Background In Southeast Asia, motor vehicle traffic accidents have claimed more lives than HIV/AIDS. According to the World Health Organisation, the estimated GDP lost due to road traffic crashes in Thailand was around 3 percent in the year 2009–2010. Among those traffic fatalities, motorcycle-involved accidents were accounted more than 50 percent (WHO, 2013). Not wearing a helmet was among major causes of death by motorcycle traffic accidents. In contrast to growing number of motorcycles, Helmet Laws are not strictly enforced and largely ignored by drivers and passengers. The report by the Department of Disease Control, Thailand Ministry of Public Health (2010) showed that less than 50 percent of motorcyclists wore helmets.

Methods Both quantitative and qualitative research was applied in the study. The panel data was collected at the provincial level overtime for analysing the consequences of helmet use laws and other related policies by using the pooled time series model. In addition, there was a Quasi-Experimental Design for examining behaviours of motorcycle riders across the country.

Conclusions The policy-related factors including public safety education and health promotion in wearing helmet had significantly an impact on a reduction in motorcycle traffic fatalities in Thailand.