A review of the epidentiological research on child sexual abuse. Community and college student samples

This article is the first of two consecutive reviews on the major empirical studies which have been carried out in an attempt to estimate the prevalence of child sexual abuse among females. The research is structured in terms of three sample categories: (a) probability and non-probability samples of the general population; (b) college student samples; and (c) clinical inpatient and outpatient samples. This part of the review deals with (a) and (b) and highlights a number of unresolved methodological issues which may contribute to the variance in reported prevalence rates. These include a myriad of definitions of child sexual abuse and different methods of eliciting information on possible histories of abuse. Despite these problems. taken as a whole the prevalence studies indicate the significant numbers of people who have experienced abuse and who are willing to disclose aspects of these abusive experiences.     

A simple estimator for a shared frailty regression model

Summary. We propose a simple estimation procedure for a proportional hazards frailty regression model for clustered survival data in which the dependence is generated by a positive stable distribution. Inferences for the frailty parameter can be obtained by using output from Cox regression analyses. The computational burden is substantially less than that of the other approaches to estimation. The large sample behaviour of the estimator is studied and simulations show that the approximations are appropriate for use with realistic sample sizes. The methods are motivated by studies of familial associations in the natural history of diseases. Their practical utility is illustrated with sib pair data from Beaver Dam, Wisconsin.     

The epidemiology of schizophrenia among Caribbean-born and first- and second-generation migrants in Britain

The study of migrants in their new environments is often a useful means of investigating environmental influences on health. Migrants have been found to develop higher rates of mental illness compared to their counterparts who remain at home. These deleterious effects of migration have been attributed to selection factors and stressful life experiences. Migration from an agricultural and traditional society to an urban industrial society where value systems can be demanding, often leads to role strain and role conflict. These kinds of incongruities are the beginning of a series of stressful experiences that contribute to poor health/mental health status. The extent to which one experiences stress is dependent on a number of factors. First, it depends on the perceived difference between home and the new environment. Second, it depends on the cultural homogeneity of the new environment, that is, the extent to which the migrant is readily assimilated into the new culture or is able to maintain a traditional lifestyle by living in an ethnic enclave, and the psychological resources available to successfully access services in the new environment. This paper examines the rates, incidence, and prevalence of schizophrenia found in Caribbean-born immigrants to Britain, and first- and second-generation people of Caribbean background born in Britain. It is argued that Afro-Caribbean people in England are overrepresented in the diagnosis of schizophrenia. Factors that may contribute to this finding range from unemployment, social disadvantage status, social adversity, racism in the health and criminal justice systems, and misdiagnosis.This paper was completed when the author served as Distinguished Visiting Professor-William Patterson College, Wayne, New Jersey.     

Incorporating Time‐Dose‐Response into Legionella Outbreak Models

A novel method was used to incorporate in vivo host–pathogen dynamics into a new robust outbreak model for legionellosis. Dose‐response and time‐dose‐response (TDR) models were generated for Legionella longbeachae exposure to mice via the intratracheal route using a maximum likelihood estimation approach. The best‐fit TDR model was then incorporated into two L. pneumophila outbreak models: an outbreak that occurred at a spa in Japan, and one that occurred in a Melbourne aquarium. The best‐fit TDR from the murine dosing study was the beta‐Poisson with exponential‐reciprocal dependency model, which had a minimized deviance of 32.9. This model was tested against other incubation distributions in the Japan outbreak, and performed consistently well, with reported deviances ranging from 32 to 35. In the case of the Melbourne outbreak, the exponential model with exponential dependency was tested against non‐time‐dependent distributions to explore the performance of the time‐dependent model with the lowest number of parameters. This model reported low minimized deviances around 8 for the Weibull, gamma, and lognormal exposure distribution cases. This work shows that the incorporation of a time factor into outbreak distributions provides models with acceptable fits that can provide insight into the in vivo dynamics of the host‐pathogen system.     

Measuring the Prevalence of Sector-Specific Problem Gambling: A Study of Casino Patrons

This study is the first attempt to measure the prevalence of problem gambling attributable to a specific sector of the gambling industry. One thousand, one hundred and five casino patrons in 40 casinos in the UK were interviewed, face-to-face. Respondents were screened for problem gambling using a multiple response version of DSM-IV (DSM-IV-MR). The study found support for Eadington's (1988) hypothesis, that UK casinos could be largely sustained by regular players, among whom the prevalence of problem gambling is high. The study also found support for the hypothesis that, to the extent different gambling sectors are patronised by demographically different client groups, so the problem gamblers associated with them will reflect these client groups. The problem gamblers among the regular casino patrons were demographically distinct from the problem gamblers in the sample who showed a preference for other gambling forms. Other key findings support those found in other jurisdictions. Sector-specific prevalence studies may be the next step forward in epidemiological research on problem gambling. They have the major advantage of netting significantly more problem gamblers from much smaller samples than similar studies in the general population. They also have the potential to reveal the proportion of problem gamblers attributable to each sector, along with their demographic characteristics. Such information would result in more specific information being available for regulators seeking to minimise the social impact of problem gambling and those involved in the development of prevention and treatment strategies.     

Using Epidemiological Studies to Check the Consistency of the Cancer Risks Predicted by High-Dose Animal Experiments: A Methodological Review

Epidemiological studies have been cited in the literature as evidence both for and against the human cancer risks predicted by high-exposure rodent studies. However, there has been little overall consistency in the ways that these animal-to-human comparisons have been made. This review examines some examples of these types of comparisons and describes the methods and techniques used by different investigators. Eleven "key decision areas" that need to be addressed are identified and recommendations for consistent, logical, and statistically appropriate approaches that might be taken to standardize the process are provided. In general, it is suggested that investigators provide the most useful information when they use logical, transparent, and statistically valid comparisons to pursue limited and focused objectives, such as directly testing the validity of an existing regulatory guidance value. Other recommendations include selecting biologically plausible extrapolative models that fit the data and drawing conclusions that are consistent with the study results and objectives.     

Perspectives on Incorporating Human Neurobehavioral End Points in Risk Assessments

Three topics are addressed: (1) measurement issues (e.g., the reliability and validity of neurobehavioral test scores), (2) general principles of assessment, including test selection, and (3) interpretation of scores. Psychological tests generally perform as well as medical tests in terms of reliability and validity. Test manuals, assessment textbooks, and psychologists are useful resources to the risk assessor. The variety of different tests employed in neurobehavioral studies complicates interstudy comparisons. In addition, tests that ostensibly assess the same general domain of function might assess somewhat different abilities within that domain. Although a uniform battery for use in all studies seems desirable, the battery appropriate for a specific study depends on study goals, knowledge about the mechanism(s) of neurotoxicity, nature of the study population, and pattern of exposure. Exposure-related neurobehavioral deficits are generally indicators of "altered function" rather than of "clinical disease." Limiting concern to end points corresponding to clinical disease might not be appropriate. Many neurobehavioral diagnoses are phenomenological and a neurotoxicant might cause a unique pattern of deficits for which no label has been created. The concern that a small shift in the central tendency of a distribution of test scores has no significance for the individual should be reexamined in light of the prevention paradox, formulated on the basis of epidemiologic studies of chronic disease. Poor performance on a neurobehavioral test does not necessarily map clearly onto underlying behavioral or neural substrate. The absence of such linkages, given current knowledge about brain-behavior relationships, should not reduce confidence in neurobehavioral end points. Use of neurobehavioral test scores involves considerations that differ little from those that the risk assessor routinely addresses in using end points commonly used in research on other topics in environmental epidemiology.     

Regression Modelling of Disease Risk in Relation to Point Sources

We describe a class of models for the investigation of possible raised risk of disease around putative sources of environmental pollution. An adaptation of the point process method suggested by Diggle and Rowlingson is presented, allowing the use of routinely available aggregated data and incorporating the more general distance–risk model suggested by Elliott and co-workers. An application to data on cancers of the stomach around municipal solid waste incinerators is presented.     

灰霾天气对人体健康的危害

灰霾是颗粒物和气体污染物导致的可察觉到的能见度降低的污染天气现象。近年来,随着城市化进程的快速发展,城市大气污染加剧,灰霾天气也随之增多。介绍了灰霾天气的形成过程、化学成分及其危害,并从流行病学等角度出发,对灰霾天气对人体健康效应的研究成果进行了综述。     

BSE Risk Assessment as a Basis for Updating French Screening Policy

The current French bovine spongiform encephalopathy (BSE) surveillance system, based on rapid testing of all cattle over 24 months of age and on clinical diagnosis, detects all clinical cases and some preclinical cases of BSE. Several indicators point to a marked shrinkage of the French BSE epidemic in recent years, owing to risk reduction measures. Meat and bone meal, the only known vector of the BSE agent, was banned in feed for all farmed species in November 2000. Thus the surveillance system may be relaxed. The objective of this risk assessment study was to provide information for decisionmakers on the minimum age at which healthy and high-risk cattle now need to be screened with rapid tests. For this purpose, we used the back-calculation method to project the course of the BSE epidemic. We examined the predicted patterns of the number and age distribution of cases of BSE that would be detected by the different existing surveillance streams. Various theoretical sensitivities of rapid tests were explored. Assuming that feed-borne sources of infection no longer exist, and that BSE does not occur spontaneously, our models suggest that it would have been possible to raise the minimum age for rapid tests to 66 months in early 2006, whereas theoretical reasoning, based on the assumption that the total meat and bone meal ban was effective in November 2001, suggests that this age cutoff could only be raised to 48 months in early 2006. These results only apply to cattle born and bred in France. If the situation remains unchanged, the age cutoff could be raised incrementally each year.