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71.
Online voting platforms have been introduced in some locations as the solution to the many barriers to political participation that disabled people continue to face. Reading the experiences of disabled student voters on university campuses alongside broader trends in electoral reform taking place in jurisdictions across Canada allows us to attend to the dangerous ways in which conversations around access have been limited through virtual solutions that encourage the physical absence of disabled voters. This article situates these absences alongside other categories of exclusion – including groups who are formally disenfranchised – and recalls many unstated values that are active in shaping citizenship cultures. Probing online voting through a critical disability angle, we present a critique of techno-fixes that builds upon broader notions of accessibility and inclusion.  相似文献   
72.
Clinical trials of experimental treatments must be designed with primary endpoints that directly measure clinical benefit for patients. In many disease areas, the recognised gold standard primary endpoint can take many years to mature, leading to challenges in the conduct and quality of clinical studies. There is increasing interest in using shorter‐term surrogate endpoints as substitutes for costly long‐term clinical trial endpoints; such surrogates need to be selected according to biological plausibility, as well as the ability to reliably predict the unobserved treatment effect on the long‐term endpoint. A number of statistical methods to evaluate this prediction have been proposed; this paper uses a simulation study to explore one such method in the context of time‐to‐event surrogates for a time‐to‐event true endpoint. This two‐stage meta‐analytic copula method has been extensively studied for time‐to‐event surrogate endpoints with one event of interest, but thus far has not been explored for the assessment of surrogates which have multiple events of interest, such as those incorporating information directly from the true clinical endpoint. We assess the sensitivity of the method to various factors including strength of association between endpoints, the quantity of data available, and the effect of censoring. In particular, we consider scenarios where there exist very little data on which to assess surrogacy. Results show that the two‐stage meta‐analytic copula method performs well under certain circumstances and could be considered useful in practice, but demonstrates limitations that may prevent universal use.  相似文献   
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Approximately half of nonmarital births are to mothers in cohabiting relationships, and an additional 30% are to mothers in visiting relationships. I use data (N= 1,945) from the Fragile Families Study to investigate whether the determinants of marriage in the year following a child's birth are similar for cohabiting and visiting parents. The results show that mothers’ education is predictive of marriage for cohabiting parents, whereas mothers’ earnings are predictive of marriage for visiting parents. The findings imply that visiting mothers place a greater emphasis on economic independence and sufficient resources to establish an independent household before transitioning to marriage. No differences in the association of relationship quality or attitudes and marriage are found.  相似文献   
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Substance use prevention programs empowering individual adolescents to resist substance use through education and skills training are crucial to reducing substance use within this population. However, existing programs of this type are designed primarily for classroom use, and may not meet the needs of social workers intervening with adolescents outside classroom settings. A literature review identified six programs that have demonstrated statistically significant reductions in substance use when implemented outside the classroom. The current study describes these programs, identifies their common characteristics, and draws on additional prevention research to outline recommendations for practitioners seeking to apply the field’s most current knowledge base in community settings.  相似文献   
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Conclusions The data presented in this paper and the earlier one in this series suggest that the effects of special comprehensive programs for school age mothers are seen most clearly in delay of the first pregnancy subsequent to the programs, as originally indicated by Klerman and Jekel (1973). Rather than terminating childbearing after the second pregnancy, those young mothers who had one subsequent pregnancy usually went on to become pregnant again rather quickly.A question can be raised about the generalizability of the finding from this study which is based on a rather small, black, poverty-lever sample. Although Furstenberg's (1976) results support those of this report in a population with similar characteristics, additional studies of white and non-poverty populations receiving a variety of services are critically needed if the country is to understand the phenomenon of adolescent pregnancy and find effective ways of minimizing its consequences.This study was supported by Grant #MC-R-090357 from the Maternal and Child Health Service, Public Health Service, Dept. of Health, Education and Welfare.  相似文献   
77.
Because of their mouthing behaviors, children have a higher potential for exposure to available chemicals through the nondietary ingestion route; thus, frequency of hand-to-mouth activity is an important variable for exposure assessments. Such data are limited and difficult to collect. Few published studies report such information, and the studies that have been conducted used different data collection approaches (e.g., videography versus real-time observation), data analysis and reporting methods, ages of children, locations, and even definitions of "mouthing." For this article, hand-to-mouth frequency data were gathered from 9 available studies representing 429 subjects and more than 2,000 hours of behavior observation. A meta-analysis was conducted to study differences in hand-to-mouth frequency based on study, age group, gender, and location (indoor vs. outdoor), to fit variability and uncertainty distributions that can be used in probabilistic exposure assessments, and to identify any data gaps. Results of this analysis indicate that age and location are important for hand-to-mouth frequency, but study and gender are not. As age increases, both indoor and outdoor hand-to-mouth frequencies decrease. Hand-to-mouth behavior is significantly greater indoors than outdoors. For both indoor and outdoor hand-to-mouth frequencies, interpersonal, and intra-personal variability are approximately 60% and approximately 30%, respectively. The variance difference among different studies is much bigger than its mean, indicating that different studies with different methodologies have similar central values. Weibull distributions best fit the observed data for the different variables considered and are presented in this article by study, age group, and location. Average indoor hand-to-mouth behavior ranged from 6.7 to 28.0 contacts/hour, with the lowest value corresponding to the 6 to <11 year olds and the highest value corresponding to the 3 to <6 month olds. Average outdoor hand-to-mouth frequency ranged from 2.9 to 14.5 contacts/hour, with the lowest value corresponding to the 6 to <11 year olds and the highest value corresponding to the 6 to <12 month olds. The analysis highlights the need for additional hand-to-mouth data for the <3 months, 3 to <6 months, and 3 to <6 year age groups using standardized collection and analysis because of lack of data or high uncertainty in available data. This is the first publication to report Weibull distributions as the best fitting distribution for hand-to-mouth frequency; using the best fitting exposure factor distribution will help improve estimates of exposure. The analyses also represent a first comprehensive effort to fit hand-to-mouth frequency variability and uncertainty distributions by indoor/outdoor location and by age groups, using the new standard set of age groups recommended by the U.S. Environmental Protection Agency for assessing childhood exposures. Thus, the data presented in this article can be used to update the U.S. EPA's Child-Specific Exposure Factors Handbook and to improve estimates of nondietary ingestion in probabilistic exposure modeling.  相似文献   
78.
The negative effects of incarceration on child well-being are often linked to the economic insecurity of formerly incarcerated parents. Researchers caution, however, that the effects of parental incarceration may be small in the presence of multiple-partner fertility and other family complexity. Despite these claims, few studies have directly observed either economic insecurity or the full extent of family complexity. We study parent-child relationships with a unique data set that includes detailed information about economic insecurity and family complexity among parents just released from prison. We find that stable private housing, more than income, is associated with close and regular contact between parents and children. Formerly incarcerated parents see their children less regularly in contexts of multiple-partner fertility and in the absence of supportive family relationships. Significant housing and family effects are estimated even after we control for drug use and crime, which are themselves negatively related to parental contact. The findings point to the constraints of material insecurity and the complexity of family relationships on the contact between formerly incarcerated parents and their children.  相似文献   
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