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201.
Researchers conducting longitudinal studies with children or adults are inevitably confronted with problems of attrition and missing data. Missing data in longitudinal studies is frequently handled by excluding from analyses those cases for whom data are incomplete. This approach to missing data is not optimal. On the one hand, if data are missing at random, then dropping incomplete cases ignores information collected on those cases that could be used to improve estimates of population parameters (e.g., means, variances, covariances, and growth rates) and improve the power of significance tests of statistical hypotheses. On the other hand, if data are not missing at random, then dropping incomplete cases leads to biased parameter estimates and hypothesis tests that may be internally and externally invalid. This study uses three years of follow-up data from a longitudinal investigation of neuropsychological outcomes of cancer in children to demonstrate the problems presented by missing data in repeated measures designs and some solutions. In evaluating potential biasing effects of attrition, the study extends previous research on neuropsychological outcomes in pediatric cancer by inclusion of patients whose disease had relapsed, and by comparison of surviving and nonsurviving patients. Although the data presented have specific relevance to the study of neuropsychological outcome in pediatric cancer, the problems of missing data and the solutions presented are relevant to a wide variety of diseases and conditions of interest to researchers in child and adult neuropsychology.  相似文献   
202.
Familial clustering of a disease is defined as the occurrence of the disease within some families in excess of what would be expected from the occurrence in the population. It has been demonstrated for several cancer types, ranging from rare cancers as the adenomatosis-coli-associated colon cancer or the Li-Fraumeni syndrome to more common cancers as breast cancer and colon cancer. Familial clustering, however, is merely an epidemiological pattern, and it does not tell whether genetic or environmental causes or both in combination are responsible for the familial clustering. Familial clustering may be due to genetic predisposition to the disease, but exposure to environmental factors — shared by members of some families, but not by members of other families — may also cause familial clustering and hence mimic genetic inheritance in the study of nuclear families. Based on assumptions regarding the individual steps in the biological process starting with exposure to carcinogens and ending with death from disseminated cancer we suggest that genetic and environmental factors may both be involved in most of these steps. The present paper focuses on research methodologies necessary to discriminate between the effect of genes and family environment in the development of cancer.  相似文献   
203.
This study reports the results of one effort to help supermarket shoppers alter food purchases to make purchases (and meals) that are lower in fat and higher in fiber. A prototype interactive information system using instructional video programs, feedback on purchases with specific goals for change, weekly programs, and the ability to track user interactions and intended purchases was evaluated. The major dependent measure was users' actual food purchases as derived from participants' highly detailed supermarket receipts. After a 5- to 7-week baseline phase, participants were randomly assigned to an experimental or control condition for the 7- to 8-week intervention phase. A follow-up phase began 5 to 8 weeks after participants completed the intervention and discontinued use of the system. The results indicated that experimental participants, when compared to control participants, decreased high fat purchases and increased high fiber purchases during intervention, with evidence for some maintenance of effect in follow-up. Plans for increasing the use and impact of the system are discussed.  相似文献   
204.
The present study aimed to describe how a volunteer peer support service assists women with breast cancer, and provides guidelines for practitioners in the development and implementation of such programmes. A two‐phase evaluation of a breast cancer peer support program was undertaken to describe important attributes of the peer support intervention, the impact of the volunteer visit on women's self‐reports of anxiety, and key indicators of a successful volunteer visit. Phase 1 included focus groups with 57 women previously treated for breast cancer. Phase 2 included a survey of 245 women also treated previously for breast cancer and visited by a Breast Cancer Support Volunteer. The key aspect of the peer support process was the bond of common experience leading to a decrease in social isolation, an increase in optimism about the future and reassurance about personal reactions and femininity. It is recommended that peer support programmes should aim to time support visits to coincide with the time when patient support needs are highest, that volunteers need to be recruited from a range of backgrounds and matched to patients most similar to them in way of life, and that peer support services should be embedded in a broad network of community support services. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
205.
Background/Objective:The aim was to analyse the psychometric properties of the 10-item version of the Connor-Davidson Resilience Scale (CD-RISC 10©) in breast cancer patients. Method: A sample of 169 Spanish women who had undergone surgery for breast cancer completed the CD-RISC 10©, along with questionnaires assessing life satisfaction, emotional intelligence, self-esteem, and positive and negative affect. Results: Confirmatory Factor Analysis supported a single-factor structure with adequate fit indices. Reliability was analysed by calculating McDonald’s omega coefficient, which yielded a value of .83. Validity evidence based on relationships with other variables was provided by positive and significant correlations between scores on the CD-RISC 10© and scores on emotional intelligence (clarity and repair), life satisfaction, self-esteem and positive affect, and by a negative and significant correlation with negative affect. The majority of these correlations were above |.50|. Conclusions: The CD-RISC 10© has satisfactory psychometric properties and is a suitable tool for measuring resilience in patients with cancer. The instrument is quick and easy to apply and may be used in both clinical and research contexts.  相似文献   
206.
This paper examines Romanian bioethics regulations for biomedical sciences, looking in particular at the genetics area as a source for conflict of interest. The analysis is focused on the organizational level, national regulations, the sources for generating conflicts of interest, and management of conflicts. Modern biotechnology and gene technology are among the key technologies of the twenty-first century. The application of gene technology for medical and pharmaceutical purposes is widely accepted by society, but the same cannot be said of the development and application of gene technology in agriculture and food processing. Because the use of a technology in the production and processing of food is regarded more sceptically than in the production of biomedical products, there can be areas of conflict in many cases when communication is undertaken about gene technology in the agro-food sector. Ethical concerns play an important factor in this, but a society’s attitude to a developing technology is an amalgam of many effects which are beyond ethics as such. This paper contains a study carried out by the author for the Romanian Association for Consumer Protection about the attitudes of consumers towards genetically modified (GM) foods. This study revealed that in Romania more than 98% of consumers did not know anything about GM foods and frequently were confused about the definitions of these terms. In conclusion, it is necessary to say that there is a low level of knowledge regarding biotechnology in Romania and this is an important reason why there is neither public acceptance of gene technology products nor is there a rejection. An earlier version of this paper was presented at an International Conference on “Conflict of Interest and its Significance in Science and Medicine” held in Warsaw, Poland on 5–6 April, 2002. Ioana Ispas, MD in Molecular Biology, is a scientific researcher and Member of the Romanian Association for Consumer Protection, NCP for FP5-Quality of life and management of living resources.  相似文献   
207.
This review paper examines the literature on psychosocial factors associated with adjustment to sickle cell disease and insulin-dependent diabetes mellitus in children through the framework of the transactional stress and coping (TSC) model. The transactional stress and coping model views adaptation to a childhood chronic illness as mediated by several psychosocial factors. This review examines the utility of the model in explaining adjustment in two different childhood diseases, identifies needed research and intervention targets, as well as highlights potential changes to the model. The major conclusions of this review suggest that, in addition to child-specific factors, family functioning is an area that interventions should address in sickle cell disease and insulin-dependent diabetes mellitus.  相似文献   
208.
Neuropsychological Aspects of Pediatric Sickle Cell Disease   总被引:2,自引:0,他引:2  
Sickle cell disease (SCD), a class of genetic disorders characterized by abnormal, sickled red blood cells, is a chronic illness that results in progressive cerebrovascular disease. Neurocognitive sequelae of clinically apparent cerebrovascular accidents in children with SCD are characterized by pervasive impairments, including decrements in general intellectual functioning, language and verbal abilities, visual-motor and visual-spatial processing, memory, academic achievement, and processing of subtle prosodic information. In contrast, subtle neurocognitive deficits in the areas of attention and concentration, executive function, and visual-motor speed and coordination appear to be associated with silent infarcts that are not necessarily detected on physical examination. Investigation of the disease course and associated neurocognitive sequelae suggest a disease-specific model of neuropsychological impairment. Recommendations are made for clinical and research efforts in the field of pediatric neuropsychology.  相似文献   
209.
The Colored Ecological and Genetic Relational Map (CEGRM) [pronounced see-gram] is a conceptual approach and tool for presenting information about family and nonkin relationships and stories about inherited diseases in a simple, understandable form. It combines information that can be derived from pedigrees, genograms, ecomaps, and social network analysis in a single, or series of, pictorial maps based on colors and shapes. The CEGRM is based on a social systems perspective, particularly emphasizing social exchange and resource theories. The CEGRM should be particularly useful in genetic counseling research with members of suspected cancer-risk families or families with other late-onset inherited diseases. A genetic counseling client comes with a social history and context as well as a genetic one. Client decision-making in terms of reproductive plans, therapeutic intervention, lifestyle behavior and sharing or withholding of genetic information frequently becomes enmeshed with preexisting psycho-social relationships among biological kin, affinal kin (in-laws) and fictive kin (friends who act as family). The CEGRM makes it easier to compare different types of social interactions between the client and his/her significant others and among family members on the same dimensions.  相似文献   
210.
人乳头瘤病毒与宫颈癌的关系及启示   总被引:1,自引:1,他引:0  
分子流行病学明确表明某些特定型别的人乳头瘤病毒(HPV)感染是浸润性宫颈癌和宫颈上皮内病变的主要致病原因。在HPV与宫颈癌的关系研究中无时无刻不渗透着马克思主义哲学原理,从哲学的角度去思考将使我们更科学、更透彻地理解两者的关系。  相似文献   
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