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31.
Objective To develop and evaluate the effectiveness of a breast cancer prevention decision aid for women aged 50 and older at higher risk of breast cancer. Design Pre‐test–post‐test study using decision aid alone and in combination with counselling. Setting Breast Cancer Risk Assessment Clinic. Participants Twenty‐seven women aged 50–69 with 1.66% or higher 5‐year risk of breast cancer. Intervention Self‐administered breast cancer prevention decision aid. Main outcome measures Acceptability; decisional conflict; knowledge; realistic expectations; choice predisposition; intention to improve life‐style practices; psychological distress; and satisfaction with preparation for consultation. Results The decision aid alone, or in combination with counselling, decreased some dimensions of decisional conflict, increased knowledge (P < 0.01), and created more realistic expectations (P < 0.01). The aid in combination with counselling, significantly reduced decisional conflict (P < 0.01) and psychological distress (P < 0.02), helped the uncertain become certain (P < 0.02), and increased intentions to adopt healthier life‐style practices (P < 0.03). Women rated the aid as acceptable, and both women and practitioners were satisfied with the effect it had on the counselling session. Conclusion The decision aid shows promise as a useful decision support tool. Further research should compare the effect of the decision aid in combination with counselling to counselling alone.  相似文献   
32.
This study assesses the relative importance of history, examination and investigations in paediatric diagnosis, in the Paediatric Out-patient Department of the Central Middlesex Hospital, London, by means of a questionnaire-based record of 94 consecutive referrals. A diagnosis identical to the final diagnosis was made in 76% of referrals after taking a history. The general practitioner had proposed a diagnosis in 45% in the referral letter. Clinical examination changed the diagnosis in only 15% but increased diagnostic confidence in 33%. Ninety-one per cent of cases were diagnosed without recourse to investigations. Forty-two per cent of children referred had investigations performed. In the majority of paediatric cases the provisional diagnosis reached after taking a history was identical to that after examination or results of investigations were known. Although examination provided a final diagnosis in only 15% of all cases it played an important role in adding confidence in 33%. More educational effort should therefore be directed at clinical history-taking skills and the subsequent purpose of examination.  相似文献   
33.
Objective  To explore prospectively women's decision making regarding mode of delivery after a previous caesarean section.
Main outcome measures  The evolution of decision making, women's participation in decision making, and factors affecting decision making.
Design and methods  A qualitative study using diaries, observations and semi-structured interviews. Data were analysed thematically from both a longitudinal and a cross-sectional perspective.
Setting  An antenatal unit in a large teaching hospital in Scotland and participants' homes.
Sample  Twenty-six women who had previously had a caesarean section for a nonrecurrent cause.
Results  Women were influenced by their own previous experiences and expectations, and the final decision on mode of delivery often developed during the course of the pregnancy. Most acknowledged that any decision was provisional and might change if circumstances necessitated. Despite a universal desire to be involved in the process, many women did not participate actively and were uncomfortable with having responsibility for decision making. Feelings about the amount and quality of the information received regarding delivery options varied greatly, with many women wishing for information to be tailored to their individual clinical circumstances and needs. In contrast to the impression created in the media, there was no evidence of clear preferences or strong demands for elective caesarean section.
Conclusion  Women who have had a previous caesarean section do not usually have firm ideas about mode of delivery. They look for targeted information and guidance from medical personnel based on their individual circumstances, and some are unhappy with the responsibility of deciding how to deliver in the current pregnancy.  相似文献   
34.
This study sought to measure the effect of pulmonary function testing (PFT) data on the decisions made by generalist physicians in the management of chronic obstructive pulmonary disease (COPD). 148 physicians were randomly assigned to two groups, both of which were asked to manage two identical fictitious but representative cases of COPD, which included history, physical, x-ray, and laboratory results. The experimental group received PFT results in addition. No significant difference was noted between the two groups in management based on availability of PFT data. The optimum utility of PFT data in the management of COPD may be exaggerated and has yet to be determined. Received from the Department of Medicine, Division of General Internal Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin. Presented at the Annual Scientific Meeting of the American College of Chest Physicians, October 28, 1992, Chicago, Illinois.  相似文献   
35.
基于混合遗传算法的心脏病决策支持系统研究   总被引:1,自引:0,他引:1  
将遗传算法和 BP算法相结合 ,建立了一个基于混合遗传算法的心脏病决策支持系统来鉴别诊断五种常见心脏病 (冠心病 ,高血压性心脏病 ,风湿性心脏病 ,慢性肺原性心脏病和先天性心脏病 )。一个含有 35 2份心脏病的数据库用来构建和测试了该系统。实验结果表明 ,构建的系统对这五种心脏病均有较好的诊断识别率 ,系统的平均识别准确性达 90 .6 % ,各疾病的用户准确性和程序准确性均大于 85 .0 % ,表现出良好的心脏病的临床诊断决策支持能力  相似文献   
36.
OBJECTIVE: The GRIF automated feedback system produces real-time comments on the appropriateness of diagnostic tests ordered by general practitioners (GPs) based on recommendations from accepted national and regional practice guidelines. We investigated the experiences of GPs with this system and, more specifically, with the recommendations produced by the system as well as their views on using this system in daily practice. SETTING: We tested the GRIF system in an experiment in a laboratory setting and in a daily practice trial. STUDY PARTICIPANTS: General practitioners. INTERVENTION: In the laboratory experiment, GPs used the GRIF system to assess the appropriateness of 30 request forms. Each of the GPs was confronted with requests they had submitted to the diagnostic unit of the hospital in the past. In the field trial, the GRIF system was applied during patient consultations for 1 year. MAIN OUTCOME MEASURES: We measured GPs' satisfaction with the system using a questionnaire, and also conducted group discussions (in the laboratory experiment) and in-depth interviews (in the field trial) to elicit GPs' opinions of and experiences with the system. In addition, we explored GPs' reasons for not accepting the comments offered by the GRIF system. RESULTS: The results show that the GPs in the laboratory experiment had more positive attitudes towards the system compared with participants in the field trial. All discussion groups and most of the GPs in the field trial regarded receiving the immediate feedback during the test ordering process as an important advantage. The most frequently mentioned reason to reject the recommendation was disagreement with the content and/or the recommendations in the practice guidelines. CONCLUSION: Apart from securing agreement on guideline content, a prerequisite for using GRIF in daily practice on a large scale is that more attention is paid to promotion of the guidelines and their adoption, and stimulation of a positive attitude towards the practice guidelines among the users.  相似文献   
37.
应用荧光逆行标记分别与荧光组化(FAGLU)和AChE-药理组化相结合技术,研究了树鼩中脑腹侧被盖区向尾状核头部的DOPA能和ACHE-阳性纤维投射。结果表明:树鼩中脑腹侧被盖区除分别向同侧和对侧尾状核头部发出DOPA能纤维投射外,还向同侧尾状核头部发出AChE阳性投村纤维;此外,腹侧被盖区存在着向双侧尾核头部发出分叉投射纤维的DOPA能细胞。  相似文献   
38.
Bayesian decision theoretic approaches (BDTAs) have been widely studied in the literature as tools for designing and conducting phase II clinical trials. However, full Bayesian approaches that consider multiple endpoints are lacking. Since the monitoring of toxicity is a major goal of phase II trials, we propose an adaptive group sequential design using a BDTA, which characterizes efficacy and toxicity as correlated bivariate binary endpoints. We allow trade‐off between the two endpoints. Interim evaluations are conducted group sequentially, but the number of interim looks and the size of each group are chosen adaptively based on current observations. We utilize a loss function consisting of two components: the loss associated with accruing, treating, and monitoring patients, and the loss associated with making incorrect decisions. The performance of our Bayesian modeling, and the operating characteristics of decision rules under a wide range of loss function parameters are evaluated using seven scenarios in a simulation study. Our method is illustrated in the context of a single‐arm phase II trial of bevacizumab, gemcitabine, and oxaliplatin in patients with metastatic pancreatic adenocarcinoma. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
39.
目的 建立基于临床数据的慢性乙肝患者典型证候的诊断模型,探索与慢性乙肝典型证候相关的症状、体征和实验室指标组合。 方法 对1 004例慢性乙肝患者进行证候学调查和实验室检测,包括 88项症状、舌脉象、20项体征和 14项实验室指标。然后选取典型证候的临床数据,联合采用Logistic回归、决策树、贝叶斯网络方法进行数据分析,构建能够有效区分不同证候的诊断模型。 结果 1 004例慢性乙肝患者中最为典型的证候为肝胆湿热证(340例,占33.86%)与肝郁脾虚证(366例,占36.45%)。首先采用Logistic回归分析得到具有统计学意义的16项症状与体征及3项实验室指标,然后采用决策树方法构建能够区分肝胆湿热证、肝郁脾虚证的诊断模型(辨证诊断准确率=74.36%),发现苔白、淡红舌、巩膜黄染、两目干涩、丙氨酸转氨酶(ALT)和 HBeAg是鉴别两证型的有效指标组合。采用贝叶斯网络分析的结果也验证了上述指标的重要性。 结论 本文建立了一种能够有效判别慢性乙肝患者肝胆湿热证、肝郁脾虚证的决策树诊断模型,为将基于经验的中医辨证转向基于数据模型的辨证提供了方法,有助于促进证候的客观化诊断。  相似文献   
40.
The present study assessed the effects of problem-solving (D'Zurilla & Goldfried, 1971) training on two problem-solving tasks. Sixty-one subjects were assigned randomly to and trained in one of the following groups: general orientation (GO)-problem definition (PD)-generation of alternatives (GA)-decision making (DM), GO-PD-GA, GO-PD-DM, GO-GA-DM, GO, and a control group. The six groups did not differ significantly at pretesting on the measures of selecting the best alternative solution and describing problem-solving behaviors used to solve problems. Training was significantly effective on selecting the best alternative solution for all groups compared with the control group at the time of posttesting. The GO-PD-GA-DM and GO-PD-DM groups described significantly more problem-solving behaviors than the GO-PD-GA, GO-GA-DM, and GO groups. All five treatment groups performed significantly better than the control group at the time of post-testing. At follow-up 1 month after posttesting, groups trained with the PD component selected significantly better alternatives than the groups without PD training. Groups trained with the DM component described significantly more problem-solving behaviors at follow-up than the groups trained without the DM component.  相似文献   
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