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Surveillance of noise exposure in the Danish workplace: a baseline survey   总被引:2,自引:0,他引:2  
Aims: To evaluate an epidemiological approach to a national noise hazard surveillance strategy, and report current exposure levels in the Danish workplace.

Methods: A study base of 840 companies in 10 selected high risk industries in the largest county in Denmark was identified from a national register. Noise exposure was measured among manual workers recruited from a random sample of workplaces in each industry. For reference, financial companies and a sample of residents were investigated according to the same protocol. The A-weighted equivalent sound level (LAeq) for a full shift was measured by portable dosimeters worn by 830 workers employed at 91 workplaces (67% of 136 eligible companies).

Results: The epidemiological design proved feasible and established a baseline for future noise surveillance. Substantial resources were needed to motivate workplaces to enlist and the final participation rate was less than optimal (66.9%). The LAeq (8) values in the selected industries were highly elevated (mean 83.7 dB(A) (95% CI 83.3 to 84.1) in comparison with residents and office workers (mean 69.9 dB(A), 95% CI 68.8 to 71.0). Some 50% of the workers were exposed to more than 85 dB(A) and some 20% to more than 90 dB(A) in several industries.

Conclusion: Noise levels in Danish high risk industries remain high. A substantial proportion of workers are exposed to noise levels above the current threshold limit of 85 dB(A). Ongoing surveillance of noise exposure using full shift dosimetry of workers in random samples of workplaces most at risk to high noise levels may help reinforce preventive measures. Such a programme would benefit from compulsory workplace participation.

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OBJECTIVES: Clinical trials in humans in Germany-as in many other countries-must be approved by local research ethics committees (RECs). The current study has been designed to document and evaluate decisions of chairpersons of RECs in the problematic field of non-therapeutic research with minors. The authors' purpose was to examine whether non-therapeutic research was acceptable for chairpersons at all, and whether there was certainty on how to decide in research trials involving more than minimal risk. DESIGN: In a questionnaire, REC chairpersons had to evaluate five different scenarios with (in parts) non-therapeutic research. The scenarios described realistic potential research projects with minors, involving increasing levels of risk for the research participants. The chairpersons had to decide whether the respective projects should be approved. METHODS: A total of 49 German REC chairpersons were sent questionnaires; 29 questionnaires were returned. The main measurements were approval or rejection of research scenarios. RESULTS: Chairpersons of German RECs generally tend to accept non-therapeutic research with minors if the apparent risk for the participating children is low. If the risk is clearly higher than "minimal", the chairpersons' decisions differ widely. CONCLUSION: The fact that there seem to be different attitudes of chairpersons to non-therapeutic research with minors is problematic from an ethical point of view. It suggests a general uncertainty about the standards of protection for minor research participants in Germany. Therefore, further ethical and legal regulation of non-therapeutic research with minors in Germany seems necessary.  相似文献   
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BACKGROUND: The rising prevalence of obesity in children may be due to a reduction in physical activity (PA). OBJECTIVE: Our aim was to study the associations of objectively measured PA volume and its subcomponents with indicators of body fatness. DESIGN: A cross-sectional study of 1292 children aged 9-10 y from 4 distinct regions in Europe (Odense, Denmark; the island of Madeira, Portugal; Oslo; and Tartu, Estonia) was conducted. PA was measured by accelerometry, and indicators of body fatness were the sum of 5 skinfold thicknesses and body mass index (BMI; in kg/m(2)). We examined the associations between PA and body fatness by using general linear models adjusted for potential confounding variables. RESULTS: After adjustment for sex, study location, sexual maturity, birth weight, and parental BMI, time (min/d) spent at moderate and vigorous PA (P = 0.032) and time (min/d) spent at vigorous PA were significantly (P = 0.015) and independently associated with body fatness. Sex, study location, sexual maturity, birth weight, and parental BMI explained 29% (adjusted R(2) = 0.29) of the variation in body fatness. Time spent at vigorous PA explained an additional 0.5%. Children who accumulated <1 h of moderate PA/d were significantly fatter than were those who accumulated >2 h/d. CONCLUSIONS: The accumulated amount of time spent at moderate and vigorous PA is related to body fatness in children, but this relation is weak; the explained variance was <1%.  相似文献   
996.
OBJECTIVE: To calculate the incidence and analyse the indications and outcome after surgical revascularization within the first 30 days after randomization of 1572 patients with acute myocardial infarction (MI) associated with ST-segment elevation (STEMI). DESIGN: Data regarding the patients undergoing heart surgery within the first 30 days after randomization were collected. RESULTS: Three patients (0.2%) with acute STEMI and randomized to percutaneous coronary intervention (PCI) underwent emergent coronary artery bypass grafting (CABG). A total of 50 patients (3.2%), 30 in the PCI group and 20 in the fibrinolysis group were revascularized by surgery within the first 30 days after randomization. The most frequent indication for surgery in both groups was unstable angina pectoris, followed by left main stenosis. The incidence of postoperative complications was higher compared with the outcome after elective CABG. CONCLUSIONS: The incidence of emergency CABG in this study was low (0.2%) after treatment of acute MI with either PCI or fibrinolysis. The overall incidence within 30 days was 3.2%, however, the mortality is increased with a 30-day mortality of 10% in this high-risk patient group.  相似文献   
997.
Zahl PH  Andersen JM  Maehlen J 《JAMA》2004,292(21):2579-2580
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Aim: To investigate whether the effect of socioeconomic position on risk of myocardial infarction (MI) is mediated by differential exposure or differential susceptibility to psychosocial work environment.

Methods: Data were used from three prospective population studies conducted in Copenhagen. A total of 16 214 employees, 44% women, aged 20–75 years, with initial examination between 1974 and 1992 were followed until 1996 for incident (hospital admission or death) MI. Register based information on job categories was used. Psychosocial job exposures were measured indirectly by means of a job exposure matrix based on the Danish Work Environment Cohort Study 1990.

Results: During follow up, 731 subjects were diagnosed with an MI: 610 men and 121 women (35% fatal). The hazards by socioeconomic position showed a graded effect with a hazard ratio (HR) of 1.57 (95% CI 1.23 to 2.03) for unskilled workers compared to executive managers. Despite a strong and graded association in risk of MI related to decision authority and skill discretion, only skill discretion mediated the effect of socioeconomic position. The HR for unskilled workers was reduced to 1.47 (0.93 to 2.31) after adjustment for decision authority and other cardiovascular risk factors, and to 1.07 (0.72 to 1.60) after adjustment for skill discretion and cardiovascular risk factors. No sign of synergy was found.

Conclusions: Decision authority and skill discretion were strongly related to socioeconomic position; and the effect on risk of MI was partially mediated by skill discretion. Improvements in psychosocial work environment, especially possibilities for skill discretion, might contribute to reducing the incidence of MI and social inequality in MI.

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