title: Effects of excessive speeding and falling asleep while driving on crash injury severity in Ethiopia: a generalized ordered logit model analysis.
abstract: The severity of injury from vehicle crash is a result of a complex interaction of factors related to drivers' behavior, vehicle characteristics, road geometric and environmental conditions. Knowing to what extent each factor contributes to the severity of an injury is very important. The objective of the study was to assess factors that contribute to crash injury severity in Ethiopia. Data was collected from June 2012 to July 2013 on one of the main and busiest highway of Ethiopia, which extends from the capital Addis Ababa to Hawassa. During the study period a total of 819 road crashes was recorded and investigated by trained crash detectors. A generalized ordered logit/partial proportional odds model was used to examine factors that might influence the severity of crash injury. Model estimation result suggested that, alcohol use (Coef.=0.5565; p-value=0.017), falling asleep while driving (Coef.=1.3102; p-value=0.000), driving at night time in the absence of street light (Coef.=0.3920; p-value=0.033), rainfall (Coef.=0.9164; p-value=0.000) and being a minibus or vans (Coef.=0.5065; p-value=0.013) were found to be increased crash injury severity. On the other hand, speeding was identified to have varying coefficients for different injury levels, its highest effects on sever and fatal crashes. In this study risky driving behaviors (speeding, alcohol use and sleep/fatigue) were a powerful predictor of crash injury severity. Therefore, better driver licensing and road safety awareness campaign complimented with strict police enforcement can play a pivotal role to improve road safety. Further effort needed as well to monitor speed control strategies like; using the radar control and physical speed restraint measures (i.e., rumble strips).
authors.affiliation: School of Public and Environmental Health, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia. Electronic address: teferiabegaz@gmail.com.
authors.forename: Teferi
authors.initials: T
authors.lastname: Abegaz
authors.affiliation: Addis Continental Institute of Public Health, Addis Ababa, Ethiopia. Electronic address: yemaneberhane@gmail.com.
authors.forename: Yemane
authors.initials: Y
authors.lastname: Berhane
authors.affiliation: School of Public Health, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia. Electronic address: alemayehuwy@yahoo.com.
authors.forename: Alemayehu
authors.initials: A
authors.lastname: Worku
authors.affiliation: Ministry of Transport, Addis Ababa, Ethiopia. Electronic address: abebeasrt@yahoo.com.
authors.forename: Abebe
authors.initials: A
authors.lastname: Assrat
authors.affiliation: World Health Organization (WHO) Ethiopia, Addis Ababa, Ethiopia. Electronic address: abebayehua@et.afro.who.int.
authors.forename: Abebayehu
authors.initials: A
authors.lastname: Assefa
mesh_terms: D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000453:epidemiology*; D001334:Automobile Driving / Q000706:statistics & numerical data*; D004779:Environment Design / Q000706:statistics & numerical data*; D005002:Ethiopia / Q000453:epidemiology; D005221:Fatigue / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008029:Lighting; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011891:Rain; D012893:Sleep Wake Disorders / Q000453:epidemiology; D015599:Trauma Severity Indices; D055815:Young Adult
keywords: Generalized ordered logit model; Highway safety; Injury severity; Significant factors