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641.
Fetal Alcohol Syndrome (FAS) is currently the major cause of mental retardation in the Western world. Since FAS is not a natural phenomenon and is created by mixing alcohol and pregnancy, the solution to decreasing the incidence of all alcohol-related birth defects is therefore entirely preventable. To date, little is known about the effectiveness of prevention programs in reducing the incidence of FAS. Therefore, it is the intention of this article to review the effectiveness of prevention programs in lowering the incidence of FAS. The present review revealed that prevention programs, to date, have been successful in raising awareness of FAS levels across the groups examined. However, this awareness has not been translated into behavioral changes in "high risk" drinkers as consumption levels in this group have decreased only marginally, indicating prevention programs have had minimal or no impact in lowering the incidence of FAS. Urgent steps must now be taken to fully test prevention programs, and find new strategies involving both sexes, to reduce and ultimately eliminate the incidence of FAS. 相似文献
642.
The authors use longitudinal data from the National Longitudinal Survey of Youth to investigate whether the wage trajectories of male high school dropouts are affected by the acquisition of the General Educational Development (GED) credential, by postsecondary education, and by training. The authors show that acquisition of the GED results in wage increases for dropouts who left school with weak skills, but not for dropouts who left high school with stronger skills. College and training provided by employers are associated with higher wages for male dropouts. 相似文献
643.
"This article is part of a larger study of public attitudes toward immigration in seven countries that historically and currently have had different policies and practices vis-a-vis immigration. The countries involved are Australia, Canada, France, Germany, Great Britain, Japan and the United States. The time frame for which most of the public opinion data will be reported is from 1970 through 1995. The data have been collected from national surveys that were conducted in each of the countries." 相似文献
644.
This article proposes and evaluates a method to test for mediation in multilevel data sets formed when an intervention administered to intact groups is designed to produce change in individual mediator and outcome variables. Simulated data of this form were used to compare ordinary least squares (OLS) and two multilevel estimators of the mediated effect. OLS and multilevel standard error approximations were also evaluated and recommendations given for optimal estimator choice. These methods were applied to data from an existing substance use intervention to show the impact multilevel mediation modeling can have on the conclusions drawn from real-world evaluation studies. 相似文献
645.
A system that includes a number of terrorist cells is considered. The cells can consist of one or more terrorists. The current number of terrorist cells is further denoted by N(t), where t is a current time counted from any appropriate origin. The objective is to find the evolution of the system in terms of N(t) and some interpretable parameters, such as the initial number of the terrorist cells N0=N(0), the cell disabling rate constant lambda (or the cell half-life t1/2), and the rate of formation of new cells P. The cost-effectiveness analysis, performed in the framework of the model, reveals that the effectiveness of disabling a terrorist cell is getting worse after 2-3 half-lives of a cell, which shows that if the anti-terrorist actions have not reached their goal during that time, the respective policy should be considered for revision, using the risk assessment consideration. Another important issue raised concerns balancing the efforts related to counterterrorism actions inside the system and the efforts protecting its borders. The respective data analysis is suggested and illustrated using simulated data. 相似文献
646.
Statistical Papers - In event history data, events often are not dated exactly but only a time interval is recorded. In contrast, common estimators for transition rate models assume exactly dated... 相似文献
647.
P.J. Danaher 《Australian & New Zealand Journal of Statistics》1988,30(3):263-275
A three-parameter generalisation of the beta-binomial distribution (BBD) derived by Chandon (1976) is examined. We obtain the maximum likelihood estimates of the parameters and give the elements of the information matrix. To exhibit the applicability of the generalised distribution we show how it gives an improved fit over the BBD for magazine exposure and consumer purchasing data. Finally we derive an empirical Bayes estimate of a binomial proportion based on the generalised beta distribution used in this study. 相似文献
648.
649.
Marianne Berry Ph.D. Richard P. Barth Ph.D. ACSW Barbara Needell M.S.W. 《Child and Adolescent Social Work Journal》1996,13(2):157-183
Information gathered from over 1000 adoptions in the fourth year of a prospective study of adoptions finds satisfaction levels to be quite high, with those families adopting through private agencies to feel best prepared and satisfied. Differences by adoption auspice are detailed and discussed.The senior authors are Co-Principal Investigators of the California Long-range Adoption Study. This research was supported by the Child Welfare Research Center, Family Welfare Research Group, University of California at Berkeley, through a grant from the Children's Bureau, Administration for Children and Families, Department of Health and Human Services. The authors wish to thank the families for their participation. Please address correspondence to Mary Berry at the Center for Child Welfare, UTA School of Social Work, P.O. Box 19129, Arlington, Texas 76019. 相似文献
650.
J. E. Berg S. Andersen J. I. Brevik P. Ø. Alveberg 《International Journal of Social Welfare》1996,5(1):30-34
Drug addict rehabilitation programs receive a small proportion of the funds made available through the social welfare system. Emphasis has traditionally been placed on the pathological rather than the salutogenic elements of an addicted lifestyle. A new test of a person's sense of coherence in life (Antonovsky's 9-item Sense of Coherence scale) may be of interest in rehabilitation work with drug addicts, and in focusing more attention on this aspect of addiction treatment. Thirty drug addicts in treatment and rehabilitation and 10 former drug addicts were interviewed using the 9-item Sense of Coherence scale. The results obtained were compared to a well known test of distress, the 24-item Symptom Checklist. Drug addicts in treatment facilities had significantly lower mean scores on the 9-item Sense of Coherence scale (2.3) and higher scores on the 24-item Symptom Checklist (2.3) than both drug addicts in rehabilitatively oriented institutions (3.3 and 1.6) and the long-term rehabilitated non-using former drug addicts (4.2 and 1.5 respectively). The differences between the group in rehabilitation and the former drug addicts were also statistically significant. The levels of the two psychometric tests suggested a gradual movement towards normal values and an increased sense of meaning in life among the former drug addicts, contrary to findings by other researchers. The length of time before these tests return to normal values may exceed the observation period often used in follow-up at treatment facilities. Increased social welfare may follow if a disclosure of salutogenic possibilities in drug addicts is obtained. Further prospective research is, however, necessary to confirm our findings. 相似文献