***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The driving performance is easily impaired as a consequence of the use of alcohol and /or licit and illicit drugs . However , the role of drugs other than alcohol in motor vehicle accidents has not been well established . The objective of this study was to estimate the association between psychoactive drug use and motor vehicle accidents requiring hospitalisation . A prospect i ve observational case-control study was conducted in the Tilburg region of The Netherl and s from May 2000 to August 2001 . Cases were car or van drivers involved in road crashes needing hospitalisation . Demographic and trauma related data was collected from hospital and ambulance records . Urine and /or blood sample s were collected on admission . Controls were drivers recruited at r and om while driving on public roads . Sampling was conducted by research ers , in close collaboration with the Tilburg police , covering different days of the week and times of the day . Respondents were interviewed and asked for a urine sample . If no urine sample could be collected , a blood sample was requested . All blood and urine sample s were tested for alcohol and a number of licit and illicit drugs . The main outcome measures were odds ratios ( OR ) for injury crash associated with single or multiple use of several drugs by drivers . The risk for road trauma was increased for single use of benzodiazepines ( adjusted OR 5.1 ( 95 % Cl : 1.8 - 14.0 ) ) and alcohol ( blood alcohol concentrations of 0.50 - 0.79 g/l , adjusted OR 5.5 ( 95 % Cl : 1.3 - 23.2 ) and > or=0.8 g/l , adjusted OR 15.5 ( 95 % Cl : 7.1 - 33.9 ) ) . High relative risks were estimated for drivers using combinations of drugs ( adjusted OR 6.1 ( 95 % Cl : 2.6 - 14.1 ) ) and those using a combination of drugs and alcohol ( OR 112.2 ( 95 % Cl : 14.1 - 892 ) ) . Increased risks , although not statistically significantly , were assessed for drivers using amphetamines , cocaine , or opiates . No increased risk for road trauma was found for drivers exposed to cannabis . The study concludes that drug use , especially alcohol , benzodiazepines and multiple drug use and drug-alcohol combinations , among vehicle drivers increases the risk for a road trauma accident requiring hospitalisation There were 13,176 roadside drug tests performed in the first year of the r and om drug-testing program conducted in the state of Victoria . Drugs targeted in the testing were methamphetamines and Delta(9)-tetrahydrocannabinol ( THC ) . On-site screening was conducted by the police using DrugWipe , while the driver was still in the vehicle and if positive , a second test on collected oral fluid , using the Rapiscan , was performed in a specially outfitted " drug bus " located adjacent to the testing area . Oral fluid on presumptive positive cases was sent to the laboratory for confirmation with limits of quantification of 5 , 5 , and 2 ng/mL for methamphetamine ( MA ) , methylenedioxy-methamphetamine ( MDMA ) , and THC , respectively . Recovery experiments conducted in the laboratory showed quantitative recovery of analytes from the collector . When oral fluid could not be collected , blood was taken from the driver and sent to the laboratory for confirmation . These roadside tests gave 313 positive cases following GC-MS confirmation . These comprised 269 , 118 , and 87 cases positive to MA , MDMA , and THC , respectively . The median oral concentrations ( undiluted ) of MA , MDMA , and THC was 1136 , 2724 , and 81 ng/mL. The overall drug positive rate was 2.4 % of the screened population . This rate was highest in drivers of cars ( 2.8 % ) . The average age of drivers detected with a positive drug reading was 28 years . Large vehicle ( trucks over 4.5 t ) drivers were older ; on average at 38 years . Females accounted for 19 % of all positives , although none of the positive truck drivers were female . There was one false positive to cannabis when the results of both on-site devices were considered and four to methamphetamines Background A significant proportion of road traffic crashes are attributable to alcohol and marijuana use while driving globally . Sale and use of both substances is illegal in Pakistan and is not considered a threat for road traffic injuries . However literature hints that this may not be the case . We did this study to assess usage of alcohol and marijuana in Pakistani commercial drivers . Methods A sample of 857 commercial bus and truck drivers was interviewed in October 2008 at the largest commercial vehicle station in Rawalpindi and Islamabad , Pakistan .  Time location cluster sampling was used to select the subjects and a structured question naire was used to assess the basic demographic profile , substance abuse habits of the drivers while on the road , and reasons for usage of illicit substances while driving were recorded . Self reported information was collected after obtaining informed consent . Chi square and fisher exact tests were used to assess differences between groups and logistic regression was used to identify significant associations between driver characteristics and alcohol and marijuana use . Results Almost 10 % of truck drivers use alcohol while driving on Pakistani roads . Marijuana use is almost 30 % in some groups . Statistically different patterns of usage are seen between population subgroups based on age , ethnicity , education , and marital status . Regression analysis shows association of alcohol and marijuana use with road rage and error behaviours , and also with an increased risk of being involved in road crashes . The reported reasons for using alcohol or marijuana show a general lack of awareness of the hazardous nature of this practice among the commercial driver population . Conclusion Alcohol and marijuana use is highly prevalent in Pakistani commercial drivers . The issue needs to be recognized by concerned authorities and methods such as r and om breath tests and sobriety check points need to be employed for proper law enforcement The purpose of this article is to compare the differential rate of detection of illicit drugs when using two distinct sample types , hair and urine specimens . The specimens were collected from persons who applied for employment as a truck driver , or were collected from r and omly selected currently employed truck drivers . The data is examined for job applicants and employees to determine if any differences in outcomes are associated with employment status or specimen type . The data is also assessed for specific patterns associated with particular drugs and their assay outcomes . Overall , it was determined that drug positive cases are relatively rare . Job applicants are more likely to test positive for an illicit drug than a currently employed driver . Applicants are more frequently positive for a drug by a factor of 3 for both urinalysis and hair analysis when compared to currently employed drivers . Approximately 2 % of applicants were urine positive and 9 % hair positive for an illegal drug . Considering employed truck drivers 0.6 % were drug positive by urinalysis and 3 % when using hair analysis . It is concluded that hair assays detect more drug use than urinalysis . It is also concluded that when urine and hair assay outcomes are non-concordant the typical case is a positive hair analysis with a negative urinalysis OBJECTIVE This study examined the impact of r and om alcohol testing , implemented on August 1 , 1994 , on the likelihood that the driver of a large truck involved in a fatal motor vehicle crash was alcohol-involved . METHOD Among fatal crashes , the  proportion of alcohol-positive large truck drivers ( intervention group )  was compared with the proportion of alcohol-positive light passenger vehicle drivers ( control group ) . Annual Fatality Analysis Reporting System ( FARS ) data ( 1988 - 2003 ) were compiled for each of the 50 states and Washington , D.C. , for the control and intervention groups . Using these pooled cross-sectional data , logistic regression modeled the likelihood that a driver was alcohol-positive ( blood alcohol concentration > 0 ) before compared with after r and om alcohol testing . We attributed the difference-in-difference ( the difference in likelihoods of being alcohol positive pretesting versus post-testing in large truck versus passenger vehicle drivers ) to the impact of r and om testing . RESULTS Drivers of large trucks were 18.6 % less likely to be alcohol-involved after r and om testing was implemented than before r and om testing ( odds ratio [ OR ] = 0.814 , 95 % confidence interval [ CI ] : 0.713 - 0.930 ) . The control group of passenger car drivers was 4.7 % less likely to be alcohol-involved after r and om testing was implemented ( OR = 0.953 , 95 % CI : 0.924 - 0.983 ) . The net reduction in the odds of alcohol involvement for drivers of large trucks was 14.5 % ( OR = 0.855 , 95 % CI : 0.748 - 0.976 ) . CONCLUSIONS Controlling for the general declining trend in alcohol-involved drivers in fatal crashes , r and om alcohol testing was correlated with a 14.5 % reduction in alcohol involvement among large truck drivers The effects of 28 h of sleep deprivation were compared with varying doses of alcohol up to 0.1 % blood alcohol concentration ( BAC ) in the same subjects . The study was conducted in the laboratory . Twenty long-haul truck drivers and 19 people not employed as professional drivers acted as subjects . Tests were selected that were likely to be affected by fatigue , including simple reaction time , unstable tracking , dual task , Mackworth clock vigilance test , symbol digit coding , visual search , sequential spatial memory and logical reasoning . While performance effects were seen due to alcohol for all tests , sleep deprivation affected performance on most tests , but had no effect on performance on the visual search and logical reasoning tests . Some tests showed evidence of a circadian rhythm effect on performance , in particular , simple reaction time , dual task , Mackworth clock vigilance , and symbol digit coding , but only for response speed and not response accuracy . Drivers were slower but more accurate than controls on the symbol digit test , suggesting that they took a more conservative approach to performance of this test . This study demonstrated which tests are most sensitive to sleep deprivation and fatigue . The study therefore has established a set of tests that can be used in evaluations of fatigue and fatigue counter measures Blood or urine sample s or both were obtained from 317 of 359 r and omly selected tractor-trailer drivers asked to participate in a driver health survey conducted at a truck weighing station on Interstate 40 in Tennessee . Altogether , 29 % of the drivers had evidence of alcohol , marijuana , cocaine , prescription or nonprescription stimulants , or some combination of these , in either blood or urine . Cannabinoids were found in 15 % of the drivers ' blood or urine ; nonprescription stimulants such as phenylpropanolamine were found in 12 % ; prescription stimulants such as amphetamine were found in 5 % ; cocaine metabolites were found in 2 % ; and alcohol was found in less than 1 % . These results provide the first objective information about the use of potentially abusive drugs by tractor-trailer drivers . The extent of driver impairment attributable to the observed drugs is uncertain because of the complex relationship between performance and drug concentrations This pilot intervention study evaluated the effect of feedback actigraphy on sleep and sleep-related variables in a group of long-haul truck drivers .  Visual feedback from actigraphs provided cues to the truck drivers , alerting them to their accumulated sleep times . Exposure to the cues was hypothesized to lead truck drivers to modify their behavior and result in improvement in sleep and sleep-related variables . It was predicted that exposure to feedback actigraphy would be associated with more sleep ( quantity ) , better sleep ( quality ) , a more positive attitude toward sleep , less subjective sleepiness , and increased control over sleep behavior by the sample Two motives for alcohol consumption have been emphasized in the etiological and the reasons -for-drinking literature : ( a ) people drink alcohol to cope with stress , and ( b ) people drink alcohol because of social influences . There is support for both of these hypotheses , but the results are usually modest and most authors agree that more complex theories of alcohol consumption are needed . This study examined the interactional effects of reasons for drinking alcohol  and situational factors on alcohol consumption .  St and ardized telephone interviews were conducted with 781 r and omly selected Michigan drinkers . Hierarchical multiple regression analyses indicated that gender , friends ' alcohol consumption , coping , and social motives for drinking were significant predictors of study participants ' alcohol consumption . As predicted , there was a significant interaction between drinking to cope with stress and perceived stress , and there was also a significant interaction between drinking for social reasons and friends ' alcohol consumption . Similarities and differences in the results for women , men , Blacks , and Whites are described Drugs are important risk factors for traffic accidents . In Brazil , truck drivers report using amphetamines to maintain their extensive work schedule and stay awake . These drugs can be obtained without prescription easily on Brazilian roads . The use of these stimulants can result in health problems and can be associated with traffic accidents . There are Brazilian studies that show that drivers use drugs . However , these studies are question naire-based and do not always reflect real-life situations . The purpose of this study was to demonstrate the prevalence of drug use by truck drivers on the roads of Sao Paulo State , Brazil , during 2009 . Drivers of large trucks were r and omly stopped by police officers on the interstate roads during morning hours . After being informed of the goals of the study , the drivers gave written informed consent before providing a urine sample . In addition , a question naire concerning sociodemographic characteristics and health information was administered . Urine sample s were screened for amphetamines , cocaine , and cannabinoids by immunoassay and the confirmation was performed using gas chromatography-mass spectrometry ( GC-MS ) . Of the 488 drivers stopped , 456 ( 93.4 % ) provided urine sample s , and 9.3 % of them ( n=42 ) tested positive for drugs . Amphetamines 
    Output:
    
The frequency of psychoactive substance use by truck drivers seems to be high , although that greatly varies according to the type of substance and the method of collecting the information .
The use of these substances was mainly associated with indicators of poor working conditions