Hallvard Gjerde

Hallvard Gjerde
Oslo University Hospital · Department of Forensic Sciences

MS, PhD

About

149
Publications
37,076
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Introduction
Hallvard Gjerde currently works at the Department of Forensic Sciences, Oslo University Hospital. Hallvard does research in Forensic Science, Addiction Medicine and Toxicology. One of the main projects is 'Driving under the influence of alcohol or drugs'.

Publications

Publications (149)
Article
Objective: Using alcohol or psychoactive drugs before driving a motor vehicle may increase the risk of crash involvement, injury, and death. This is better documented for alcohol than for drugs. The aim of this study was to expand a previous case-control study on substance use and driver fatality by doubling the number of cases and controls, and h...
Article
Objective: Alcohol or drug impairment is a major risk factor for road traffic crashes, and studies on this issue are essential to provide evidence-based data for policymakers. In low- and middle-income countries (LMICs), such studies are often conducted in partnership with one or more organizations in high-income countries (HICs). The aim of this...
Article
Clinical signs of drug use can be helpful to identify which drug has been consumed. Amphetamine intake has traditionally not been considered to cause nystagmus. The aim of this study was to explore whether there is a relationship between amphetamine use and nystagmus in a population of apprehended drivers in a naturalistic setting. We evaluated dri...
Article
Objective: Driving under the influence of alcohol or drugs is one of the main contributing causes of serious road traffic crashes (RTCs). This study aimed to investigate the involvement of alcohol and drugs in driver fatalities in Norway during 2011-2020 and compare the findings with data from the previous decade. Methods: We linked the results...
Article
Full-text available
Background: Tetrahydrocannabinol (THC) is the most frequently detected drug in blood samples from apprehended drug driving suspects in Norway. This investigation aimed to study the extent of polysubstance use among apprehended crash-involved drivers with THC concentrations above the legal limit and explore the importance of THC in polysubstance ca...
Article
Aim Clinical signs of drug use can be helpful to identify which drug has been used. Amphetamine intake has traditionally not been considered to cause nystagmus; however, there is a lack of evidence for this claim. The aim of this study was to find a relationship between amphetamine use and nystagmus in a population of apprehended drivers. Method W...
Article
Aim This study aims to determine the prevalence of alcohol among injured road traffic crash victims (motor vehicle drivers, motorcycle riders, and pedestrians) admitted to three major health centers in Cameroon (one in Douala and two in Yaoundé). This study also investigated the associations between alcohol use and some socio-demographic and injury...
Article
Cannabis is the second most commonly used impairing substance by drivers, after alcohol. As more countries legalize cannabis, there is concern that cannabis-impaired driving will increase. In many countries, police use roadside devices to test for oral fluid THC (the primary psychotropic component in cannabis) to identify drivers who used cannabis;...
Book
Full-text available
Use of alcohol, illicit drugs, or psychoactive medicinal drugs are contributing factors in many road traffic crashes. In this report, we have compiled analytical results from blood samples taken from deceased motor vehicle drivers in the period 2001-2020. In most cases, the blood samples were taken at legal autopsy, but in some cases immediately af...
Article
Full-text available
Introduction: In previous research projects and clinical settings, alcohol analysis in oral fluid (saliva) has been used as an alternative to breath or blood alcohol testing. In this study we examined whether it is possible to obtain clinically relevant data regarding alcohol consumption in individuals who recently consumed alcohol by analysing or...
Article
The use of alcohol among road users injured in road traffic crashes and admitted to three major hospitals in Cameroon was studied. Alcohol use was measured using breathalyzers, and data on age, gender, education level, religion, type of road user, time of the crash, crash characteristics, and injury severity were recorded using a questionnaire. Of...
Article
Introduction Alcohol and illicit drugs impair cognitive and psychomotor skills and may thereby increase the risk of involvement in a road traffic crash and other types of injuries. However, the knowledge on the use of psychoactive substances among injured patients presenting to emergency departments in low and middle-income countries remains limite...
Article
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Background People who inject drugs (PWID) have a high risk of premature death due to fatal overdoses. Newly emerged fentanyls, much more potent than heroin and other opioids, may increase this risk further. Therefore, precise information on injected drugs is critical to improving prevention strategies. Aims This study aimed to analyse drug residue...
Article
Full-text available
Background Nightclubs and bars are recreational settings with extensive availability and consumption of alcohol and recreational drugs. Objectives This study aims to determine the proportion of nightclub patrons in Norway that tested positive for illicit drugs, moreover, we examined the correlation between positive test results and demographic and...
Article
Full-text available
Objective: This study aimed to assess the prevalence of drinking and driving on roadways in urban areas and highways in Cameroon, and to determine the associations between drinking and driving and socio-demographic factors. Methods: A cross-sectional study of motor vehicle drivers was performed on Fridays, Saturdays, and Sundays between May and...
Article
Full-text available
Objective To study the prevalence of alcohol and drugs in biological samples from drivers, motorcycle riders, bicyclists, and pedestrians involved in fatal road traffic crashes (RTCs) during 2016-2018 in Norway, both among fatally injured victims and those who survived fatal RTCs. Methods Anonymous information was extracted from police data. No pe...
Article
Full-text available
Background : Road traffic injuries are a leading cause of death and disability, especially in low- and middle-income countries. Identifying injury hotspots are valuable for introducing preventive measures. This is usually accomplished by using police data, but these are often unreliable in low-income countries. This study aimed to identify hotspots...
Article
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Background: Pedestrian and cyclist injuries are a major concern globally, but especially in low-income countries. Locally conducted research is needed to measure the size of the problem and advise policy on road safety interventions. We wanted to investigate the precise circumstances of these injuries in Lilongwe, Malawi and to identify risk facto...
Article
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Background Alcohol consumption is a well-known risk factor for sustaining road traffic injuries worldwide. Malawi is a low-income country with a large and increasing burden of road traffic injuries. It has generally been viewed as a country with relatively little alcohol consumption. This study investigates the role of alcohol in road traffic injur...
Book
Full-text available
Aims of the study: To determine the prevalence of alcohol or drug impairment in fatal road traffic crashes in Norway during 2005-2018, primarily among fatally injured motor vehicle drivers (including riders), and assess the degree of impairment and prevalence of problematic use of alcohol or drugs. Alcohol and drug impairment was studied in relatio...
Article
Background: The ratio between the concentrations of drugs in the oral fluid and blood (OF/B ratio) reflects the transfer of drugs from blood to oral fluid, which is influenced by several factors such as oral fluid contamination. OF/B drug concentration ratios for psychoactive drugs, including inter-individual variation, were investigated in this s...
Article
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Objective: To investigate whether the use of recommended therapeutic doses of medicinal drugs has led to suspicion of driving under the influence of drugs (DUID) after implementation of legislative limits for illicit and medicinal drugs in 2012. Methods: Data from suspected drug-impaired drivers apprehended by the police from 2013 to 2015 were sele...
Article
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Background/aim: Drug use and risky driving is associated with sensation seeking. The aim of this study was to investigate the association between use of psychoactive substances and levels of the sensation seeking personality trait as measured with the Brief Sensation Seeking Scale 4 among drivers in Norway. Method: A cross-sectional design was a...
Poster
Full-text available
First international communication of results from IDART was awarded best poster price at London Trauma Conference 2019
Preprint
Full-text available
Background/aim Drug use and risky driving is associated with sensation seeking. The aim of this study was to investigate the association between use of psychoactive substances and levels of the sensation seeking personality trait as measured with the Brief Sensation Seeking Scale 4 among drivers in Norway. Method A cross-sectional design was applie...
Preprint
Full-text available
Background Drug use and risky driving is associated with sensation seeking. The aim of this study was to investigate the association between use of psychoactive substances and levels of the sensation seeking personality trait as measured with the Brief Sensation Seeking Scale 4 among drivers in Norway. Method A cross-sectional design was applied to...
Article
Objective: Road traffic crashes (RTCs) are responsible for a large number of deaths worldwide, but low- and middle-income countries frequently present higher rates of deaths; for example, Norway, a high-income country, has a rate of 2.0 drivers killed per 100,000 inhabitants, whereas Brazil, a middle-income country, has a rate of 18.4. A significan...
Article
Background: Self-reported data are commonly used when investigating illicit substance use. However, self-reports have well-known limitations such as limited recall and socially desirable responding. Mislabeling or adulteration of drugs on the illicit market may also cause incorrect reporting. Objectives: We aimed to examine what could be gained in...
Article
Fatal road traffic crashes are often related to speeding, non-use of a seatbelt, and alcohol/drug-impaired driving. The aim of this study was to examine associations between driving under the influence of drugs and/or alcohol and driver-related risk factors that have been reported as significantly contributing causes of fatal road traffic crashes....
Article
Experimental, epidemiological, and real-case studies have different advantages and limitations when used to study the effect of substance use on the risk for involvement in a road traffic crash. It is easier to perform well-controlled experimental studies than well-controlled epidemiological studies due to difficulties related to selection bias, in...
Article
Purpose: We aimed to study the pharmacokinetics of methadone and buprenorphine in blood and oral fluid after single-dose administration and investigate correlations between concentrations in blood and neurocognitive functions. Methods: A 5-way, double-blind, randomized, placebo-controlled, double-dummy, crossover study was performed to study the...
Article
Objective: Norway introduced a “Vision Zero” strategy in 2001, using multiple approaches, aiming toward a future in which no one will be killed or seriously injured in road traffic crashes (RTCs). Official statistics show that the number of fatally injured road users has declined substantially from 341 deaths in 2000 to 117 in 2015. In-depth crash...
Article
Objective: Truck drivers represent a group that is susceptible to the use of stimulant substances to reduce the symptoms of fatigue, which may be caused by a stressful and exhausting work environment. The use of psychoactive substances may increase the risk for involvement in road traffic crashes. Previous studies have demonstrated that amphetamin...
Article
Background: Use of illicit substances is often under-reported. Testing positive in oral fluid provides an objective confirmation of recent intake. Objectives: To examine the agreement between oral fluid test results and self-reported substance use among music festival attendees, and factors associated with reporting past 48 h drug use among user...
Article
Full-text available
Background and objectives: Even though nightlife studies with potentially intoxicated participants provide the much needed information on drug use, they face additional methodological challenges. This study aimed to explore the utility of such studies by (i) classifying nightlife attendees based on their self-reported drug use and by (ii) examinin...
Article
Objective: The objective of this study was to study the association between self-reported road traffic crashes (RTCs) and recent use of alcohol and medicinal and illicit drug use and self-reported speeding in the previous 2 years. Methods: During the period from April 2016 to April 2017, drivers of cars, vans, motorcycles, and mopeds were stopped i...
Article
Aims: Illegal substance use at music festivals is less documented than it is in nightlife and electronic dance music settings. This study investigated such use through questionnaires, breathalysers and oral fluid drug testing. We also examined the associations between testing positive for illegal substances and demographics, self-reported substanc...
Article
Full-text available
Objectives The rate of deaths caused by road traffic crashes is particularly high in rural areas. It has been hypothesised that one factor that may contribute is differences in patterns of alcohol use. The aim was to compare the prevalence of psychoactive substances among crash-involved drivers arrested for suspicion of driving under the influence...
Article
Full-text available
Aims The present study assessed the acute effects of methadone and buprenorphine on actual on‐road driving performance and neurocognitive function. Methods Methadone (5 and 10 mg per os) and buprenorphine (0.2 and 0.4 mg sublingual) were administered to 22 healthy volunteers in a five‐way, double‐blind, randomized, placebo‐controlled, double‐dummy...
Article
Simultaneously collected samples of oral fluid and blood in a naturalistic setting could provide a qualitative impression of the relative detection times of drugs in oral fluid compared to blood. The aim of this study was to compare detections of different drugs in oral fluid and blood from a large material of paired samples. The study included res...
Article
Purpose: To determine and discuss common weaknesses and errors in case-control studies on the association between drug use and road traffic crash injury among drivers and recommend improvements for future studies. Methods: A search for case-control studies published between 2000 and 2016 was performed using PubMed and other databases in addition...
Article
Objective: To study the use of alcohol and drugs among the general driving population in the south-eastern part of Norway and to compare the findings with the results from a similar roadside survey in 2008-9. Methods: A roadside survey of drivers of cars, vans, motorcycles and mopeds was performed from April 2016 to April 2017 in collaboration with...
Article
Cocaine is a potent stimulant drug widely abused that exists in two forms: as a hydrochloride salt and as a free base (crack). Cocaine and the inactive metabolite benzoylecgonine can be determined to reveal any kind of cocaine use, whereas the pyrolysis product anhydroecgonine methyl ester (AEME) can be determined to reveal crack smoking. There are...
Article
Full-text available
Driver fatalities in motor vehicle collisions (MVCs) encompass accidents, suicides, and natural deaths when driving. The objective of this study was to determine the significance of pathology and other autopsy findings for drivers in fatal MVCs. Forensic autopsy records of driver fatalities in southeast Norway between 2000 and 2014 were studied ret...
Article
Reliable field testing devices for psychoactive drugs would be useful tools for the police for detecting drug-impaired drivers. The Norwegian Mobile Police Service (NMPS) started using Dräger DrugTest 5000 (DDT5000) in 2015 as an on-site screening instrument for drugs in samples of oral fluid. The aim of this study was to compare the results of fie...
Article
This study describes trends in drug use among drivers suspected of driving under the influence of drugs, apprehended by the police in Norway during 1990-2015. Chromatographically determined toxicological findings in blood samples were retrospectively investigated. Drug findings above defined cut-off concentrations were considered positive; hence ma...
Article
Objective: The availability of cannabis in Norway seems to have increased according to seizures by customs and police. On the other hand, national population surveys have not found any increase in self-reported use of cannabis. This investigation aimed at studying trends in cannabis use among suspected drug-impaired drivers apprehended by the poli...
Article
Traffic accidents are responsible for 1.25 million deaths worldwide and are the most common cause of death among those aged 15-29 years. In Brazil, traffic accidents caused more than 44,000 deaths in 2014. The use of psychoactive drugs is an important risk factor for being involved in traffic accidents. Previous studies have found that psychoactive...
Article
Objective: To determine the prevalence of alcohol and potentially impairing drugs among the general driving population in Finnmark and to compare the prevalence among Norwegian, Russian and other foreign drivers by analyzing samples of oral fluid. Methods: In collaboration with local police, drivers were selected for a voluntary and anonymous study...
Article
Experimental studies on the impairing effects of drugs of relevance to driving-related performance published between 1998 and 2015 were reviewed. Studies with on-the-road driving, driving simulators, and performance tests were included for benzodiazepines and related drugs, cannabis, opioids, stimulants, GHB, ketamine, antihistamines, and antidepre...
Article
Cannabis;case-control;culpability;driving;driving under the influence;DUI;impairment
Article
Clonazepam, nitrazepam and flunitrazepam are frequently used benzodiazepines, both as prescribed medication and as drugs of abuse. Little is, however, known about how these drugs are excreted in oral fluid. It has been claimed that the parent drugs are more likely to be detected in oral fluid than the 7-amino metabolites. The aim of this study was...
Article
Trends in the use of alcohol and drugs among motor vehicle drivers in Australia, Brazil, Norway, Spain, and the United States have been reviewed. Laws, regulations, enforcement, and studies on alcohol and drugs in biological samples from motor vehicle drivers in general road traffic and fatal road traffic crashes (RTCs) are discussed. Roadside surv...
Article
Full-text available
Background: Alcohol or drug use and associated hangover may reduce workplace safety and productivity and also cause sickness absence. The aims of this study were to examine (i) the use of alcohol and drugs, and (ii) reduced efficiency at work and absence due to such use among employees. Methods: Forty-four companies were invited; half of them ag...
Article
To assess whether analysis of oral fluid can be used to identify individual drivers with drug concentrations in blood above 25ng/mL for amphetamine and methamphetamine, 10ng/mL for cocaine and 1.0ng/mL for tetrahydrocannabinol (THC), which are the cut-off concentrations used in the European DRUID Project, by calculating the diagnostic accuracies wh...
Article
Epidemiological studies of the association between drug use and involvement in road traffic crashes (RTCs) published from January 1998 to February 2015 have been reviewed. Cohort and population studies compared RTC involvement among drug users and non-drug users, case-control studies compared drug use among RTC-involved and non-RTC-involved drivers...
Article
The aim of the study was to examine the prevalence of alcohol and drugs in blood samples from motorcycle riders who died in road crashes in Norway from 2001 to 2010. An additional aim was to compare the prevalence of alcohol and drugs in blood samples from fatally injured motorcycle riders and car drivers who died during the same time period. Blood...
Article
For many years, flunitrazepam was the benzodiazepine of choice among users of illegal drugs. The aim of this study was to investigate to which extent clonazepam use has increased in this population, and whether this was related to increased prescription or because of illegal availability. We used data from three sources to study the changes in the...
Article
Since 2005, all fatal road traffic crashes in Norway have been analyzed in-depth by multidisciplinary investigation teams organized by the Norwegian Public Roads Administration (NPRA). During the period 2005-2010, 608 drivers of cars or vans were killed in road traffic crashes. Blood samples were collected from 372 (61%) of the drivers and analyzed...
Article
Objectives: To examine the prevalence of alcohol and drugs in blood samples collected from car and van drivers killed in traffic accidents in Norway during the time period from 2001 to 2010. Methods: Blood samples (n = 676, 63% of all killed drivers) were analyzed for alcohol, psychoactive medications, and illicit drugs. The cutoff limits for po...
Article
Objective: To investigate whether the use of the stimulants amphetamines and cocaine by truck drivers in Brazil was related to travel length. Methods: Truck drivers were randomly stopped by the Federal Highway Police on interstate roads in Sao Paulo State during morning hours from 2008 to 2011 and invited to participate in the project "Comandos...
Article
The aim of this study was to determine the association between drug type and arrest for driving under the influence of drugs (DUID) by calculating odds ratios (ORs) using a case-control design. A DUID arrest is in most cases related to aberrant or risky driving and might therefore be regarded as a proxy for a drug related traffic crash. The 'cases'...
Article
Full-text available
Working under the influence of drugs and/or alcohol may affect safety and job performance. However, the size of this possible problem among health professionals (HPs) is unknown. The aim of this study was threefold: (i) to analyze samples of oral fluid and self-reported data from questionnaires to investigate the prevalence of alcohol and drugs amo...
Article
Oral fluid is an easily available specimen for studying drug use in a cohort or population. The prevalence of drugs in samples of oral fluid is the same as the prevalence in blood if using equivalent cutoff concentrations. The cutoffs in oral fluid may be higher or lower than that in blood in accordance with the median oral fluid-to-blood (OF/B) co...
Article
Objective: Recent Norwegian and Finnish studies have found high odds ratios for serious or fatal injury in road traffic accidents among drivers after drinking alcohol. In this report we have compared the odds ratios with results from studies in other countries. Methods: A literature review was conducted. Results: The odds ratios were significa...
Article
Analysis of samples of oral fluid (mixed saliva) is increasingly being used to detect recent drug use. The aim of this investigation was to assess the suitability of testing oral fluid as a biomarker for the presence of 4 benzodiazepines in blood and its possible application in clinical settings and in research on drug use. Paired samples of oral f...
Article
The relationship of drug concentrations between oral fluid and whole blood was evaluated by studying the linear correlation of concentrations and calculating the oral fluid to blood concentration ratios (OF/B) for different substances. Paired oral fluid and whole blood samples were collected from volunteers and persons suspected of drug use in four...
Conference Paper
Full-text available
Background The prevalence of drunk driving is low in Norway; only about 0.2% of car drivers have blood alcohol concentrations (BACs) above the legal limit of 0.02 g/dl. The prevalence of driving with concentrations of psychoactive drugs in blood above the legislative limits is estimated to be 1-2%. However, alcohol is still the most commonly found...
Conference Paper
Full-text available
Background Approximately 3.05 million motor vehicles are registered in Norway. Motorcycles and mopeds (MMs) represent 11% of the vehicles and 2% of the rides but as much as 21% of drivers killed in road traffic crashes. Aims To investigate the prevalence of alcohol and drugs above the legislative limits among MM riders killed in road traffic crashe...
Article
Objective: To examine alcohol and drug use among random drivers in different regions of Norway by analyzing oral fluid, compare drivers in urban and rural areas, compare with results from the roadside survey in southeastern Norway in 2005-2006, and roughly estimate the prevalence of driving with blood drug concentrations above the new Norwegian le...
Article
A feasibility study was performed to examine the effectiveness of hair testing in determining the prevalence of drug use in a young adult population. The study included 200 randomly selected young adults in Norway. It was designed to make the collection, preparation and analysis of the samples as little resource demaning as possible. Full anonymity...
Article
The aim of this study was to determine the association between alcohol or drug use with fatal injury in road traffic accidents by calculating odds ratios (ORs) using a case-control design. The ‘cases’ were 508 drivers killed in road traffic accidents in the period 2003–2010 from whom blood samples were sent to the Norwegian Institute of Public Heal...
Article
Full-text available
Our objective was to determine the presence of psychoactive substances in blood of drivers killed in road crashes in four European countries. Data from 1118 drivers of car and vans, killed between 2006 and 2009, were collected in Finland, Norway, Portugal and Sweden. The prevalence of any psychoactive substance ranged between 31 and 48%. Alcohol (≥...