New Zealand Transport Agency Otago-Southland regional director Bruce Richards said 1551 crashes of that type in the 2004-08 period resulted in 44 people dying and 478 being seriously injured.
The total number of fatal crashes for the period was 78, and 986 people were seriously injured on Otago roads.
Last year, 21 people died and 188 were seriously injured in Otago, compared with 19 deaths and 163 serious injuries in 2007.
Mr Richards said most of the loss of control and head-on crashes were on rural roads, and vehicles "often end up hitting roadside hazards such as power poles or trees".
"The most commonly hit roadside hazards in Otago were cliffs or banks, fences and ditches."
Of those drivers who lost control, nearly 70% were male, and excessive speed and poor handling were the major contributors.
The next most frequent crash type was intersection crashes. Fourteen people died and 281 were seriously injured in 3406 crashes at Otago intersections over the five years to 2008.
The main causes were "poor driver observations", and failing to give way or stop. Road Policing Senior Sergeant Steve Larking said the three worst intersections in Dunedin for crashes were Frederick St-Cumberland St, George St-Duke St and King Edward St-Hillside Rd.
Nearly 2000 crashes in Otago over the five-year period involved drivers under 25 and resulted in 44 deaths and 544 serious injuries.
Mr Richards said, however, the 355 crashes involving young drivers last year was the lowest figure for more than five years.
"What is concerning is that two-thirds of those involved in these crashes were males, with 43% on either a learner or restricted licence. Just over half were in the 15-19 year-old age group."
