Military Occupational Blast Exposure: Definition, Operationalization, and Validation of a Reproducible Risk Classification Metric.

The classification is based on job title, so it reflects the blast exposure a job usually involves rather than what any one person actually experienced. It identifies risk at group level and cannot separate exposed from unexposed individuals. The validation sample was service members and Veterans who had deployed to combat, so even the lower-risk group had plenty of opportunity for blast exposure. Lower risk here does not mean unexposed. The two datasets used somewhat different occupation coding, and the more detailed coding flagged roughly 1.4% more people as high risk than the other dataset would have. The analyses are descriptive and did not adjust for demographic or military factors that could affect both the job someone held and how much blast they encountered. Diagnoses and administrative records depend on people seeking care and on how care is documented, so mild TBI and symptoms are likely to be under-recorded. This is retrospective data, so the study cannot establish which came first, the exposure or the outcome.

The authors declare no conflicts of interest. No funding source is stated in the article text.

Do not read a lower-risk occupation as meaning the person was never exposed to blast. The authors state that their lower-risk group is a lower occupational risk group, not an unexposed group, and it was drawn from people who had deployed to combat.