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Drug screening through urinalysis is a widely accepted tool for rapid detection of potential drug use at a relatively low cost. It is, therefore, a potentially useful method for detecting and monitoring drug use in a variety of contexts such as the criminal justice system, pre-employment screening and a variety of treatment centers. This article explores the efficacy of two commercially available drug-screening assays: Online KIMS assay (Roche) and EMIT II assays. First, we evaluate the sensitivity and specificity of two immunoassays. A total of 738 urine samples were collected among adult arrestee populations from Chicago, New Orleans and Seattle through the Arrestee Drug Abuse Monitoring (ADAM) program. Partial samples were split within one laboratory and analyzed by both enzymes multiplied immunoassay technique (EMIT) II and kinetic interaction of microparticle in solution (KIMS) assays for a 10-drug panel (amphetamine, barbiturates, benzodiazepines, marijuana, cocaine, methadone, methaqualone, opiate, phencyclidine and propoxyphene). Gas chromatography-mass spectrometry (GC-MS) was used as a confirmation method for all positives from either EMIT II or KIMS for all experiments. Second, the paper examines whether using different testing laboratories plays a role in the final results. The same experiments were repeated at two different testing locations: one in California and one in London and England. Third, the paper studies whether drug testing results vary between two laboratories when each of them had used their own routine screening method: the Forensic Science Service (FSS) at Birmingham, United Kingdom with KIMS assay and Medscreen Limited at London, United Kingdom with EMIT II. In summary, both EMIT II and KIMS assays generate fairly consistent results. The concordance rate against each of the 10 drugs tested is relatively high (97.4-100%). The discrepancies, in most cases, occurred at drug concentrations near the cut-off levels. There were more discrepant results between two laboratories compared to when specimens were analyzed at the same laboratory using two different assays.  相似文献   
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This study provides an empirical analysis of the effects of advertising and commercial practice on the price and quality of optometrists' services. Data were collected by actually purchasing eye examinations and eyeglasses from optometrists in cities with and without restrictions on advertising and commercial practice. Analysis of the data supports the view that advertising and commercial practice lower prices but do not lower the quality of professional care available in the market. The implications of these findings are discussed.  相似文献   
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Using data from a new household survey on environmental attitudes, behaviors, and policy preferences, we find that current weather conditions affect preferences for environmental regulation. Individuals who have recently experienced extreme weather (heat waves or droughts) are more likely to support laws to protect the environment. We find evidence that the channel through which weather conditions affect policy preference is via perceptions of the importance of the issue of global warming. Furthermore, environmentalists and individuals who consult more sources of news are less likely to have their attitudes toward global warming changed by current weather conditions. These findings suggest that communication and education emphasizing consequences of climate change salient to the individual's circumstances may be the most effective in changing attitudes of those least likely to support proenvironment policy. In addition, the timing of policy introduction could influence its success.  相似文献   
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There is debate as to whether secure hospital treatment for offenders with personality disorder can be effective relative to criminal justice interventions. This study examines the evidence for long-term treatment of such offenders in hospital within in a modified therapeutic community model including accredited offending behaviour programmes. A panel sample of 47 patients were followed up on measures of violence risk (HCR-20, VRS) and symptom severity (SCL90-R). Intention-to-treat analysis with reliability thresholds showed significant positive change between assessment and discharge in both violence risk (VRS) and symptoms (SCL90-R) indicating a positive treatment effect. Threshold effects for treatment effectiveness seemed to occur at 1?year of treatment for risk and 3?years for symptom reduction.  相似文献   
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