cohort (n = 30 513) and the chart-review sample (n = 2 014)
| Characteristic | Group; no. (%) of personnel | ||
|---|---|---|---|
| Study cohort | Chart-review sample | Weighted estimate* | |
| Sex | |||
| Male | 27 538 (90) | 1 772 (88) | 27 625 (91) |
| Female | 2 971 (10) | 242 (12) | 2 888 (9) |
| Unspecified | 4 (< 0.5) | 0 | 0 |
| Age, yr | |||
| < 30 | 12 282 (40) | 748 (37) | 11 395 (37) |
| 30–39 | 11 531 (38) | 803 (40) | 12 014 (39) |
| ≥ 40 | 6 695 (22) | 463 (23) | 7 104 (23) |
| Component | |||
| Regular Forces | 27 282 (89) | 1 870 (93) | 27 831 (91) |
| Reserve Forces | 3 227 (11) | 144 (7) | 2 682 (9) |
| Unspecified | 4 (< 0.5) | 0 | 0 |
| Element | |||
| Land | 19 634 (64) | 1 419 (70) | 19 278 (63) |
| Sea | 5 340 (18) | 223 (11) | 5 173 (17) |
| Air | 5 531 (18) | 372 (18) | 6 063 (20) |
| Unspecified | 8 (< 0.5) | 0 | 0 |
| Rank | |||
| Officer | 4 902 (16) | 308 (15) | 4 843 (16) |
| Senior NCM | 5 471 (18) | 369 (18) | 5 478 (18) |
| Junior NCM | 20 131 (66) | 1 337 (66) | 20 193 (66) |
| Unspecified | 9 (< 0.5) | 0 | 0 |
| Location of deployment | |||
| Kandahar | 12 745 (42) | 865 (43) | 12 745 (42) |
| Kabul | 4 144 (14) | 320 (16) | 4 144 (14) |
| United Arab Emirates | 3 125 (10) | 119 (6) | 3 125 (10) |
| Arabian Gulf | 5 260 (17) | 148 (7) | 5 260 (17) |
| Multiple locations | 4 655 (15) | 413 (21) | 4 655 (15) |
| Unspecified | 584 (2) | 149 (7) | 584 (2) |
| No. of deployments | |||
| 1 | 24 427 (80) | 1 547 (77) | 24 565 (81) |
| 2 | 5 155 (17) | 385 (19) | 4 911 (16) |
| ≥ 3 | 931 (3) | 82 (4) | 1 037 (3) |
| Duration of first deployment, d | |||
| < 180 | 18 150 (59) | 1 199 (60) | 18 282 (60) |
| 180–365 | 12 103 (40) | 792 (39) | 11 971 (39) |
| > 365 | 260 (1) | 23 (1) | 260 (1) |
| Total duration of deployments, d | |||
| < 180 | 14 827 (49) | 936 (47) | 15 010 (49) |
| 180–365 | 13 831 (45) | 910 (45) | 13 520 (44) |
| > 365 | 1 855 (6) | 168 (8) | 1 984 (6.5) |
Note: deployment = deployment in support of Afghanistan mission, NCM = noncommissioned officer.
↵* Sample design weights were used to compute descriptive statistics that were representative of the entire study population.