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1.
In this work, some corporate websites of the chemical industry of Tarragona (Spain) are studied, analysing how the chemical trade associations and companies present information and/or encourage dialogue with the community on issues relating to the chemical risk and their environmental, health and safety (EHS) performance. The results suggest that the chemical industry in Tarragona uses the corporate websites mainly to disseminate information about its EHS commitments and performance, but they do not encourage dialogue with the community through the Internet.  相似文献   
2.
Summary Meta-analyses of sets of clinical trials often combine risk differences from several 2×2 tables according to a random-effects model. The DerSimonian-Laird random-effects procedure, widely used for estimating the populaton mean risk difference, weights the risk difference from each primary study inversely proportional to an estimate of its variance (the sum of the between-study variance and the conditional within-study variance). Because those weights are not independent of the risk differences, however, the procedure sometimes exhibits bias and unnatural behavior. The present paper proposes a modified weighting scheme that uses the unconditional within-study variance to avoid this source of bias. The modified procedure has variance closer to that available from weighting by ideal weights when such weights are known. We studied the modified procedure in extensive simulation experiments using situations whose parameters resemble those of actual studies in medical research. For comparison we also included two unbiased procedures, the unweighted mean and a sample-size-weighted mean; their relative variability depends on the extent of heterogeneity among the primary studies. An example illustrates the application of the procedures to actual data and the differences among the results. This research was supported by Grant HS 05936 from the Agency for Health Care Policy and Research to Harvard University.  相似文献   
3.
Children in the child welfare system are dependent upon Medicaid to finance services for their considerable mental health needs. This study examines the effects of Medicaid policies on mental health service use among a national probability sample of children in the child welfare system. Data for this study came from the National Survey of Child and Adolescent Well-Being, the Caring for Children in Child Welfare study, and the Area Resource File. Weighted multivariate logistic regression analyses were conducted to estimate effects of policy variables on children's use of mental health services, controlling for child-level covariates and county-level health resources. Children in counties with behavioral carve-outs under Medicaid managed care had lower odds of inpatient mental health service use. Medicaid managed care enrollment and variations in type of provider reimbursement did not affect use of mental health services. Older age, greater need for mental health services, and higher levels of caregiver education were associated with increased odds of service use. Restrictions on use of inpatient mental healthcare caused by behavioral carve-outs may disproportionately affect children in the child welfare system who have high rates of such use. Careful adoption of carve-outs is necessary to assure appropriate care for these children.  相似文献   
4.
Research has repeatedly demonstrated that parent and child reports of child behavior and emotional functioning often do not agree in terms of symptom severity or even symptom presence. Given the potential clinical impact that discrepant reports may have on the therapeutic process, a significant amount of research has addressed the factors influencing this observed discrepancy. Traditionally, this research has evaluated the impact of demographic factors on mean differences and obtained correlation coefficients between parent and child reports. The current research improves upon previous research in this area in two ways. First, the current research uses parent and child measures with identical rather than similar items as is commonly found in previous research. Second, the current research moves beyond identifying demographic influences on discrepant reports by explaining observed discrepancies in terms of differences in parent and child perceptions of typical child behavior.David Carlston and Benjamin Ogles are affiliated with Department of Psychology, Ohio University, Athens, USA.Funding for this project was provided by the Ohio Department of Mental Health.  相似文献   
5.
Summary.  When evaluating potential interventions for cancer prevention, it is necessary to compare benefits and harms. With new study designs, new statistical approaches may be needed to facilitate this comparison. A case in point arose in a proposed genetic substudy of a randomized trial of tamoxifen versus placebo in asymptomatic women who were at high risk for breast cancer. Although the randomized trial showed that tamoxifen substantially reduced the risk of breast cancer, the harms from tamoxifen were serious and some were life threaten-ing. In hopes of finding a subset of women with inherited risk genes who derive greater bene-fits from tamoxifen, we proposed a nested case–control study to test some trial subjects for various genes and new statistical methods to extrapolate benefits and harms to the general population. An important design question is whether or not the study should target common low penetrance genes. Our calculations show that useful results are only likely with rare high penetrance genes.  相似文献   
6.
Mats Ekl  f 《Work and stress》2002,16(1):58-69
The frequency of occupational accidents in fishery is high in most fishery nations. Implementation of safety measures has, however, been limited. The purpose of the present cross-sectional study was to explore Swedish fishermen's attitudes towards occupational risks and accident control. Information was acquired through a questionnaire distributed to a convenience sample of 92 fishermen. Indices were built, containing variables relevant to perceived risk levels in connection with work, perceived manageability of risks, activity in safety work, technical knowledge and individual attitudes towards risks. The results did not support earlier findings of low risk awareness and risk acceptance among fishermen. Perceived manageability of risks but not perceived risk level, accident experience or risk acceptance, were significantly associated with activity in safety work. The results suggest that safety work might benefit from efforts to develop fishermen's understanding of how the development of hazardous situations can be prevented or managed. The results do not support strategies for accident control in fishery based solely on increasing risk awareness.  相似文献   
7.
Summary. The cumulative number of human immunodeficiency virus (HIV) infections worldwide has reached 60 million in little over 30 years. HIV continues to spread despite a detailed understanding of the manner in which it spreads and measures which can prevent spread. Some governments have been highly successful in containing the spread of HIV through blood products and from mother to child and among injecting drug users. Lack of political will, lack of resources or challenges to widely accepted scientific evidence have held back similar interventions in other countries. It has proved much more difficult to reduce the sexual transmission of HIV in both high and low income countries. A wide range of strategies has been identified but it remains unclear which strategies deserve priority and what methods of promoting them have the greatest effect. There is ample evidence that awareness of HIV and changes in sexual behaviour have occurred widely but the penetration of information remains poor in some vulnerable groups especially adolescents and women in poorer countries. Further obstacles face those who have information about the risk. The subordinate position of women and a desire for large families are important obstacles to condom negotiation and use. Urbanization, poverty, conflict and declining public services all exacerbate unsafe sexual behaviour. We argue that so-called 'structural' interventions directed at these wider contexts of unsafe behaviour merit greater attention. Such approaches have the added benefit of being less susceptible to 'risk compensation' which has the potential to undermine strategies directed at reducing the transmission efficiency of HIV.  相似文献   
8.
This article reports the results of a study that examined the ways in which current and recent TANF recipients assembled or “packaged” their child care arrangements among formal and informal providers. The findings are drawn from in-person, in-depth interviews with current and former welfare recipients. The study found that most of the respondents used multiple providers within the category of informal child care for reasons including availability, the use of a network of social acquaintances as a problem-solving resource, the need to accommodate irregular work hours, and personal trauma that contributed to a distrust of strangers in formal settings. The findings can affect the efficacy of practice with TANF recipients by contributing to social workers’ understanding of the context of decision-making regarding child care.  相似文献   
9.
Modeling for Risk Assessment of Neurotoxic Effects   总被引:2,自引:0,他引:2  
The regulation of noncancer toxicants, including neurotoxicants, has usually been based upon a reference dose (allowable daily intake). A reference dose is obtained by dividing a no-observed-effect level by uncertainty (safety) factors to account for intraspecies and interspecies sensitivities to a chemical. It is assumed that the risk at the reference dose is negligible, but no attempt generally is made to estimate the risk at the reference dose. A procedure is outlined that provides estimates of risk as a function of dose. The first step is to establish a mathematical relationship between a biological effect and the dose of a chemical. Knowledge of biological mechanisms and/or pharmacokinetics can assist in the choice of plausible mathematical models. The mathematical model provides estimates of average responses as a function of dose. Secondly, estimates of risk require selection of a distribution of individual responses about the average response given by the mathematical model. In the case of a normal or lognormal distribution, only an estimate of the standard deviation is needed. The third step is to define an adverse level for a response so that the probability (risk) of exceeding that level can be estimated as a function of dose. Because a firm response level often cannot be established at which adverse biological effects occur, it may be necessary to at least establish an abnormal response level that only a small proportion of individuals would exceed in an unexposed group. That is, if a normal range of responses can be established, then the probability (risk) of abnormal responses can be estimated. In order to illustrate this process, measures of the neurotransmitter serotonin and its metabolite 5-hydroxyindoleacetic acid in specific areas of the brain of rats and monkeys are analyzed after exposure to the neurotoxicant methylene-dioxymethamphetamine. These risk estimates are compared with risk estimates from the quantal approach in which animals are classified as either abnormal or not depending upon abnormal serotonin levels.  相似文献   
10.
This article argues that those interested in social policy should by definition be interested in issues of transport policy. It analyses data on road traffic fatalities and suggests, in the light of this evidence, that those who benefit least from the motor vehicle seem disproportionately likely, given their relative exposure to the risk, to die in road traffic accidents.  相似文献   
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