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11.
Unweighted estimators using data collected in a sample survey can be badly biased, whereas weighted estimators are approximately unbiased for population parameters. We present four examples using data from the 1988 National Maternal and Infant Health Survey to demonstrate that weighted and unweighted estimators can be quite different, and to show the underlying causes of such differences.  相似文献   
12.
Quality of care is the responsibility of each and every attending physician. There are many definitions of quality, none of which encompasses the universe of medical practice. Care that is neither medically necessary nor appropriate can never be considered good, no matter who renders it or how good the outcome. It is upon these premises that utilization review firms focus.  相似文献   
13.
Summary The paper explores issues raised by research on patterns ofwelfare and mutual care among older Pakistani people and theirfamilies, with particular reference to their use, or lack ofuse of social care services. Qualitative interviews were conductedwith (self-defined) minority ethnic older people, professionalsin statutory services and in minority-led community-based groups.The organization of services is discussed, with special referenceto issues of power and control, the role of the voluntary (non-profit)and statutory sectors, the debate regarding the possible needfor specialist versus generic services, and the role of minority-ledinitiatives. Secondly, issues of service staffing are examined,and the dangers of marginalizing minority services and staffreviewed, especially with reference to divisions of labour inservice provision and staff's own perspectives. Thirdly, themethodological implications of the work are explores, includingissues of linguistic and cultural communication and workingwith relatively powerless social groups, whose views are sought.Examining the views of professional social care workers is alsoproblematized, with reference to their gate-keeping role. Itis argued that user perspectives are essential to the developmentof appropriate services for minority ethnic groups. In conclusion,the need to raise these issues in other work is discussed.  相似文献   
14.
Summary. Inflation-type weighted estimators for variance components can be badly biased. Modified weighted estimators suggested in the literature are also badly biased for certain sampling designs. We propose new estimators for variance components, some of which are approximately unbiased regardless of the sampling design. These estimators require knowledge of the joint inclusion probabilities of the observations. The small sample properties of the estimators are studied via simulation for the simple one-way random-effects model. An application is given by using data from the US Hispanic Health and Nutrition Examination Survey.  相似文献   
15.
Application of Monte Carlo simulation methods to quantitative risk assessment are becoming increasingly popular. With this methodology, investigators have become concerned about correlations among input variables which might affect the resulting distribution of risk. We show that the choice of input distributions in these simulations likely has a larger effect on the resultant risk distribution than does the inclusion or exclusion of correlations. Previous investigators have studied the effect of correlated input variables for the addition of variables with any underlying distribution and for the product of lognormally distributed variables. The effects in the main part of the distribution are small unless the correlation and variances are large. We extend this work by considering addition, multiplication and division of two variables with assumed normal, lognormal, uniform and triangular distributions. For all possible pairwise combinations, we find that the effects of correlated input variables are similar to those observed for lognormal distributions, and thus relatively small overall. The effect of using different distributions, however, can be large.  相似文献   
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17.
Abstract

Objective: Low back pain (LBP) is a very common symptom. It occurs in all age groups from children to the elderly population. Globally, years lived with disability caused by LBP increased by 54% between 1990 and 2015. Our objective was to investigate measures that associate with LBP in students. Participants: A structured, anonymous, self-report questionnaire was distributed in two study years, 2009 and 2015. Participants included 1,026 students, 57.7% of them female, with a mean age of 27.2 (SD?=?6.4). Methods: The questionnaire included validated questions on various subjects related to health status and health behaviors. Results: The associated factors of undergraduate students experiencing backaches are higher if they engage in smoking (AOR?=?2.15; p<.01), report study-based stress (AOR?=?2.39; p<.01), and show depressive symptoms (AOR?=?2.69; p<.000). Conclusions: Smoking, stress, and depression are strong measures associated with backache in undergraduate students, significantly more than BMI, physical activity, or sedentary behaviors.  相似文献   
18.
Aging in the male is accompanied by steroid hormonal decline, and men may develop symptoms associated with hypogonadism. Increased awareness of ‘andropause’ in recent years has led to greater demand for hormonal assessments, resulting in a rising burden for health economics. We conducted a cross-sectional study to define men at risk for hypogonadism, in whom further hormonal investigation should be performed.

We examined 664 blue-collar workers aged 40–60 years at their workplace and determined hormonal status and body mass index (BMI). Men with an abnormal urogenital status and those on medication that might affect endocrine status were excluded from the study. All participants completed the validated Aging Male Symptom (AMS) questionnaire and obtained scores for psychological symptoms, somatovegetative symptoms, and sexual symptoms.

Multiple logistic regression analyses revealed a significantly increased risk (represented by the odds ratio) of psychological symptoms for men with low levels of testosterone and/or bioavailable testosterone (BAT). Increased BMI as well as low testosterone levels and/or low BAT levels raised the risk of somatovegetative symptoms. Each decrease of BAT by 1?ng/ml caused an approximately 1.8-fold increase of the risk (odds ratio?=?1.832, p?=?0.005). Additional independent risk factors were increased age and low luteinizing hormone (LH) level. Men aged 55 years with BMI >?28?kg/m2 and with somatovegetative symptoms and moderate or severe psychological symptoms had a 7.2-fold increase in the risk of a BAT level <?1.5?ng/ml compared to men without these risk factors (p <?0.001). Sensitivity and specificity were 75% and 71%, respectively.

The AMS score combined with age and BMI provides an easy and convenient method to identify men with probable androgen deficiency who require hormonal assessment.  相似文献   
19.
We documented the extent of point-of-sale (POS) lottery promotions in Ontario, Canada and the relationship between lottery promotions and store and city characteristics. This is the first quantitative study of POS lottery promotions. A total of 366 stores—independent and chain convenience stores, gas stations and grocery stores—were visited across 20 cities in Ontario. Data collectors unobtrusively observed the type of lottery promotions in each store and completed a data collection checklist. A lottery promotion index was created and hierarchical linear modeling (HLM) was conducted to examine the relationship between extent of lottery promotions and independent variables such as neighbourhood socioeconomic status and city prevalence of lottery ticket purchasing. POS lottery promotions were widespread across Ontario, with the highest level of promotion found in independent convenience stores. In the multivariable HLM model, none of the remaining independent variables remained statistically significant, except for store type. Lottery promotions are extensive at the POS in Ontario. These findings can help initiate discussions around the appropriateness and possible future regulation of this form of advertising.  相似文献   
20.
Gambling and the Health of the Public: Adopting a Public Health Perspective   总被引:3,自引:1,他引:2  
During the last decade there has been an unprecedented expansion of legalized gambling throughout North America. Three primary forces appear to be motivating this growth: (1) the desire of governments to identify new sources of revenue without invoking new or higher taxes; (2) tourism entrepreneurs developing new destinations for entertainment and leisure; and (3) the rise of new technologies and forms of gambling (e.g., video lottery terminals, powerball mega-lotteries, and computer offshore gambling). Associated with this phenomenon, there has been an increase in the prevalence of problem and pathological gambling among the general adult population, as well as a sustained high level of gambling-related problems among youth. To date there has been little dialogue within the public health sector in particular, or among health care practitioners in general, about the potential health impact of gambling or gambling-related problems. This article encourages the adoption of a public health perspective towards gambling. More specifically, this discussion has four primary objectives:1. Create awareness among health professionals about gambling, its rapid expansion and its relationship with the health care system;2. Place gambling within a public health framework by examining it from several perspectives, including population health, human ecology and addictive behaviors;3. Outline the major public health issues about how gambling can affect individuals, families and communities;4. Propose an agenda for strengthening policy, prevention and treatment practices through greater public health involvement, using the framework of The Ottawa Charter for Health Promotion as a guide.By understanding gambling and its potential impacts on the public's health, policy makers and health practitioners can minimize gambling's negative impacts and appreciate its potential benefits.  相似文献   
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