ABSTRACT
The objective of this study was to determine whether breath alcohol elimination rate varies as a function of age, gender, and drinking practice, factorially combined. Eighty-four men and 84 women drank enough alcohol to produce peak BrACs of .110 g/210 L for heavy and moderate drinkers and BrACs of .090 g/210 L for light drinkers. An Intoxilyzer 5000 was used to generate the concentration-time profiles. Mean (M) elimination rates (g/210 L/h) were found to be higher for women (N=84, M=.0182, SD=.0033) than for men (N=84, M=.0149, SD=.0029), F(1, 144)=57.292, p<.001; higher for heavy drinkers (N=56, M=.0176, SD=.0038) than for light and moderate drinkers combined (N=112, M=.0160, SD=.0032), F(1, 144)=12.434, p<.01; and higher for older subjects (51-69 years, N=42, M=.0180, SD=.0038) than younger subjects (19-50 years, N=126, M=.0161, SD=.0033), F(1, 144)=14.324, p<.001. None of the two-way interactions (age × gender, age × drinking practice, gender × drinking practice) or the three-way interaction (age × gender × drinking practice) was statistically significant. Limitations of the current study and suggestions for further research are discussed.
Subject(s)
Breath Tests , Central Nervous System Depressants/pharmacokinetics , Ethanol/pharmacokinetics , Adult , Age Factors , Aged , Alcohol Drinking , Analysis of Variance , Female , Humans , Male , Middle Aged , Regression Analysis , Sex Factors , Young AdultABSTRACT
PROBLEM: The role of alcohol as a major factor in traffic crash causation has been firmly established. However, controversy remains as to the precise shape of the relative risk function and the BAC at which crash risk begins to increase. METHODS: This study used a case-control design in two locations: Long Beach, California, and Fort Lauderdale, Florida. Data were collected on 2,871 crashes of all severities and a matched control group of drivers selected from the same time, location, and direction of travel as the crash drivers. Of the 14,985 sample drivers, 81.3% of the crash drivers and 97.9% of the controls provided a valid BAC specimen. RESULTS: When adjusted for covariates and nonparticipation bias, increases in relative risk were observed at BACs of .04-.05, and the elevations in risk became very pronounced when BACs exceeded .10. DISCUSSION: The results provide strong support for .08 per se laws and for state policies that increase sanctions for BACs in excess of .15. IMPACT ON INDUSTRY: This study provides further precision on the deleterious effects of alcohol on driving and, by implication, on other complex tasks.
Subject(s)
Accidents, Traffic/prevention & control , Alcoholic Intoxication/diagnosis , Automobile Driving , Ethanol/blood , Accidents, Traffic/legislation & jurisprudence , Accidents, Traffic/statistics & numerical data , Alcoholic Intoxication/blood , Breath Tests , California/epidemiology , Case-Control Studies , Florida/epidemiology , Humans , RiskABSTRACT
This paper focuses on analyzing and improving patient flow at an outpatient clinic of the Indiana University Medical Group. A structured process analysis and improvement approach was used to identify sources of variability and improvement factors. A process map, that matched the flow process at the clinic, was developed and validated. Key sources of variability that had potential to contribute to congestion in flow were identified. Data on task times were collected by observing the process with stopwatch or from historical records. A simulation model corresponding to the process map was developed, and the output was validated. Several ideas to modify clinic operations were tested on the validated simulation model. The overall result was an improvement in both the mean and the standard deviation of patient wait time, as well as higher utilization of physicians' time. The clinic has implemented several of our recommendations and experienced significant improvements.
Subject(s)
Ambulatory Care Facilities/organization & administration , Computer Simulation , Efficiency, Organizational , Humans , Models, Organizational , Operations Research , Process Assessment, Health Care , Time and Motion Studies , Waiting Lists , WorkloadABSTRACT
OBJECTIVE: Development of a rational and enforceable basis for controlling the impact of cannabis use on traffic safety. METHODS: An international working group of experts on issues related to drug use and traffic safety evaluated evidence from experimental and epidemiological research and discussed potential approaches to developing per se limits for cannabis. RESULTS: In analogy to alcohol, finite (non-zero) per se limits for delta-9-tetrahydrocannabinol (THC) in blood appear to be the most effective approach to separating drivers who are impaired by cannabis use from those who are no longer under the influence. Limited epidemiological studies indicate that serum concentrations of THC below 10 ng/ml are not associated with an elevated accident risk. A comparison of meta-analyses of experimental studies on the impairment of driving-relevant skills by alcohol or cannabis suggests that a THC concentration in the serum of 7-10 ng/ml is correlated with an impairment comparable to that caused by a blood alcohol concentration (BAC) of 0.05%. Thus, a suitable numerical limit for THC in serum may fall in that range. CONCLUSIONS: This analysis offers an empirical basis for a per se limit for THC that allows identification of drivers impaired by cannabis. The limited epidemiological data render this limit preliminary.
