Changes in road safety following regional administrative reforms in Norway
研究了挪威2020年区域行政改革（郡县合并与道路管理权转移）对郡道受伤人数的影响，发现2020-2023年间无统计显著变化，适合关注政策与交通安全关系的读者。
• A reform of regional government in Norway took effect on January 1, 2020. • The management of county roads was transferred to counties. • During the period 2020–2023 no statistically significant changes in the number of injured road users were found. • The long-term effects if the reform should be studied some years from now. A reform of regional government in Norway was implemented on January 1, 2020. The management of county roads was transferred from the National Public Roads Administration to the counties. The number of counties was reduced from 19 to 11. In 2022 it was decided to split some of the counties that were merged in 2020, and the number of counties increased to 15 from January 1, 2024. This paper studies whether these reforms were associated with changes in the number of injured road users on county roads. Four counties and the city of Oslo were included in the study. The city of Oslo was not affected by the reforms in 2020 and 2024. The other counties were affected either by: (1) Transfer of the management of county roads only (one county); (2) transfer of the management of county roads and merger with another county (one county); or (3) transfer of the management of county roads and merger with another county, followed by splitting up the merged counties (two counties). A before-and-after study with comparison group using county roads as treated group and other public roads as comparison group, and 2010–2019 as before-period and 2020–2023 as after-period found very small changes in the number of injured road users. Trends established during 2010–2019 continued almost unchanged after 2020. It is concluded that the regional administrative reforms were not associated with any detectable changes in road safety in the counties included in the study.