Serious road injuries 2013; Estimate of the number of seriously injured road traffic casualties in the period 2011-2013. The number of serious road injuries (SRI) is an important indicator for lack of road safety. The number of SRIs is calculated in accordance with the international code MAIS2+, and is determined on the basis of two data sources BRON (police registration) and LMR (hospital data) on the assumption that all serious road injuries are registered in LMR. Broadly, the method consists of three parts: 1. the linking of both data files; 2. a correction for incompleteness of LMR and for crashes that did not occur on public roads; 3. a correction for incorrect classifications in LMR as not all road crash casualties can be identified in LMR; sometimes a wrong external cause is encoded. In recent years two developments occurred that made it necessary to adapt the method in 2013: • Hospitals switched to a different encoding system in recent years (from ICD9-cm to ICD-10). This transition means that the road crash casualties in the file that is supplied must be selected in a different manner. In 2012, almost half of the road crash casualties were registered by a hospital using ICD10. As a result, the calculated number of casualties for 2012 was less accurate. In 2014 SWOV made a conversion of ICD10 to ICD9. This made it possible to estimate the number of SRI in 2013 and to also make a more accurate calculation of the number of SRI in 2012. • Increasingly fewer casualties are registered in BRON, while at the same time LMR is becoming more incomplete. As a result of these developments, the numbers of casualties in some subgroups by injury severity and mode of transport became so small, that it resulted in a less accurate estimate of the total number of SRI. In addition, due to the small numbers in the subgroups, the casualties could no longer be stratified according to their characteristics, such as mode of transport, injury severity, age, gender and region. These developments made it necessary to adjust the method relative to previous years. The most important changes involve the determination of the number of SRI by region, mode of transport and injury severity (MAIS = 2, 3, 4, 5 +) being replaced by determination of the number of SRI for four different combinations of injury severity (MAIS2 and MAIS3 +) and crash type (with and without involvement of a motor vehicle). In addition, as a result of the transition to ICD-10 and the conversion to ICD9, the traffic selection from LMR has been adapted, by excluding the category horse riders (E827) and by (partly) adding the category 'not on public road' (E820- E825). Furthermore, a factor has been introduced that corrects for an average lighter injury severity encoding of ICD10-injury. Finally, some changes have been made in the factor that corrects for incompleteness of LMR (generated records) and the correction for cyclists who were involved in a crash 'not on public road ' is now made during another phase of the method. After the above adaptations of the method, SWOV has determined the number of serious road injuries in 2013 on 18,800. The numbers for 2012 and 2011 have been revised to 19,700, and 19,500 respectively (from 19,200 and 20,100 respectively). These numbers, however, should be used with caution, due to the limited quality of the link, and because of the transition to a new coding of injury severity since 2012. Compared with previous years, the estimated number of SRI with a relatively light injury severity of MAIS2 has declined in 2013. The number of SRI with more serious injury (MAIS3 +), however, has increased continuously since 2006. In 2013, the category MAIS3 + covers about one-third of the total number of SRI. The quality of the link seems to have increased somewhat in comparison with the years 2011 and 2012. Nevertheless, the quality is still insufficient to allow detailed stratification by mode of transport, injury severity and region in determining the SRI.
Samenvatting