Operator-related factors:
(1) advanced age (which may be associated with slow response times, comorbid conditions, effects of medications and other factors)
(2) alcohol or drug intoxication
(3) effects of medications
(4) comorbid conditions
(5) inexperience
Tractor-related issues
(1) modifications made to the tractor
(2) improper use of the tractor
(3) repairing a tractor without proper precautions
(4) mechanical problems with the tractor (malfunction)
(5) lack of safety features
(6) farm implement using a power take off (PTO) shaft
Situation-related
(1) being thrown off the tractor (which may be related to failing to wear a seat belt)
(2) rollover (which may be related to operation and safety equipment)
(3) being struck by something (tree, etc)
(4) high risk activities (bush-hogging, logging, pulling something with a cable)
(5) poor visibility
(6) rain or snow
(7) driving through an overgrown field
