Graduated driver licensing for reducing motor vehicle crashes among young drivers

 

Abstract

Background

Graduated driver licensing (GDL) has been proposed as a means of reducing crash rates among novice drivers by gradually introducing them to higher risk driving situations.

Objectives

To examine the effectiveness of GDL in reducing crash rates among young drivers.

Search methods

Studies were identified through searching MEDLINE, EMBASE, CINAHL, Healthstar, Web of Science, NTIS Bibliographic Database, TRIS Online, SIGLE, the World Wide Web, conference proceedings, consultation with experts and reference lists in relevant published literature. The searches were conducted from the time of inception to May 2009, and the Cochrane Injuries Group conducted an updated search of the TRANSPORT database in September 2009.

Selection criteria

Studies were included if: 1) they compared outcomes pre- and post-implementation of a GDL program within the same jurisdiction, 2) comparisons were made between jurisdictions with and without GDL, or 3) both. Studies had to report at least one objective, quantified outcome.

Data collection and analysis

Results were not pooled due to substantial heterogeneity. Percentage change was calculated for each year after the intervention, using one year prior to the intervention as baseline. Results were adjusted by internal controls. Analyses were stratified by denominators (population, licensed drivers). Results were calculated for the different crash types and presented for 16 year-olds alone as well as all teenage drivers.

Main results

We included 34 studies evaluating 21 GDL programs and 2 analyses of >40 US states. GDL programs were implemented in the US (n=16), Canada (n=3), New Zealand (n=1), and Australia (n=1) and varied in their restrictions during the intermediate stage. Based on the Insurance Institute for Highway Safety (IIHS) classification, eleven programs were good, four were fair, five were marginal, one was poor and two could not be assessed. Reductions in crash rates were seen in all jurisdictions and for all crash types. Among 16 year-old drivers, the median decrease in per population adjusted overall crash rates during the first year was 15.5% (range -27 to -8%, five studies). There was a decrease in per population adjusted injury crash rates (median -21%, range -46 to -2%, five studies). Results for all teenage drivers, rates per licensed driver, and rates adjusting for internal controls were generally reduced when comparing within jurisdictions.

Authors' conclusions

GDL is effective in reducing crash rates among young drivers, although the magnitude of the effect varies. The conclusions are supported by consistent findings, temporal relationship, and plausibility of the association. Stronger GDL programs (i.e. more restrictions or higher quality based on IIHS classification) appear to result in greater fatality reduction. Future studies should focus on which components and combination of components yield the greatest reductions.

 

Plain language summary

Graduated driver licensing for reducing motor vehicle crashes among young drivers

Young drivers are at high risk of involvement in motor vehicle crashes. Graduated driver licensing (GDL) has been proposed as a means of reducing crash rates among novice drivers by gradually introducing them to higher risk driving situations. This review found 34 studies that have evaluated various types of GDL programs. All of the studies reported positive findings, with reductions for all types of crashes among all teenage drivers. However, the size of the reductions varied and, based on the included studies it is not possible to say which aspects of GDL programs have the biggest effect. Future research on GDL should evaluate the relative impact of different program components.

 

摘要

背景

分級駕照管理(Graduated driver licensing)以減少年輕駕駛的交通事故

藉由漸進式地引導初學者在風險較高的情況下駕駛，分級駕照管理(GDL)已經被提倡作為降低初學者的肇事率方法。

目標

檢驗分級駕照管理(GDL)在降低年輕駕駛之肇事率的效力

搜尋策略

包含MEDLINE, EMBASE, CINAHL, Healthstar, Web of Science, NTIS Bibliographic Database, TRIS Online, SIGLE, the World Wide Web，有關的會議記錄，向專家和作者諮詢的內容，以及參考文獻。搜尋本身並不限於某種語言以及出版狀態。

選擇標準

研究包括了：(1)比較在同一個司法管轄區域執行GDL計畫前和計畫後的成果，(2)比較有執行與沒有執行GDL計畫的司法管轄區域，或(3)以上兩者。研究報告至少要有一個客觀的，量化的結果。有2位評審獨立地審查搜尋結果，評估可能相關的全文，並以標準的格式納入研究。

資料收集與分析

其中1位評審摘錄資料,再由第2位評審審查。額外的資料則向作者索取。由於大量的非均質性的研究，結果顯示並不集中。此研究是以介入前1年做為基準的比率，來計算每年介入後的百分比變化並以內部控制(internal controls)來調整結果。資料分析則是利用不同的分母(人口、有牌照的司機)來分層。另外，根據不同型態的事故類型(整體、傷害、死亡、夜間、酒精，以及導致住院治療的事故)來計算結果。結果分別是單獨以16歲青少年和所有青少年駕駛呈現。

主要結論

我們納入了13個研究，此13個研究評估了12項的GDL計畫，實施期間為1979年到1998年間，實施國家包括美國(n = 7)，加拿大(3)，紐西蘭(1)，以及澳洲(1)。介於中間階段的計畫則依照各國家的限制而有所不同，例如：宵禁(8)；額外乘客人數的限制(2)；道路限制(1)。根據保險規定的高速公路安全分類計畫來看，並沒有一個GDL計畫是良好的，6個計畫是可以接受的，5個則是最低限度，而有1個計畫是不好的。在所有的司法管轄區以及所有的事故型態，都顯示出事故率的下降。在16歲的駕駛族群當中，第1年裡所有事故型態的肇事率，每人口下降的中位數比率為31%(26 – 41%)。每人口的傷害事故率則是差不多的(中位數：28%，4 – 43%)。比較各個管轄區，在所有青少年駕駛族群的結果中，平均每個有駕照的駕駛以及經過內部控制調整過的事故率，普遍都是有下降的。

作者結論

目前存在的證據顯示，GDL對於降低年輕駕駛的事故率是很有效的，儘管此效應的規模還不是很清楚。一致方向的結果、時間的關係以及協會的可信性都支持了這項結論。審查者也提出了對於GDL初步研就的建議(例如：研究方法、標準化報告的結果以及長期的追蹤)。這項研究也顯示出什麼是進行系統性評價的觀察研究所需要的(例如：品質評估工具)。

翻譯人

本摘要由高雄榮民總醫院金沁琳翻譯。

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

能夠有效降低年輕駕駛事故率的分級駕照管理有很高的風險和交通事故相關。藉由漸進式地引導初學者在風險較高的情況下駕駛，分級駕照管理(GDL)已經被提倡作為降低初學者的肇事率方法。然而，有相對少數研究被進行，目的是要看看GDL是不是真的有用。這篇文獻找到了13個評估各種類型的GDL計畫的研究，其中所有的研究都報告了正面的結果，也就是降低了青少年駕駛中，所有事故型態的肇事率。但是降低的程度各有不同，而且從現有的證據來看，並不能說明GDL計畫的哪一個方面提供最大的效應。因此作者建議將來應對GDL有更進一步的研究。