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Biomedical subjects

D L Weed

Publications and source records attributed to D L Weed.

54 records · Page 3Linked to original sources
PubMed1993

Training researchers in cancer prevention and control: a description and evaluation of NCI's Cancer Prevention Fellowship Program.

NCI's Cancer Prevention Fellowship Program recently initiated a continuing evaluation of the fellows' demographics, fellows' accomplishments in the program, fellow and preceptor expectations and satisfaction, program strengths and weaknesses, current employment for former fellows, and ex-fellows' perceptions of program training. Evaluation shows that the program attracts quality applicants (including minorities and females) nationwide from many disciplines. The program successfully educates about cancer prevention and provides a positive preceptor experience with publication opportunities. Areas for improvement are data access, stipend, office space, job assistance, and networking. Recommendations for other programs include committed enthusiastic staff; adequate budget, space, and support; a formal learning experience in public health fundamentals, research methods, and cancer prevention; individual mentored research within a productive scientific program; aggressive recruitment; competitive admissions policy; defined objectives for fellows; and ongoing formal program evaluation.

Attitude of Health Personnel↗
PubMed1991

The case-control design and the assessment of the efficacy of cancer screening.

Case-control studies have been used in recent years to evaluate the efficacy of cancer screening. However, relatively little work has been done to examine the methodology itself for this purpose. In this paper, it is demonstrated that because of self-selection bias the case-control study can yield a biased estimate of screening efficacy. Further, it is shown how this bias can be assessed using data from a randomized trial. Using data from the HIP breast cancer screening study, the magnitude of the self-selection bias is estimated and is seen to be substantial.

Breast Neoplasms↗
PubMed1991

Physician compliance: improving skills in preventive medicine practices.

Physicians may not comply with all of the preventive medicine recommendations issued by recognized medical consensus groups. Compliance with recommendations for mammography, Papanicolaou tests and smoking cessation counseling is particularly important because of the potential to save lives. Compliance failure rates are often underestimated, in part because of misconceptions about the nature of physician compliance. An understanding of the difficulty in accurately estimating compliance and an awareness of the factors that affect compliance are fundamental to improving the delivery of preventive services.

Attitude of Health Personnel↗
PubMed1991

The merger of bioethics and epidemiology.

The merger of bioethics and epidemiology reflects the established idea that values are important for epidemiologic practice. It also reflects the more recent realization that standards of conduct are a timely addition to the profession. The thesis of this paper goes somewhat further and asserts that this merger represents an essential cornerstone in the foundation of a philosophy of epidemiology. Historical reflection reveals existing ontological and epistemological components to this same foundation. The union of bioethics and epidemiology suggests an important philosophical problem: selecting a method for unifying ethical and scientific reasoning. Solutions are proposed including: dialectic and critical rationalism.

Bioethics↗
PubMed1990

Epigenesis theory: a mathematical model relating causal concepts of pathogenesis in individuals to disease patterns in populations.

A mathematical modeling approach called epigenesis theory is presented which relates three aspects of pathogenesis to the population distribution of disease. The three aspects of pathogenesis involve how two or more measured variables interact. They are 1) whether the measured variables are related to the same causal action, 2) whether there is only one pathogenic process leading to disease, and 3) whether the measured variables contribute to the same pathogenic process. Epigenesis theory defines the following multivariable relations between two disease causes: 1) "Complementary" causes contribute different causal actions to the sole pathogenic process leading to disease. They have multiplicative relations. 2) "Separate process" causes contribute different causal actions to different pathogenic processes. They have the relations of simple independent action which are slightly less than additive. 3) "Intermediate" causes contribute different causal actions to the same pathogenic process in the presence of additional pathogenic processes where at most one of them may also participate. They have relations somewhere between multiplicative and simple independent actions. 4) "Cooperative-competitive" causes share the same causal action and act within the same pathogenic process. Their relations can change from greater than multiplicative to less than simple independent action at increasing dichotomization points of the measured variables. Epigenesis theory unifies the sufficient-component causes model and the simple independent action model and exceeds either model in the range of observations it can explain. It is most useful given directly causal measured variables and specific disease outcomes, but it will assist in etiologic investigations of nonspecific outcomes in which new disease classifications are proposed. While it is less useful given surveillance-type variables such as age or sex or outcomes resulting from numerous pathogenic processes such as death, it gains utility as more causal variables are entered into an analysis and as more cut points of continuous complementary, independent, or intermediate variables are distinguished.

Adult↗
PubMed1987

The healthy worker effect in actively working communications workers.

The healthy worker effect is examined in a large population of actively working communications workers. The mortality experience of 338,306 white male workers at the American Telephone and Telegraph Company grouped by age, duration of service, and general cause categories is compared with the mortality experience of US white males in 1976. Observed were statistically significant and often substantial deficits in mortality among these active workers in almost all categories. For cancers and cardiovascular diseases, mortality ratios tended to decrease across age in the subgroups with longer service durations; these ratios consistently increased across duration of service in older ages. In subgroups with long service durations, the secondary selection of the healthy worker effect in this active worker population appears to increase with increasing age.

Adult↗
PubMed1985

An epidemiological application of Popper's method.

The strong logicodeductive method of science is applied in an investigation of the mortality of a large population of communications workers (338 306 white men) to explain the mortality deficits so often observed in occupational studies. A theory for the healthy worker effect is proposed, and its predictions are tested in comparisons of mortality curves fitted to Weibull functions using regression techniques. The theory, based on the effect of selection on prevalent chronic disease, successfully predicts that as age increases the mortality rates of an employed population soon after hire will diverge from those of a general population. This new finding was observed for mortality from all causes, all causes minus accidents, cardiovascular diseases, and cancers. The theory successfully predicts the rate of decrease of the healthy worker effect as duration of service increases and the relative magnitudes of the effect by cause. Having survived initial empirical testing, this explanation for the effects of selection on occupational mortality meets at least two criteria (only one being sufficient) for deciding whether an explanation is to be preferred: it has made more precise predictions, and it has made new predictions not previously suggested.

Adult↗
PubMed1983

Ethics and chemoprevention research.

A systematic approach to ethics and ethical analysis has been advocated here to provide an answer to an important moral issue in contemporary medical research. That issue involves the course of action to be taken when human volunteers are injured as a direct result of nontherapeutic medical research. It was argued that compensation for such injury is a moral duty of society. It would be interesting to extend this argument and its conclusions to concrete application in clinical trials of nontherapeutic agents; this task will be left for others.

Antineoplastic Agents↗
PubMedDate not supplied

Comparison of information processing technologies.

OBJECTIVE: To examine the type of information obtainable from scientific papers, using three different methods for the extraction, organization, and preparation of literature reviews. DESIGN: A set of three review papers was identified, and the ideas represented by the authors of those papers were extracted. The 161 articles referenced in those three reviews were then analyzed using 1) a formalized data extraction approach, which uses a protocol-driven manual process to extract the variables, values, and statistical significance of the stated relationships; and 2) a computerized approach known as "Idea Analysis," which uses the abstracts of the original articles and processes them through a computer software program that reads the abstracts and organizes the ideas presented by the authors. The results were then compared. The literature focused on the human papillomavirus and its relationship to cervical cancer. RESULTS: Idea Analysis was able to identify 68.9 percent of the ideas considered by the authors of the three review papers to be of importance in describing the association between human papillomavirus and cervical cancer. The formalized data extraction identified 27 percent of the authors' ideas. The combination of the two approaches identified 74.3 percent of the ideas considered important in the relationship between human papillomavirus and cervical cancer, as reported by the authors of the three review articles. CONCLUSION: This research demonstrated that both a technically derived and a computer derived collection, categorization, and summarization of original articles and abstracts could provide a reliable, valid, and reproducible source of ideas duplicating, to a major degree, the ideas presented by subject specialists in review articles. As such, these tools may be useful to experts preparing literature reviews by eliminating many of the clerical-mechanical features associated with present-day scientific text processing.

Bibliometrics↗