The number of road traffic deaths in China has soared almost 100% in two decades, reveals a study published in the journal Injury Prevention.
The pattern was not restricted to areas of major urbanisation and development, but was also seen in rural locations and sparsely populated areas, the findings show.
In 1990, road traffic injuries became the ninth leading cause of death and disability worldwide. They are set to shoot up to third place by 2020.
In China, the largest developing country in the world, road traffic injuries are already the leading cause of death in people up to the age of 45.
The authors used national statistics on transport and deaths police reports, and data on regional Gross Domestic Product (GDP), road quality, and the number of vehicles in each of the 31 provinces to inform their analysis and map the geographic distribution of road deaths between 1985 and 2005.
The findings showed that road traffic deaths increased 95% from 3.9 to 7.6 per 100 000 of the population between 1985 and 2005.
During this time, the number of cars on the road increased 9-fold, and the number of other vehicles, principally motorcycles, jumped by a factor of 54.
There was no link between the rate of deaths and regional GDP, road quality, or the average number of road vehicles in the province.
In general, the regions with the lowest population density had the highest overall death rates per 100 000 motor vehicles.
But the largest increases in death rates occurred in economically well developed provinces, but also in under developed and rural provinces.
Deaths in well developed areas can be explained by higher numbers of road vehicles, say the authors.
In less developed areas, the toll is likely to be explained by poor quality roads, making it difficult to access prompt medical care, a lesser degree of medical expertise, and greater vulnerability to injury as pedestrians and cyclists.
The authors note that the death rate levelled off slightly in 2002 and 2003, after having risen sharply in previous years, but this is not likely to be sustained as China's economic development continues at a rapid pace, and vehicle ownership grows, they say.
China's GDP increased by almost 11% in 2005, and road traffic deaths are expected to rise a further 92% between 2000 and 2020, especially as half of drivers don't wear seat belts.