Safety belt wearing by adult front seat occupants 2011

The latest annual national survey of safety belt use in New Zealand by adults in the front seats of cars and vans was carried out in March and April 2011. More than 90,000 drivers and adult front seat passengers were observed at 271 sites^[1] around the country. As in previous years, each site was surveyed between 10 am and 12 pm on normal working weekdays during the school term.

In 2011, the safety belt wearing rate for drivers and adult front seat passengers was 96 percent. This result indicates that the improvements made in earlier years, from 92 percent in 2003, are being maintained (see Table 1).

The wearing rates for various categories of front seat occupant are shown in Table 1. As observed in previous years, travellers on the open road had a higher wearing rate than those in urban areas (97 percent and 95 percent, respectively) and males were less likely to wear their safety belts (95 percent) than females (97 percent, also see Figure 1). Five percent of male drivers and eight percent of male passengers were not wearing a safety belt, compared to three percent of female drivers and three percent of female passengers. Over the last 10 years, wearing rates have increased significantly, especially for male drivers (90 percent in 2002 to 95 percent in 2011) and passengers (88 percent in 2002 to 92 percent in 2011).

Regional Wearing Rates

These restraint wearing surveys are designed to provide a consistent measure of safety belt use over time by surveying the same sites in each region each year.

Table 2 shows the safety belt wearing rates in each local government region over the last ten years. In 2011, at least 3,600 drivers and front seat occupants were surveyed in each region, except in Gisborne where 772 occupants were surveyed.

Overall, all regions show generally increasing trends in seatbelt usage since 2002. Seatbelt usage has increased significantly^[2] since last year in Manawatu - Wanganui (from 95 to 96 percent), West Coast (from 97 to 98 percent) and Canterbury (from 96 to 97 percent). It has decreased since last year in Northland (from 95 to 93 percent), Auckland (from 97 to 96 percent), Waikato (from 97 to 96 percent), Bay of Plenty (from 97 to 95 percent), and Hawke’s Bay (from 97 to 92 percent). Other regions have not changed markedly since last year.

Due to the effect of the 22 February 2011 Christchurch earthquake and the removal of three eastern Canterbury sites, the sample size in the Canterbury region is smaller than previous years. While the Canterbury sample size has gone down by 2,500, it is still the second largest sampled region in New Zealand, with 10,671 people observed.

* Statistically significant change from previous year.

Note. The accuracy of the wearing rates shown here depends on the sample sizes (the number of vehicle occupants observed). If the sample size is small, the data may show large random fluctuations in the observed wearing rate. Gisborne region is most affected, with a sample size of 600-900 occupants in 2002-2008. Typically, sample sizes in other regions have been over 1000 occupants prior to 2003 and over 3500 occupants since then.

Metropolitan Area Wearing Rates

Table 3 shows the wearing rates for selected metropolitan areas from 2003. Results from the previous cities of North Shore, Waitakere, Auckland and Manukau are now incorporated into Auckland, following their amalgamation in 2010. The observed front seat belt wearing rate has increased in Wellington City (from 97 to 98 percent), stayed steady in Hamilton, and decreased in all the other metropolitan areas examined.

Care should be taken in comparing the Christchurch metropolitan rate in 2011, with the earlier historical rates due to the removal of two eastern sites in the city due to the 22 February Christchurch earthquake. The sample size dropped from over 1500, to 699 people, and the sampled area no longer covered the eastern half of the city. In order to compare to 2010, the rate for 2010 for the western Christchurch sites surveyed in 2011 has been included.

** Statistically significant change from previous year.

Note. The accuracy of wearing rates shown here depends on the sample sizes (the number of vehicle occupants observed). If the sample size is small, the data may show large random fluctuations in the observed wearing rate.

Police District Wearing Rates

National restraint wearing surveys are designed to provide a consistent measure of safety belt use over time, by surveying the same sites in each district each year.

Seat belt use rates in Central and Canterbury have increased since 2010; both from 96 percent in 2010 to 97 percent. Rates have stayed static in Waitemata, Auckland, Wellington, Tasman and Southern. The other police districts have decreased between one and three percentage points, as shown in Table 4.

Due to the effect of the 22 February 2011 Christchurch earthquake and the removal of three of the Canterbury sites, the sample size for the Canterbury police district is smaller than previous years. While the Canterbury sample size has gone down by 2,300, 9,878 people were observed, which is still larger than the other two South Island police districts.

Table 4 shows the safety belt wearing rates in each police district over the last 10 years.

Local Authority Wearing Rates

Front seat safety belt wearing rates at territorial local authority (TLA) level are presented in Table 5. Where 500 or fewer people were sampled in a TLA, neighbouring local bodies have been combined for estimation.