Based on the reported number of road traffic deaths and the source of data, adjustments were made to account for the potential under-reporting due to differences in definitions as well as limitations in the Civil Registration and Vital Statistics (CRVS) in many countries. This process resulted in an estimated number of fatalities, which is presented along with the reported figure. Following this, a final consultation was carried out to allow Member States to respond to any changes that resulted from the verification and validation process. This consultation also provided Member States an opportunity to comment on the WHO estimates for road traffic fatalities, which is often much higher than the official statistics.
补充一下,建议关注同种族比较。比如,美国整体人均寿命确实不高,但亚裔寿命较高,为86岁,比日本还高,比美国白人长寿8岁。http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4567918/ 美国华裔女性期望寿命高达91岁。因为寿命和许多因素包括经济条件、生活方式、卫生条件等密切相关。在美国不同族裔寿命有显著差别。所以美国华裔并不用担心。Nationally, Chinese had the highest life expectancy (males e0 = 86.8; females e0 = 91.3) http://read.dukeupress.edu/demography/article/58/5/1631/178726/Examining-Ethnic-Variation-in-Life-Expectancy