The Haddon Matrix
If injuries are viewed as a disease similar to infection rather than an accident that is random and unpreventable, one can reasonably suspect that influencing predisposing factors may reduce the chance of injury.
Haddon was one of the pioneers of injury prevention and described a two-dimensional model for approaching injury and its causes.
The first dimension is the three factors of injury: host, agent or vector and environment.
The second dimension is the phase of injury divided into pre-event, event and post-event.
Using this model, any injury can be broken down into both its phases and contributing factors. A typical Haddon matrix using motor vehicle collision as an example is as follows. Note the bold text highlighting at first glance the identified relationship of gender to the matrix.
A Typical Haddon Matrix [2]
| Host | Agent/Vector | Environment |
Pre-event | Alcohol use | Brake condition | Visibility of hazards |
| Fatigue | Tire quality | Road curvature and gradient |
| Experience and Judgement | Center of gravity | Shoulder height |
| Risk-taking behaviour | Jackknife tendency | Surface coefficient of friction |
| Amount of Travel | Ease of control | Divided highways, one-way streets |
| Stature | Load weight | Intersections, access control |
| Medications | Speed capability | Weather |
| Motor Skills | Ergonomic controls | Signalization |
| Cognitive Function | Mirrors | Speed limits |
|
| Visual obstructions | Drunk driving laws |
Event | Seatbelt use | Speed at impact | Speed limits of traffic |
| Age | Direction of impact | Recovery areas |
| Sex | Vehicle size | Guard rails |
| Bone Density | Automatic restraints | Characteristics of fixed objects |
| Stature | Airbag | Median barriers |
|
| Character of contact surfaces | Roadside embankments |
|
| Load containment |
|
|
| Deformation zones |
|
|
| Fuel system integrity |
|
Post-event | Age |
| 911 access |
| Sex |
| EMS response |
| Medications |
| Triage and transfer protocols |
| Preexisting medical conditions/physical condition |
| EMS training |
| Social situation |
| Quality of emergency care |
|
|
| Location of appropriate ED |
|
|
| Access to definitive care |
|
|
| Access to rehabilitation services |
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2. Hargarten, J.W.R.a.S.W. (2002). Principles of the Disease of Injury. Rosen's Emergency Medicine. J.A. Marx. St. Louis, Missouri, Mosby Inc. 1:821-828.
