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891.
Terence P. Thornberry Beth Bjerregaard William Miles 《Journal of Quantitative Criminology》1993,9(2):127-158
Subject attrition is a potentially serious threat to the validity of inferences drawn from panel studies of delinquency and drug use. Prior assessments of this issue produce somewhat conflicting results, with some finding that respondents who leave the panel have higher rates of delinquency and drug use than those who remain, while other studies report little or no differential attrition. Despite these findings, there has been virtually no examination of the extent to which respondent attrition can bias substantive findings in panel studies of delinquency and drug use. The present article addresses this issue by simulating higher levels of attrition in an ongoing panel study that has a low rate of attrition and little differential attrition. It finds that failure to include more elusive respondents (those who are more mobile) would bias estimates of prevalence and frequency of delinquency and drug use as well as results from basic regression analyses. Failure to include less cooperative respondents (those who require more contacts) produces similar, but somewhat smaller, differences. The methodological implications of the results are discussed. 相似文献
892.
P Brown 《Journal of health politics, policy and law》1984,9(2):291-313
The right to refuse treatment is the most controversial of the rights of mental patients, and usually polarizes the movement for mental health reform between providers of care and external activist reformers. A broad alliance supported earlier struggles for recognition of patients' rights, but most professionals oppose recognizing this most extreme right of treatment refusal. Professional opposition to treatment refusal is not based on a wide extent of actual refusal; rather it derives from a defense against challenges to professional and institutional autonomy, an opposition to legal interference, and a belief that the community as well as the patient must be protected. These three reasons for opposition are examined by reviewing studies of attitudes toward patients' rights, knowledge about patients' rights, and implementation of patients' rights. Finally, the implications of these studies for future directions in the movement for patients' rights are examined. 相似文献
893.
894.
The hospital industry has recently experienced substantial merger activity. This paper examines several actual and proposed hospital mergers to determine the extent of competition in the affected markets and the effect these mergers may have on competition. Our focus is on mergers between hospitals in the same market. We define the relevant product and geographic market for hospitals, then develop criteria for evaluating hospital mergers and analyze several merger cases using these criteria. We conclude that these mergers threaten the competition that exists in most of the markets discussed, and that the claimed efficiency justification for mergers is not convincing. 相似文献
895.
C A Nichols P D Guerry M A Sens 《The American journal of forensic medicine and pathology》1990,11(1):71-73
A small wound found on the ear of a homicide victim was inflicted by either a knife or a sharp fragment of ceramic. To test the potential usefulness of cytologic examination of wound edges for fragments of inert material from the assault weapon, the wound was rinsed and cytologic filters were prepared from the retained rinsing material. The particulate matter present on filters included microscopic fragments of crockery admixed with blood and other tissue components. This observation supported other physical evidence that the wound was caused by the sharp edge of a ceramic crock rather than by the knife. This case demonstrates the potential usefulness of cytologic examination of wound edges. 相似文献
896.
P K Petrik 《The American journal of forensic medicine and pathology》1989,10(2):146-148
A case of sudden death due to massive small intestinal infarction is reported. The cause of the intestinal infarction was occlusion of mesenteric vessels by massive fibrosis secondary to carcinoid tumor. Since no primary carcinoid tumor was found in the intestine or elsewhere, it is suggested that the carcinoid tumor had originated in the mesentery. 相似文献
897.
898.
P I Lisaev 《Sudebno-meditsinskaia ekspertiza》1989,32(3):29-32
Possibilities of using casts of wound canals after organ stretching and fixation for determination of type of instrument used in case of stab-cut lung injuries were studied. In 70% of cases it was possible to make a conclusion on type and some parameters of cutting surface of an instrument used. 相似文献
899.
Robert P. George 《Law and Philosophy》1989,8(2):245-261
The author completed this article while on leave as a Visiting Fellow of New College, Oxford, on a grant from the George A. and Eliza Howard Foundation of Brown University. He wishes to acknowledge his debts to these institutions as well as to Christopher Wolfe, Daniel Robinson, William C. Porth, John Finnis, and the anonymous referee, all of whom criticized earlier drafts and offered valuable suggestions. 相似文献
900.
Intoxilyzer 5000 and blood-alcohol results from drivers arrested for operating a motor vehicle while intoxicated and for related offenses were compared during a two-year period. Three hundred and ninety-five pairs of results were studied. The breath- and blood-alcohol specimens in this study were collected within 1 h of each other. The mean blood-alcohol concentration obtained was 0.180 g/dL, with a range from zero to 0.338 g/dL. By comparison, the mean Intoxilyzer 5000 result was 0.16 g/210 L with a range from zero to 0.32 g/210 L. Compared with the blood-alcohol result, Intoxilyzer 5000 results were lower by more than 0.01 g/210 L 67% of the time, within 0.01 g/210 L 31% of the time, and higher by more than 0.01 g/210 L 2% of the time. 相似文献