Table 4:

Weighted incidence densities of mental disorders attributed at least partially to the Afghanistan mission, by demographic and military characteristics

Characteristic*Weighted incidence density, no. per 1000 person-years (95% CI)
Sex
Male31.8 (28.0–35.9)
Female39.6 (27.4–53.9)
Age, yr
< 3040.3 (32.9–48.0)
30–3928.9 (23.8–34.6)
≥ 4027.7 (20.0–37.0)
Component
Regular Forces31.9 (28.1–35.7)
Reserve Forces39.8 (22.2–62.6)
Element§
Land44.2 (38.6–50.5)
Sea18.5 (11.4–27.5)
Air15.7 (10.5–21.8)
Rank
Officer21.4 (13.6–30.6)
Senior NCM31.5 (23.2–41.0)
Junior NCM35.4 (30.5–40.5)
Deployment location**
Kandahar65.5 (55.6–76.2)
Kabul29.3 (22.2–38.0)
United Arab Emirates8.6 (3.2–14.9)
Arabian Gulf14.6 (7.6–23.3)
Multiple locations26.9 (21.6–32.8)
Unspecified19.2 (12.1–28.4)
No. of deployments††
134.0 (29.2–39.0)
231.3 (24.3–39.7)
≥ 317.0 (9.4–26.5)
Duration of first deployment, d
< 18028.7 (24.4–33.4)
180–36540.8 (33.4–48.6)
> 36517.0 (0.0–48.5)
Total duration of all deployments, d
< 18029.0 (23.7–34.5)
180–36538.3 (31.9–45.2)
> 36525.9 (17.8–36.3)
Overall32.5 (28.8–36.5)
  • Note: CI = confidence interval, deployment = deployment in support of Afghanistan mission, NCM = noncommissioned officer.

  • * Two-sample Z tests were used to compare differences in incidence density between variable levels; significance set at p < 0.05 after Bonferroni correction.

  • Sample design weights and bootstrap methods were used to compute the incidence density estimates and associated 95% CIs for the entire study population.

  • p < 0.05 for difference between groups aged < 30 and 30–39 yr.

  • § p < 0.05 for differences between Land and Sea Forces and between Land and Air Forces.

  • p < 0.05 for difference between officers and junior NCM ranks.

  • ** p < 0.05 for differences between Kandahar and each of the other locations, between Kabul and United Arab Emirates, and between “multiple locations” category and United Arab Emirates.

  • †† p < 0.05 for differences between ≥ 3 deployments and 1 deployment, and between ≥ 3 deployments and 2 deployments.