Standardized Field Sobriety Tests Research Articles

The horizontal ladder test (HLT) protocol: a novel, optimized, and reliable means of assessing motor coordination in Sus scrofa domesticus.

Pigs can be an important model for preclinical biological research, including neurological diseases such as Alcohol Use Disorder. Such research often involves longitudinal assessment of changes in motor coordination as the disease or disorder progresses. Current motor coordination tests in pigs are derived from behavioral assessments in rodents and lack critical aspects of face and construct validity. While such tests may permit for the comparison of experimental results to rodents, a lack of validation studies of such tests in the pig itself may preclude the drawing of meaningful conclusions. To address this knowledge gap, an apparatus modeled after a horizontally placed ladder and where the height of the rungs could be adjusted was developed. The protocol that was employed within the apparatus mimicked the walk and turn test of the human standardized field sobriety test. Here, five Sinclair miniature pigs were trained to cross the horizontally placed ladder, starting at a rung height of six inches and decreasing to three inches in one-inch increments. It was demonstrated that pigs can reliably learn to cross the ladder, with few errors, under baseline/unimpaired conditions. These animals were then involved in a voluntary consumption of ethanol study where animals were longitudinally evaluated for motor coordination changes at baseline, 2.5, 5, 7.5, and 10% ethanol concentrations subsequently to consuming ethanol. Consistent with our predictions, relative to baseline performance, motor incoordination increased as voluntary consumption of escalating concentrations of ethanol increased. Together these data highlight that the horizontal ladder test (HLT) test protocol is a novel, optimized and reliable test for evaluating motor coordination as well as changes in motor coordination in pigs.

Enhancing the Standardized Field Sobriety Test to detect cannabis impairment: An observational study

Objective The purpose of this study was to explore various tests of impairment that could potentially be added to the Standardized Field Sobriety Test (SFST) to enhance its sensitivity to identify drivers whose abilities are adversely affected by cannabis. Methods An observational study was conducted in which participants were invited to use their own cannabis at the research facility. Once prior to cannabis use and at four times during the 150 min after cannabis use, participants performed the three tests of the Standardized Field Sobriety Test (SFST) (i.e., Horizontal Gaze Nystagmus, Walk and Turn, and One Leg Stand) as well as the Modified Romberg Balance and Finger to Nose tests. In addition, assessments were made of physiological indicators (i.e., eyelid, leg and body tremors, rebound dilation, lack of convergence) and vital signs (pulse, blood pressure and body temperature). Participants also completed a digit-symbol substitution task at each testing interval. With the exception of vital signs and the digit symbol task, all tests and assessments were administered and scored by certified Drug Recognition Experts using the standard procedures of the Drug Evaluation and Classification Program. Results Twenty minutes after vaping cannabis (mean THC concentration = 6.34 ng/mL), participants displayed performance deficits on a variety of tasks; 67% met the criterion for suspected impairment on the SFST. Addition of the Finger-to-Nose (FTN) test along with observations of head movements and jerks (HMJ) increased the percentage of participants who met the criterion for suspected impairment by 33% and improved the sensitivity of the test from 0.67 to 0.88. Conclusions The results of this study support supplementing the SFST with the Finger-to-Nose test and observations of HMJ to assist in the detection of drivers who are adversely affected by the use of cannabis. The observational study design and the use of assessors who were not blinded as to the use of cannabis by participants limits the strength of the evidence. Further research, including randomized trials and field studies of drivers, is required to confirm and validate this enhanced version of the SFST.

The Impact of Vaping Ethanol-Containing Electronic Cigarette Liquids on Roadside Impairment Investigations.

Legal professionals and others have suggested that vaping electronic cigarettes (e-cigs) prior to or during ethanol breath testing may produce false positives. Preliminary Breath Tests (PBTs) and Evidentiary Breath Tests (EBTs) measure ethanol in exhaled breath, and Standardized Field Sobriety Tests (SFSTs) are used to assess impairment. Ethanol has been identified in e-cig liquids (e-liquids). Presented are a series of experiments designed to determine the mechanics of vaping ethanol using an e-cig, and the effects of vaping ethanol on the SFSTs and breath tests used by law enforcement officers (LEO). Twelve participants (5 females, age: 21-32 and 7 males, age: 21-55), vaped either one or ten puffs of an e-liquid (0% or 20% ethanol). LEOs assessed impairment using SFSTs (12 and 42 min), PBTs (<1, 27, 32, 37, and 57 min), and EBTs (2, 29, 34, 39 and 59 min) post vaping. A self-assessment test was administered post vaping (22 and 52 min). Baseline responses for all measures were collected prior to vaping. Results demonstrated that ethanol in the e-liquids was aerosolized by e-cigs, and produced particles that could reach the deep lung tissue based on mean-mass diameter. Ethanol was detected by PBT <3 minutes after participants vaped one (0.007-0.030 g/210L) or 10 puffs (013-0.074 g/210 L) of a 20% ethanol e-liquid. Ethanol was not detected by PBT at any subsequent timepoint. Ethanol was not detected by the EBT under any condition. Impairment was not indicated by the SFST. Some subjective effects were reported, but few statistically significant differences between conditions were indicated. A wait period prior to ethanol breath testing is not always mandated, depending on jurisdiction, or observed in all applications, such as workplace testing. The results demonstrate that a wait period must be employed to prevent vaping-related false positive breath ethanol results.

Increasing Prevalence of Designer Benzodiazepines in Impaired Driving; a 5 Year Analysis from 2017-2021.

Designer benzodiazepine (DBZD) use has been increasing over the past decade and poses a threat to human health and safety, particularly when involved in driving under the influence of drugs (DUID) cases. Over a five-year period between 2017 and 2021, there were 1145 reported DBZDs in 805 blood samples submitted from law enforcement agencies for DUID testing. Eleven different DBZD were detected, including three metabolite pairs: etizolam/alpha-hydroxyetizolam, clonazolam/8-aminoclonazolam, diclazepam/delorazepam, flualprazolam, flubromazolam, flubromazepam, bromazolam, and bromazepam. Etizolam/alpha hydroxyetizolam (n=485) and flualprazolam (n=149) were the most frequently detected DBZD, at 60% and 18%, respectively. Driving behavior, standardized field sobriety tests (SFST) performance, and physical observations of individuals suspected of DUID, whose blood was toxicologically confirmed for one or more DBZD, were consistent with effects caused by central nervous system (CNS) depressants. Each DBZD has its own unique timeline, and toxicology testing had to be frequently updated to reflect the state of the novel psychoactive substance (NPS) market. DBZD play a role in impaired driving and can be the sole intoxicant in DUID cases.

Impact of vaping ethanol on the roadside field sobriety test in a clinical setting

Recent studies have shown that electronic cigarette (e-cig) liquid formulations (e-liquids) can contain ethanol, sometimes in concentrations greater than 20%. Ethanol, rarely listed as an ingredient in e-liquids, is often used as a thinning agent, to dissolve insoluble substances, or added intentionally for consumption. Ethanol in e-liquids has been demonstrated to be aerosolized by e-cigs. Ethanol within the aerosol can be absorbed across mucosal membranes in the mouth, and also within deep lung tissue based on mean-mass particle size diameter. Preliminary Breath Tests (PBT) and Evidentiary Breath Tests (EBT) are conducted to measure ethanol in exhaled breath, with a 15–20 minute wait period, and Standardized Field Sobriety Tests (SFST) evaluate several operant conditions to assess ethanol impairment. Literature on impacts of vaping ethanol is limited. An evaluation to assess the impact of vaping ethanol from e-liquids is essential for law enforcement officers (LEO), medical review officers, ethanol treatment and recovery providers, workplace drug testing, and court mandated drug testing. This study evaluated the impact of inhaled ethanol via vaping on the SFST, PBT, and EBT for thirteen participants using a blind two-by-two experimental design under Virginia Commonwealth University (VCU) IRB HM20015064 and in collaboration with the Virginia Department of Forensic Science, the Center for the Study of Tobacco Products at VCU, VCU Police Department, and City of Richmond Police Department. E-liquids were made by a commercial manufacturer at concentrations of 0% and 20% ethanol. Ethanol concentrations were verified in-house using a Shimadzu HS-20 headspace attached to a Nexis GC-2030 gas chromatograph with dual flame ionization detectors. Stability studies were performed monthly to ensure sample suitability prior to clinical use. Thirteen participants were enrolled into the study based on inclusion and exclusion criteria. They vaped either one or ten puffs of an e-liquid (0% or 20% ethanol). LEOs assessed indicators of impairment by following a study design incorporating SFSTs, PBTs, and EBTs at predetermined intervals. Ethanol concentrations within the e-liquids were determined to be stable at −20 °C for the duration of the study. Positive breath ethanol results ranged from 0.007–0.030 and 0.013–0.043 g/210 dL by PBT immediately after using a 20% ethanol e-liquid when vaping one-puff and ten-puffs, respectively. All subsequent PBTs were negative for ethanol. No ethanol or instrument error was detected by EBT for any vaping scenario, at any timepoint. Impairment was not indicated by SFST. A well-designed human clinical study with robust and relevant collaborations between a crime lab, police departments, and a research university is important to address pertinent questions to forensic science. Breath ethanol concentrations were detectable by PBT immediately after vaping an e-liquid containing 20% ethanol. The results demonstrated the standard wait period of 15–20 minutes employed by LEO before administering a PBT for roadside stops was effective in negating vaping-related false positive breath ethanol results. Vaping ethanol also did not impact SFST results. Results should be considered for other contexts of ethanol testing, such as workplace testing and vehicle ignition interlock systems.

Would CNS depressants cause paradoxical aggressive driving behaviors?

Aggressive driving consists of risky driving behaviors and traffic infractions performed with ill intent or disregard for other road users’ safety and associated with negative emotions like anger and frustration. Such behaviors may include tailgating, speeding, weaving through traffic, running red lights, and others. While evaluating the risk of drugs that decrease inhibitions or have central nervous system (CNS) stimulant effects like alcohol and cocaine for aggressive driving behaviors makes sense, doing the same with benzodiazepines and other CNS depressants may appear illogical since the drugs would have anti-aggressive effects, inducing sedation and stabilizing mood. However, unexpected aggressive/agitated episodes, albeit rarely, have been reported after the use of certain CNS depressants. The purpose of this study is to evaluate whether CNS depressants may lead to paradoxical aggressive driving behaviors by reviewing case reports of suspected impaired drivers tested positive for CNS depressants other than ethanol. This research examined driving while intoxicated (DWI) or under the influence of drugs (DUID) cases submitted in 2019 and tested positive in blood for CNS depressants other than ethanol only (i.e., benzodiazepines, barbiturates, muscle relaxants, antipsychotics, and anticonvulsants). The blood samples were submitted by the Houston Police Department and were subsequently analyzed for alcohol and drugs by Houston Forensic Science Center and a reference laboratory. Toxicological findings, demographic information as well as driving behaviors and the standardized field sobriety test (SFST) observations of impairment described in the police reports were evaluated. Among 1214 DWI/DUID cases in which offense occurred in 2019 and blood samples were tested positive for one or more drugs, just 50 drivers were tested positive for CNS depressants only. Twenty-five drugs/metabolites were identified with benzodiazepines/metabolites being the most prevalent, in 72% of the 50 cases. The majority exhibited typical behaviors expected from CNS depressant use: 86% of the drivers had non-violent attitudes and 91% (39/43) showed horizontal gaze nystagmus (HGN). All ( n = 35) showed one or more clues in Walk and Turn (WAT) and except 2, in One-leg Stand (OLS). Traffic incidents included weaving (22%), hitting an object or another vehicle (38%), stopping in a moving lane (18%). However, a few drivers exhibited agitation. Below are two case examples: – case 1: 58-year-old female driver failed to signal a lane change, accelerating away from the patrol car and yelling. When officers encountered the driver, she exhibited uncooperative and erratic behaviors. Officer could only administer HGN, and she showed 2/6 clues. Blood sample was positive for alprazolam at 13 ng/mL and meprobamate at 2.5 μg/mL; – case 2: 24-year-old female driver stopped in a moving lane of traffic. Upon officers approaching the vehicle, she began to speak to officers in an agitated voice. Officers observed the driver could not keep balance. SFST results included 4/6 HGN, 3/4 OLS, and 6/8 WAT clues. Blood sample was positive for alprazolam at 120 ng/mL and for zolpidem at 100 ng/mL; Considering a multitude of social, environmental, and biological factors that can influence one's driving performance, the findings should be taken with caution and alternative interpretations other than drug effects should be considered. The research confirmed that aggressive behaviors among CNS depressant positive drivers are rare and idiosyncratic. These case examples nonetheless demonstrated how different drugged driving behaviors can be and more research is needed to further clarify the association.

The high reported accuracy of the standardized field sobriety test is a property of the statistic not of the test

Abstract OBJECTIVE In the 1990s as the legal blood alcohol limit for driving changed, validation studies reported the Standardized Field Sobriety Test (SFST) to be accurate at discriminating between Blood Alcohol Concentrations (BAC) above or below several legal limits: 0.10, 0.08, 0.05 and 0.04%. We investigated the contribution of the validation studies’ choice of accuracy statistic to the SFST’s reported accuracy. METHODS Using the data set from a commonly cited SFST validation study, we calculated the arrest accuracy and overall accuracy of the SFST at identifying BACs above or below 31 different target BACs from 0.00 to 0.30%. RESULTS At target BAC 0.30% the arrest accuracy of the SFST is 1%; at BAC 0.15%, 34%; at BAC 0.00%, 100%. The statistics arrest accuracy and overall accuracy describe the SFST, a test designed to identify changes caused by alcohol, as less accurate when the changes are severe, more accurate when changes are mild, and as 100% (arrest) and 93% (overall) accurate when there are no changes at all. CONCLUSION The statistics overall accuracy and arrest accuracy to not quantify the probability that impaired driving defendants who failed the SFST had an elevated BAC or were impaired.

Impairment Screening Utilizing Biophysical Measurements and Machine Learning Algorithms.

Drug recognition expert (DRE) officers employ a set of tests to investigate drivers who are under impairment and to determine the type of drug that they have used. Horizontal Gaze Nystagmus (HGN), Walk and Turn (WAT), and One Leg Stand (OLS) are the main three tests included in the Standardized Field Sobriety Tests (SFSTs), which lead the officers to evaluate the sobriety of drivers. Performing these tests requires trained officers, but the final decision may still be subjective. These tests along with a suite of comprehensive (yet manual) at-station testing are the basis of police decision making and are subjected to scrutiny by courts. Therefore, designing an automated system to detect impairment not only will help officers in making accurate decisions, but also will remove the subjectivity and can potentially serve as a court-admissible evidence. In this paper, a new method for automated impairment detection is introduced and implemented using data analysis and machine learning algorithms based on a comprehensive suite of tests performed on 34 participants.

Buprenorphine Prevalence in DUID Cases in Southwestern Virginia: Case Studies and Observations.

Buprenorphine, a semisynthetic mixed agonist/antagonist opioid used primarily for the treatment of opioid use disorder, was reported in 194 driving under the influence of drugs (DUID) cases in Southwestern Virginia during the period from 2017 through 2019. Identifying and confirming buprenorphine in DUID cases is common in this region. Interpretation is complex due to the large range of concentrations of buprenorphine found in blood and frequent combinations with other therapeutic and abused drugs. Buprenorphine was identified by immunoassay and quantified by liquid chromatography-tandem mass spectrometry. A sensitive method was necessary as one-third of concentrations of buprenorphine and/or norbuprenorphine were <1.0 µg/L. Concentrations of buprenorphine ranged from <0.5 to 11 µg/L (mean 2.5 µg/L, median 1.8 µg/L) and concentrations of norbuprenorphine ranged from <0.5 to >20 µg/L (mean 3.3 µg/L, median 2.2 µg/L). Buprenorphine polysubstance use was common. Only 10% of the cases examined did not contain other drugs confirmed in routine DUID screening tests. The most common drug groups confirmed were benzodiazepines, amphetamines and cannabinoids. The DUID case histories presented represent examples of buprenorphine abuse, buprenorphine with no other drug groups, buprenorphine combined with other drug groups, cases consistent with impairment and cases with minimal impairment. Central nervous system depressant and narcotic analgesic symptoms were commonly observed; however, some cases contained stimulant symptoms. Buprenorphine-to-norbuprenorphine (B/NB) ratios had a mean and median ratio of 1.1 and 0.8, respectively. B/NB ratios >3.0 were found in 4.7% of the cases. The finding of a higher B/NB ratio may indicate a more recent buprenorphine administration and a greater potential for impairment. No relationship between the concentration of buprenorphine and/or norbuprenorphine in blood and the performance on drug recognition expert evaluation or standardized field sobriety tests could be determined.

Automated assessment of alcohol-induced impairment of balance in male and female social drinkers.

The acute administration of alcohol reliably impairs the ability to balance when standing. The standardized field sobriety test uses alcohol-induced impairment of body stability to indicate probable alcohol intoxication. Given that body sway is used in the detection of alcohol impairment and intoxication, it is surprising that little research with humans has incorporated new technology that provides automated neuromuscular control assessment. Therefore, the purpose of this study was to examine the dose response to the acute effects of alcohol below and at the legal limit for driving in the United States on balance impairments, as measured by the Biosway Portable Balance System (Biodex Medical Systems, Inc.). Fourteen social drinkers attended 3 separate sessions during which they received alcohol (0.0, 0.3, and 0.6 g/kg alcohol). Body sway with eyes open and eyes closed was assessed at 45 min after dose administration when breath alcohol concentration was peaking for both active alcohol doses (.04g% and .08g%). The results indicated that body sway was significantly increased in the 0.6 g/kg alcohol conditions when compared with the placebo and 0.3 g/kg alcohol conditions. Body sway was not significantly elevated in the 0.3 g/kg alcohol condition compared with placebo. The results from this study suggest that this new technology may be of interest to alcohol researchers and the police as a more precise assessment of balance. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Bupenorphine in Wisconsin Drivers: Concerns for Impairment?

Opinions vary on whether buprenorphine can cause impairment in drivers. Relatively little information on the observed effects of buprenorphine, outside a laboratory or a controlled driving course, exist in the literature. The Wisconsin State Laboratory of Hygiene monitored the detection of buprenorphine and its pharmacologically active metabolite, norbuprenorphine (NBUP), in Wisconsin drivers over a 2-year period. A total of 204 individuals (78 females and 126 males) were driving under the influence of buprenorphine and/or NBUP. Concentrations in whole blood (ng/mL) ranged (mean) from 0.6 to 14 (2.0) and 0.5 to 20 (2.1) for buprenorphine and NBUP, respectively. Poly-substance use is extremely prevalent in Wisconsin operating while intoxicated casework, so prevalent that only four of the previously described cases had buprenorphine and/or NBUP as the only drug(s) detected. This paper summarizes and highlights the case histories and observed impairments of those four cases. Law enforcement (LE) made contact with three of the four subjects due to either a crash or poor/reckless driving. Police reports and observations made by LE, including drug recognition expert (DRE) evaluations, were collected. Physical and behavioral observations made by LE varied and included a combination of narcotic analgesic, central nervous system depressant- and stimulant-like effects. Impaired balance and lack of coordination during the administration of the Standardized Field Sobriety Tests were documented by the arresting officers and/or the DRE. While the number of buprenorphine-only cases reported here is limited, the results demonstrate the complex paradigm associated with forensic interpretation of buprenorphine in driving under the influence of drugs casework and the frequency of poly-substance administration in Wisconsin drivers.

On Smartphone Sensability of Bi-Phasic User Intoxication Levels from Diverse Walk Types in Standardized Field Sobriety Tests.

Intoxicated driving causes 10,000 deaths annually. Smartphone sensing of user gait (walk) to identify intoxicated users in order to prevent drunk driving, have recently emerged. Such systems gather motion sensor (accelerometer and gyroscope) data from the users' smartphone as they walk and classify them using machine or deep learning. Standard Field Sobriety Tests (SFSTs) involve various types of walks designed to cause an intoxicated person to lose their balance. However, SFSTs were designed to make intoxication apparent to a trained law enforcement officer who manually proctors them. No prior work has explored which types of walk yields the most accurate results when assessed autonomously by a smartphone intoxicated gait assessment system. In this paper, we compare how accurately Long Short Term Memory (LSTM), Convolution Neural Network (CNN), Random Forest, Gradient Boosted Machines (GBM) and neural network classifiers are able to detect intoxication levels of drunk subjects who performed normal, walk-and-turn and standing on one foot SFST walks. We also compared the accuracy of intoxication detection on the ascending (increasing intoxication) vs descending (decreasing intoxication) limbs of drinking sessions (bi-phasic). We found smartphone intoxication sensing more accurate on the descending limb of the drinking episode and that intoxication detection on the normal walks of subjects were just as accurate as the SFSTs.

Effects of chronic marijuana use on driving performance

Objectives: The effects of marijuana on driving pose a significant public health concern. More studies on chronic marijuana use in driving are needed. The study objectives were to (1) assess differences in the Standardized Field Sobriety Test (SFST) and driving performance outcomes between chronic medical marijuana users and nonusers and (2) identify a cutoff tetrahydrocannabinol (THC) concentration above which chronic medical marijuana users demonstrate driving impairment.Methods: This prospective cross-sectional study assessed 31 chronic marijuana users and 41 nonusers. Rapid Detect Saliva Drug Screen 10-panel was administered to all participants. Participants were given a simple visual reaction time test (SVRT) and SFST consisting of the horizontal gaze nystagmus (HGN), the one leg stand (OLS), and the walk and turn (WAT) tests. The STISIM Drive M100 driving simulator assessed driving performance. Driving parameters included standard deviation of speed (SDS), deviation of mean lane position, off-road accidents, collisions, pedestrians hit, and car-following modulus, delay, and coherence. Cannabinoid blood plasma was obtained from marijuana users.Results: Marijuana users and nonusers did not differ in age (40.06 ± 13.92 vs. 41.53 ± 15.49, P = .6782). Marijuana users were more likely to fail the SFST (P = .005) and the WAT (P = .012) and HGN (P = .001) components. Marijuana users had slower SVRT (P = .031), less SDS (P = .039), and lower modulus (P = .003). Participants with THC >2 ng/mL (P = .017) and TCH >5 ng/mL (P = .008) had lower SDS. Participants with THC >2 ng/mL (P = .021) and THC >5 ng/mL (P = .044) had decreased modulus.Conclusion: Chronic marijuana users had slower reaction times, deviated less in speed, and had difficulty matching a lead vehicle’s speed compared to nonusers. The effects on SDS and modulus were present at cutoffs of 2 and 5 ng/mL.

The effects of breath alcohol concentration on postural control

ABSTRACTBackground: Two of the 3 standardized field sobriety tests that U.S. law enforcement uses at roadside checks have a postural equilibrium component to them. Those tests have been validated to detect impairment caused by blood alcohol concentrations (BACs) of 0.08 g/dL or above. Many medical and traffic safety associations support a lower limit, and one state, Utah, has passed a law to lower the limit to 0.05 g/dL. Many studies have examined the effects of alcohol on postural control (of which postural equilibrium is a component), with a consensus emerging that impairment is usually found at BACs greater than 0.06 g/dL. Most of these studies, however, had a relatively small number of subjects, usually between 10 and 30. The current study collected data from a much larger sample.Objective: The objective of this study was to provide additional evidence that posture control is negatively affected at BACs greater than 0.06 g/dL or breath alcohol concentrations (BrACs) of 0.06 g/210 L.Method: This was a between-subjects study, with BrAC group as the independent variable (5 levels: 0.00, 0.04, 0.06, 0.08, and 0.10 g/210 L); 4 measures of postural control as the dependent variables; and age, height, and weight as the covariates. Posture control was measured with a force-sensing platform connected to a computer. The feet's center of pressure (CoP) on the platform was recorded and the corresponding movement of the body in the anterior–posterior and lateral planes was derived. Participants (N = 96) were randomly assigned to one of the BrAC groups. Positive BrAC groups were compared to the zero BrAC group. Data were examined with hierarchical multiple regression.Results: Adjusted for age, height, and weight, the main effect of lateral CoP with eyes open was not statistically significant. There was a statistically significant main effect of alcohol on anterior–posterior CoP excursion with eyes open and with eyes closed and lateral CoP excursion with eyes closed. For all 3 of those variables, only BrACs of 0.08 and 0.10 g/210 L produced differences against zero BrAC. Although the main effect of alcohol on Lateral CoP Excursion with eyes open was not statistically significant, the contrasts between 0 and 0.08 and 0 and 0.10 g/210L BrAC were in the hypothesized direction.Conclusion: The current study did not directly address the issue of whether the sobriety tests are sensitive to BrACs of 0.05 g/210 L or above; rather, it provides additional evidence that postural control, one of the components of those tests, is relatively unaffected by BrACs lower than 0.08 g/210 L. Additional research is needed on the diagnostic characteristics of the sobriety tests at BrACs lower than 0.08 g/210 L.

Effects of caffeinated alcoholic beverages with low alcohol and high caffeine content on cognitive and motor functions.

In Taiwan, caffeinated alcoholic beverages (CABs), with high caffeine but low alcohol concentrations compared to those sold in Western countries, are commonly consumed at work and have been associated with work-related injuries. However, the effects on cognitive and motor functions and self-perception have not been examined. Twenty-eight healthy male volunteers (mean age: 32.6±2.7) participated in the study. Each participant visited our laboratory 4 times at intervals of at least 1week and was assigned to one of 4 trials in a counterbalanced order at each visit: placebo, alcohol, caffeinated energy drink, and CAB. They completed the subjective perception ratings, go/no-go tasks, Stroop color-word tests, Purdue pegboard tests, and the standardized field sobriety test. We used analysis of variance to examine the intraindividual differences in the performance. Consuming alcohol of 0.23g/kg typically consumed by Taiwanese CAB drinkers caused significant impairments in fine and crude motor functions; caffeine (1.5mg/kg) did not antagonize these effects but led to an improvement in response speed in the go/no-go task. The subjective perceptions produced by alcohol were not masked by caffeine. CABs that contains a higher ratio of caffeine to alcohol did not counteract the motor function impairments induced by alcohol.

Drugged Driving: How the Legalization of Marijuana Has Impaired the Ability of the Louisiana DWI Law

Marijuana is now legal in four states and the District of Columbia for recreational purposes and in 23 states and the District of Columbia for medicinal purposes. Effective August 1, 2016, Louisiana enacted drastic changes to its medical marijuana law, largely widening the scope of persons who will qualify for a medical marijuana prescription and beginning the process of establishing pharmaceutical requirements for the prescribed drug. Louisiana’s Driving While Intoxicated (DWI) law, Louisiana Revised Statutes § 14:98, which includes drugged driving, is effect-based, meaning it requires proof of impairment that was caused by a proscribed scheduled drug. Currently, proof of the presence of the inactive, non-impairing marijuana metabolite in a driver’s body is used as evidence of causation of marijuana impairment. Science simply does not support this presumption of causation as this metabolite can remain in the person’s body for over a month after ingestion and long after the effect of the marijuana has ceased. Additionally, most police officers are not specifically trained to detect drug impairment, as it manifests itself differently than alcohol impairment, and Standardized Field Sobriety Test (SFST) results should be challenged on the basis of relevancy. Other states have drafted zero-tolerance driving-under-the-influence (DUI) laws regarding drugged driving. Such laws require that the chemical test show the presence of the active, impairing marijuana metabolite in the driver’s blood. Case law has also carved out affirmative defenses protecting users of medical marijuana from the zero-tolerance laws. It is the author’s opinion that as marijuana becomes more prevalent in Louisiana, the effect-based law will become exposed as drastically ineffective. Therefore, this comment proposes an alternative law regarding driving under the influence of marijuana that is based on current specific scientific findings, also compensating for the lack of police officers’ ability to properly detect marijuana impairment.

Developing a standardized measurement of alcohol intoxication

IntroductionWe assessed multiple examinations and assessment tools to develop a standardized measurement of alcohol intoxication to aid medical decision making in the Emergency Department. MethodsVolunteers underwent an alcohol challenge. Pre- and post-alcohol challenge, subjects were videotaped performing three standardized clinical examinations: (1) Standardized Field Sobriety Test (SFST) examination, (2) Hack's Impairment Index (HII) examination, and (3) Cincinnati Intoxication Examination (CIE). Emergency clinicians evaluated the level of intoxication using five standardized assessment tools in a blinded and randomized fashion: (1) SFST assessment tool (range 0–18), (2) HII assessment tool (range 0–1), (3) St. Elizabeth Alcohol Intoxication Scale (STE, range 0–17), (4) a Visual Analog Scale (VAS, range 0–100), and (5) a Binary Intoxication Question (BIQ). Construct validity was assessed along with inter- and intra-rater reliability. ResultsMedian scores pre- and post-alcohol challenge were: SFST 6 (interquartile range 5) and 11 (3), respectively; HII 0 (0.05), 0.1 (0.1); STE 0 (1), 1 (2); VAS 10 (22), 33 (31). For BIQ, 59% and 91% indicated intoxication, respectively. Inter-rater reliability scores were: SFST 0.71 (95% confidence interval 0.48–0.86) to 0.93 (0.88–0.97) depending on examination component; HII 0.90 (0.82–0.95); STE 0.86 (0.75–0.93); VAS 0.92 (0.88–0.94); BIQ 0.3. Intra-rater reliability scores were: SFST 0.74 (0.64–0.82) to 0.87 (0.81–0.91); HII 0.85 (0.79–0.90); STE 0.78 (0.68–0.85); VAS 0.82 (0.74–0.87); BIQ 0.71. VAS reliability was best when paired with the HII and SFST examinations. ConclusionsHII examination, paired with either a VAS or HII assessment tool, yielded valid and reliable measurements of alcohol intoxication.

The Standardized Field Sobriety Tests (SFST) and measures of cognitive functioning

ObjectiveThe Standardized Field Sobriety Tests (SFST) are utilised widely to assess fitness to drive when law enforcement suspects a driver's ability to drive is impaired, whether by drugs or alcohol. The SFST ostensibly achieve this through assessment of the level of drivers’ cognitive and psychomotor impairment, although no studies have explicitly assessed the relatedness of cognitive ability and performance on the SFST. The current study aimed to assess the relationship between the three components of the SFST with a well validated computerised cognitive battery. MethodA sub-set of 61 placebo condition participants comprised the sample, with 33 females and 28 males (mean age 25.45 years). Correlations between the individual SFST subscales ‘Horizontal Gaze Nystagmus’ (HGN), the ‘One Leg Stand’ (OLS) and the ‘Walk and Turn’ test (WAT) and Cognitive Drug Research (CDR) sub-scales of ‘Quality of Working Memory’, ‘Power of Attention’ and ‘Continuity of Attention’ were analysed using point-biserial correlation. ResultsSixty participants were included for analyses. A weak–moderate positive (five subscales) and a moderate–strong negative (two subscales) association was noted between seven of the nine individual CDR subscales and the SFST subscale of the WAT test (all p<0.05). Individually, a moderate positive association was noted between the sub-scale ‘Nystagmus lack of smooth pursuit’ and ‘digit vigilance reaction time’ and ‘choice reaction time; reaction time’ (both p<0.05) and ‘Nystagmus head move and/or jerk’ and ‘simple reaction time’ (p<0.001). When assessed as a partially composite factor, a comparable association was also noted between the composite score of the SFST subscale ‘Nystagmus head move and/or jerk’ and both (a) simple and (b) digit vigilance reaction time (both p<0.05). No association was noted between any of the individual cognitive variables and the SFST subscale ‘OLS’, or between composite cognitive scores ‘Quality of Working Memory’, ‘Power of Attention’ and ‘Continuity of Attention’ and total SFST scores. DiscussionVariation in some aspects of cognitive performance was found to be moderately and positively correlated with some individual aspects of the SFST; particularly among tasks which assess reaction time. Impairment of these cognitive processes can also contribute to the completion of complex tasks such as driving or the SFST. Complex behavioural tasks such as driving are often severely impaired due to intoxication, and thus in a practical sense, the SFST can still be considered a useful screening tool to identify drug or alcohol impaired drivers.

The Effects of Dextromethorphan on Driving Performance and the Standardized Field Sobriety Test.

Dextromethorphan (DXM) is abused most commonly among adolescents as a recreational drug to generate a dissociative experience. The objective of the study was to assess driving with and without DXM ingestion. The effects of one-time maximum daily doses of DXM 120 mg versus a guaifenesin 400 mg dose were compared among 40 healthy subjects using a crossover design. Subjects' ability to drive was assessed by their performance in a driving simulator (STISIM® Drive driving simulator software) and by conducting a standardized field sobriety test (SFST) administered 1-h postdrug administration. The one-time dose of DXM 120 mg did not demonstrate driving impairment on the STISIM® Drive driving simulator or increase SFST failures compared to guaifenesin 400 mg. Doses greater than the currently recommended maximum daily dose of 120 mg are necessary to perturb driving behavior.

XLR-11 and UR-144 in Washington state and state of Alaska driving cases.

The case reports for 18 driving cases positive for the synthetic cannabinoid substances XLR-11 and/or UR-144 are discussed. Eleven of these cases had drug recognition expert evaluations performed. Slurred speech, lack of convergence and body and eyelid tremors were the most consistently noted interview characteristic. Pulse and blood pressure of the subjects were within the expected range. Most of the drivers contacted demonstrated poor driving; however, their performance on the standardized field sobriety tests yielded inconsistent diagnostic information. All cases were negative for other commonly detected drugs that affect the central nervous system, although one case was additionally positive for other synthetic cannabinoids. Of the studied cases, six were positive for only UR-144, whereas eight contained only XLR-11. Four cases were found to have both.