Binary and categorical domains relevant to exertional heat illness (EHI) susceptibility in military personnel
| Domain | Categories |
|---|---|
| Demographic and situational factors | |
| Occupational seniority | Recruits*; junior ranks; senior ranks and officers |
| Age | <30; >30 years |
| Prevailing climate | Hot climate*; temperate climate—summer months*; temperate climate—other months |
| Pacing of activity | Group-paced or self-paced |
| Clothing ensemble worn | Occlusive* (standard uniform +/− additional insulation, such as body armour);vented (reduced insulation relative to standard uniform, with exposure of bare skin below the elbow) |
| Individual susceptibility factors | |
| Physical fitness level | Physically fit§, or unfit* |
| Heat acclimatisation status | Acclimatised or unacclimatised* |
| Hydration state | Dehydrated* or euhydrated/overhydrated |
| Medical history | Positive for EHI* or no history of EHI |
| Sleep balance | Sleep deprived* or rested adequately |
| Febrile or infectious (intercurrent) illness | Present* or absent |
*Considered at increased risk of EHI by traditional risk stratification.
§Indicated by passing military fitness tests within 6 months prior to EHI episode.