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991.
Confusion has resulted from using the term "reliability" tomean both measurement-error variance and sampling-error variance.This article discusses the conceptual similarities and differencesbetween the various types of variance subsumed under "reliability"in order to distinguish among them.  相似文献   
992.
Few studies have examined academic researchers' understandings or attitudes toward conflict of interest policies even though these understandings and attitudes represent a crucial component of both compliance and educational efforts. This study reports the results of a large-scale, cross-sectional survey of research faculty at the nine campuses of the University of California regarding their understandings of and attitudes toward campus conflict of interest policies. We gathered information on their general assessments of investigators with financial ties to industry sponsors and reactions to the process of implementing conflict of interest policies at their respective campuses. We surveyed 1,971 faculty members from the nine-campus University of California system and had 779 responses (39% response rate). The sampled faculty were in the ten departments with the most number of financial disclosures at each campus. We utilized the WebSurveyor software to create a secure, online, 21-item survey. Our study reveals faculty with complex, sometimes contradictory, feelings about academic-industry relationships and highlights perceived gaps in policy and process. Most respondents were concerned about unlimited financial relationships, but a sizable number also viewed campus policies as irrelevant. Some expressed considerable anger over the process of policy implementation, rejecting the policies on the basis of professional and individual self-determination and moral integrity. Our study suggests the need for renewed efforts to encourage awareness of the relevance of conflict of interest policies for all faculty, new efforts to increase understanding of the situational nature of conflicts of interest, and reexamination of the processes of policy implementation at the campus level.  相似文献   
993.
Twenty-four-hour recall data from the Continuing Survey of Food Intake by Individuals (CSFII) are frequently used to estimate dietary exposure for risk assessment. Food frequency questionnaires are traditional instruments of epidemiological research; however, their application in dietary exposure and risk assessment has been limited. This article presents a probabilistic method of bridging the National Health and Nutrition Examination Survey (NHANES) food frequency and the CSFII data to estimate longitudinal (usual) intake, using a case study of seafood mercury exposures for two population subgroups (females 16 to 49 years and children 1 to 5 years). Two hundred forty-nine CSFII food codes were mapped into 28 NHANES fish/shellfish categories. FDA and state/local seafood mercury data were used. A uniform distribution with minimum and maximum blood-diet ratios of 0.66 to 1.07 was assumed. A probabilistic assessment was conducted to estimate distributions of individual 30-day average daily fish/shellfish intakes, methyl mercury exposure, and blood levels. The upper percentile estimates of fish and shellfish intakes based on the 30-day daily averages were lower than those based on two- and three-day daily averages. These results support previous findings that distributions of "usual" intakes based on a small number of consumption days provide overestimates in the upper percentiles. About 10% of the females (16 to 49 years) and children (1 to 5 years) may be exposed to mercury levels above the EPA's RfD. The predicted 75th and 90th percentile blood mercury levels for the females in the 16-to-49-year group were similar to those reported by NHANES. The predicted 90th percentile blood mercury levels for children in the 1-to-5-year subgroup was similar to NHANES and the 75th percentile estimates were slightly above the NHANES.  相似文献   
994.
Discover how an Oregon medical clinic made great strides decreasing radiology utilization after implementing a continuous quality improvement project that was embraced by physicians.  相似文献   
995.
For a Boolean function given by a Boolean formula (or a binary circuit) S we discuss the problem of building a Boolean formula (binary circuit) of minimal size, which computes the function g equivalent to , or -equivalent to , i.e., . In this paper we prove that if P NP then this problem can not be approximated with a good approximation ratio by a polynomial time algorithm.  相似文献   
996.
Serious nonaccidental head trauma (NHT) can leave permanent neurological damage in children who survive abuse. This study reports on child welfare's handling of NHT cases compared with cases of physical abuse and head trauma due to neglect with regard to placement in foster care, reunification with family, and safety issues. The results show that workers placed children with NHT in foster care immediately after the abuse but treated them no differently than other physically abused children regarding reunification.  相似文献   
997.
In evaluating family preservation services, it is important not only to study the service outcomes and the family characteristics, but also what actually happens during the treatment. This requires a program model. This article describes how a program model works, prescribes how workers should carry it out, and describes how researchers should measure the program's characteristics. The authors use data from Families First in The Netherlands to test the model. Results show that the method of the program meets the specified characteristics. The results are important for treatment, policy, education, and evaluation research.  相似文献   
998.
Children in foster care have lower health status than do their peers and limited access to health care. The Illinois Department of Children and Family Services developed HealthWorks, a separate primary care preferred provider system for children in foster care. This study compared claims data for children in HealthWorks with children not enrolled in HealthWorks and with children in Aid to Families with Dependent Children (AFDC) who had never entered foster care. Children enrolled in HealthWorks were more likely than were other children to receive all of the services except general inpatient hospitalizations. They had greater odds of receiving general exams and physicians' services and were more likely to visit the emergency room than children who were not enrolled. They were more likely to receive all of the measured services when compared with children receiving Medicaid through AFDC.  相似文献   
999.
Psychiatric medication use for children has increased dramatically over the past three decades. Despite substantial media attention to the issue, little is known about how the lay public feels about the use of psychiatric medications for children. Drawing on theories of medicalization, we describe and analyze Americans' attitudes towards the use of psychiatric medications generally and Prozac specifically for children described as having three types of behavioral problems. Using data from the 1998 General Social Survey's Pressing Issues in Health and Medical Care Module, we find that more Americans (57%) are willing to use psychiatric medications for children who have expressed suicidal statements than for "oppositional" behaviors (34.2%) or for hyperactivity (29.5%). Across the board, respondents are less willing to give Prozac than the general class of psychiatric medications. While socio-demographics do little to identify Americans with differing positions, the strongest and most consistent correlates of willingness to give psychiatric medications to children are trust in personal physicians, general attitudes towards psychiatric medications, and the respondent's expressed willingness to take psychiatric medications herself or himself.  相似文献   
1000.
Men with and without sexual dysfunction present with varying patterns of agreement between subjective estimates of sexual arousal and more objective psychophysiological measures of the same construct. This relative accuracy seems to be associated with sexual function, with men who have sexual dysfunction presenting less accurate estimations (mostly reporting below measured arousal levels). The purpose of this study is to clarify the processes underlying sexual arousal and the accuracy of its self-estimation. We looked at potential predictors of sexual arousal (subjective and physiological) and accuracy in estimating objective sexual arousal in a sample of 60 sexually functional males. Predictors included pre-existing sexual attitudes (erotophobia), both trait and state positive and negative affect, self-focused attention, and interoceptive awareness. Results indicate that this sexually functional sample generally reported below their own erection level. Interestingly, trait negative affect was associated with somewhat lower levels of subjective arousal and higher levels of physiological arousal. On the other hand, state positive affect facilitated both subjective and objective arousal and increased somewhat the accuracy of estimates of erectile responding. Pre-existing sexual attitudes as well as variations in self-focused attention and interoceptive awareness evidenced little effect on sexual arousal or the accuracy of its estimation.  相似文献   
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