Journal of forensic and legal medicine, Jan 26, 2016
Of all the drugs of forensic interest, none are more common or pervasive than alcohol. A thorough... more Of all the drugs of forensic interest, none are more common or pervasive than alcohol. A thorough understanding of all aspects of alcohol pharmacokinetics and pharmacodynamics is essential for any clinical forensic practitioner. In rare cases interpretation of blood alcohol results may require questions to be asked about laboratory analysis. We present a case where an apparently positive blood alcohol result could have resulted in an unnecessary avenue of coronial investigation of a child death.
Good vision is essential for safe driving and studies have associated visual impairment with an i... more Good vision is essential for safe driving and studies have associated visual impairment with an increased crash risk. Currently, there is little information about the medical review of drivers with visual field loss. This study examines the prevalence of visual field loss among drivers referred for medical review in one Australian jurisdiction and investigates factors associated with licence outcome in this group. A random sample of 10,000 (31.25 per cent) medical review cases was extracted for analysis from the Victorian licensing authority. Files were screened for the presence of six visual field-related medical conditions. Data were captured on a range of variables, including referral source, age, gender, health status, crash history and licence outcome. Prevalence analyses were univariate and descriptive. Logistic regression was used to assess factors associated with licence outcomes in the visual field loss group. Approximately 1.9 per cent of the 10,000 medical review cases screened had a visual field loss condition identified (n = 194). Among the visual field loss group, 57.2 per cent were permitted to continue driving (conditional/unconditional licence). Primary referral sources were the police, self-referrals and general medical practitioners. Key factors associated with licence test outcomes were visual field condition, age group, crash involvement and referral to the Driver Licensing Authority's Medical Advisors. Those who were younger had a crash involvement triggering referral and those who were referred to the Medical Advisors were more likely to have a positive licensing outcome. The evidence base for making licensing decisions is complicated by the variable causes, patterns, progressions and measuring technologies for visual field loss. This study highlighted that the involvement of an expert medical advisory service in Victoria resulted in an increased likelihood that drivers with visual field loss will be allowed to continue driving. Further research is warranted to explore issues relating to severity of field loss and the capacity for compensation.
An understanding of tetrahydrocannabinol (THC) kinetics and residual levels after cannabis use is... more An understanding of tetrahydrocannabinol (THC) kinetics and residual levels after cannabis use is essential in interpreting toxicology tests in body fluids from live subjects, particularly when used in forensic settings for drug abuse, traffic and interpersonal violence cases. However the current literature is largely based on laboratory studies using controlled cannabis dosages in experienced users, with limited research investigating the kinetics of residual THC concentrations in regular high dose cannabis users. Twenty-one dependent cannabis users were recruited at admission to two residential detoxification units in Melbourne, Australia. After being provided with information about, and consenting to, the study, subjects volunteered to provide once-daily blood, urine and oral fluid (saliva) samples for seven consecutive days following admission, involving cessation and abstinence from all cannabis use. Blood and oral fluid specimens were analysed for THC and urine specimens for t...
A range of medical conditions can lead to visual impairments either through effects on the eye or... more A range of medical conditions can lead to visual impairments either through effects on the eye or the visual pathways and brain. The prevalence of visual impairment increases with age. Furthermore, research evidence has shown that aging is related to a number of other processes that can lead to changes in cognitive functioning and sensory perception that may adversely affect driving (Marottoli and Drickamer, 1993; Stelmach and Nahom, 1992). This combination of factors is thought to contribute to older driver crash risk (Hakamies-Blomqvist, 1993; Stutts et al., 1998). Licensing authorities are the primary entity responsible for monitoring the medical fitness of their license holders. While it is important for licensing bodies to identify drivers who have conditions that place them at a heightened risk for crashes, at the same time, they should not unfairly restrict the mobility of disabled or aging drivers. Therefore, it is important that the licensing criteria for visual fitness to ...
To determine the drug use in injured Victorian drivers involved in motor vehicle collisions and s... more To determine the drug use in injured Victorian drivers involved in motor vehicle collisions and subsequently transported to a major adult trauma centre in Victoria. A blood sample was obtained from patients who had been taken to The Alfred Emergency & Trauma Centre (Prahran, Vic., Australia) following a motor vehicle collision. This was performed at the same time and under the same law as compulsory blood screening in Victoria (Section 56 of the Road Safety Act). Four hundred and thirty-six specimens were analysed. Blood stored in vacutainer tubes containing preservative were screened for drugs using enzyme-linked immunosorbent assay and gas chromatography-mass spectometry analysis. Medically administered drugs were excluded from the results. Four hundred and thirty-six specimens were analysed. Metabolites of cannabis were the most commonly found drug (46.7%), the active form of cannabis (Delta9-tetrahydrocannabinol) was found in 33 specimens (7.6%). The next most prevalent drugs were benzodiazepines (15.6%), opiates (11%), amphetamines (4.1%) and methadone (3%). Cocaine was detected in 1.4% of cases. Of the motor vehicle collisions 66% involved males and females of 15-44 years old and Delta9-tetrahydrocannabinol was almost exclusively found in this age group. In motor vehicle collisions involving older drivers there was an increasing use of benzodiazepines. In women >65 years old 30% were positive for benzodiazepines. Drug usage found in this group of injured drivers was disturbingly high. The introduction of further initiatives to decrease the prevalence of drug use in motor vehicle drivers is required.
ABSTRACT Background: The Occupational Therapy Driver Off Road Assessment (OT-DORA) Battery is in ... more ABSTRACT Background: The Occupational Therapy Driver Off Road Assessment (OT-DORA) Battery is in development as a comprehensive off-road evaluation of fitness to drive. Although several psychometric properties of the Road Law and Road Craft Test (RLRCT) have been previously studied, interrater reliability must also be established to include this test in the battery. Aim: The aim of the study was to determine the interrater reliability of the RLRCT. Method: Three occupational therapy driver assessors independently scored 20 client responses on the 14-item RLRCT. Results: The interrater reliability for all items, except item 6, was found to be between 0.57 and 1.00. The scoring instructions for item 6 were revised and the interrater reliability rose from 0.42 to 0.77. Conclusion: The RLRCT has been found to be reliable when administered by different raters and is thus suitable for inclusion in the OT-DORA Battery. Ongoing research to confirm the psychometric properties of the RLRCT is required.
The number of functionally impaired drivers being assessed is increasing the urgency to develop a... more The number of functionally impaired drivers being assessed is increasing the urgency to develop a standardized off-road driver assessment battery. We examined the validity of the Road Law and Road Craft Test (RLRCT) and a version of the Melbourne Slide Test to determine whether they should be included in the Occupational Therapy Driver Off-Road Assessment (OT-DORA) battery, which is under development. We conducted a file audit of 118 data sets with individual item scores for the RLRCT and Melbourne Slide Test. The RLRCT test with one item removed provides clinicians with a valid indication of clients' off-road driving skills. The Melbourne Slide Test added no new information over that provided by the RLRCT and can be excluded from the battery. The revised 14-item RLRCT should be included in the OT-DORA battery. Further research is required to develop the OT-DORA battery as a valid and reliable measure of off-road driver skill.
Journal of forensic and legal medicine, Jan 26, 2016
Of all the drugs of forensic interest, none are more common or pervasive than alcohol. A thorough... more Of all the drugs of forensic interest, none are more common or pervasive than alcohol. A thorough understanding of all aspects of alcohol pharmacokinetics and pharmacodynamics is essential for any clinical forensic practitioner. In rare cases interpretation of blood alcohol results may require questions to be asked about laboratory analysis. We present a case where an apparently positive blood alcohol result could have resulted in an unnecessary avenue of coronial investigation of a child death.
Good vision is essential for safe driving and studies have associated visual impairment with an i... more Good vision is essential for safe driving and studies have associated visual impairment with an increased crash risk. Currently, there is little information about the medical review of drivers with visual field loss. This study examines the prevalence of visual field loss among drivers referred for medical review in one Australian jurisdiction and investigates factors associated with licence outcome in this group. A random sample of 10,000 (31.25 per cent) medical review cases was extracted for analysis from the Victorian licensing authority. Files were screened for the presence of six visual field-related medical conditions. Data were captured on a range of variables, including referral source, age, gender, health status, crash history and licence outcome. Prevalence analyses were univariate and descriptive. Logistic regression was used to assess factors associated with licence outcomes in the visual field loss group. Approximately 1.9 per cent of the 10,000 medical review cases screened had a visual field loss condition identified (n = 194). Among the visual field loss group, 57.2 per cent were permitted to continue driving (conditional/unconditional licence). Primary referral sources were the police, self-referrals and general medical practitioners. Key factors associated with licence test outcomes were visual field condition, age group, crash involvement and referral to the Driver Licensing Authority's Medical Advisors. Those who were younger had a crash involvement triggering referral and those who were referred to the Medical Advisors were more likely to have a positive licensing outcome. The evidence base for making licensing decisions is complicated by the variable causes, patterns, progressions and measuring technologies for visual field loss. This study highlighted that the involvement of an expert medical advisory service in Victoria resulted in an increased likelihood that drivers with visual field loss will be allowed to continue driving. Further research is warranted to explore issues relating to severity of field loss and the capacity for compensation.
An understanding of tetrahydrocannabinol (THC) kinetics and residual levels after cannabis use is... more An understanding of tetrahydrocannabinol (THC) kinetics and residual levels after cannabis use is essential in interpreting toxicology tests in body fluids from live subjects, particularly when used in forensic settings for drug abuse, traffic and interpersonal violence cases. However the current literature is largely based on laboratory studies using controlled cannabis dosages in experienced users, with limited research investigating the kinetics of residual THC concentrations in regular high dose cannabis users. Twenty-one dependent cannabis users were recruited at admission to two residential detoxification units in Melbourne, Australia. After being provided with information about, and consenting to, the study, subjects volunteered to provide once-daily blood, urine and oral fluid (saliva) samples for seven consecutive days following admission, involving cessation and abstinence from all cannabis use. Blood and oral fluid specimens were analysed for THC and urine specimens for t...
A range of medical conditions can lead to visual impairments either through effects on the eye or... more A range of medical conditions can lead to visual impairments either through effects on the eye or the visual pathways and brain. The prevalence of visual impairment increases with age. Furthermore, research evidence has shown that aging is related to a number of other processes that can lead to changes in cognitive functioning and sensory perception that may adversely affect driving (Marottoli and Drickamer, 1993; Stelmach and Nahom, 1992). This combination of factors is thought to contribute to older driver crash risk (Hakamies-Blomqvist, 1993; Stutts et al., 1998). Licensing authorities are the primary entity responsible for monitoring the medical fitness of their license holders. While it is important for licensing bodies to identify drivers who have conditions that place them at a heightened risk for crashes, at the same time, they should not unfairly restrict the mobility of disabled or aging drivers. Therefore, it is important that the licensing criteria for visual fitness to ...
To determine the drug use in injured Victorian drivers involved in motor vehicle collisions and s... more To determine the drug use in injured Victorian drivers involved in motor vehicle collisions and subsequently transported to a major adult trauma centre in Victoria. A blood sample was obtained from patients who had been taken to The Alfred Emergency & Trauma Centre (Prahran, Vic., Australia) following a motor vehicle collision. This was performed at the same time and under the same law as compulsory blood screening in Victoria (Section 56 of the Road Safety Act). Four hundred and thirty-six specimens were analysed. Blood stored in vacutainer tubes containing preservative were screened for drugs using enzyme-linked immunosorbent assay and gas chromatography-mass spectometry analysis. Medically administered drugs were excluded from the results. Four hundred and thirty-six specimens were analysed. Metabolites of cannabis were the most commonly found drug (46.7%), the active form of cannabis (Delta9-tetrahydrocannabinol) was found in 33 specimens (7.6%). The next most prevalent drugs were benzodiazepines (15.6%), opiates (11%), amphetamines (4.1%) and methadone (3%). Cocaine was detected in 1.4% of cases. Of the motor vehicle collisions 66% involved males and females of 15-44 years old and Delta9-tetrahydrocannabinol was almost exclusively found in this age group. In motor vehicle collisions involving older drivers there was an increasing use of benzodiazepines. In women >65 years old 30% were positive for benzodiazepines. Drug usage found in this group of injured drivers was disturbingly high. The introduction of further initiatives to decrease the prevalence of drug use in motor vehicle drivers is required.
ABSTRACT Background: The Occupational Therapy Driver Off Road Assessment (OT-DORA) Battery is in ... more ABSTRACT Background: The Occupational Therapy Driver Off Road Assessment (OT-DORA) Battery is in development as a comprehensive off-road evaluation of fitness to drive. Although several psychometric properties of the Road Law and Road Craft Test (RLRCT) have been previously studied, interrater reliability must also be established to include this test in the battery. Aim: The aim of the study was to determine the interrater reliability of the RLRCT. Method: Three occupational therapy driver assessors independently scored 20 client responses on the 14-item RLRCT. Results: The interrater reliability for all items, except item 6, was found to be between 0.57 and 1.00. The scoring instructions for item 6 were revised and the interrater reliability rose from 0.42 to 0.77. Conclusion: The RLRCT has been found to be reliable when administered by different raters and is thus suitable for inclusion in the OT-DORA Battery. Ongoing research to confirm the psychometric properties of the RLRCT is required.
The number of functionally impaired drivers being assessed is increasing the urgency to develop a... more The number of functionally impaired drivers being assessed is increasing the urgency to develop a standardized off-road driver assessment battery. We examined the validity of the Road Law and Road Craft Test (RLRCT) and a version of the Melbourne Slide Test to determine whether they should be included in the Occupational Therapy Driver Off-Road Assessment (OT-DORA) battery, which is under development. We conducted a file audit of 118 data sets with individual item scores for the RLRCT and Melbourne Slide Test. The RLRCT test with one item removed provides clinicians with a valid indication of clients' off-road driving skills. The Melbourne Slide Test added no new information over that provided by the RLRCT and can be excluded from the battery. The revised 14-item RLRCT should be included in the OT-DORA battery. Further research is required to develop the OT-DORA battery as a valid and reliable measure of off-road driver skill.
Uploads