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排序方式: 共有1308条查询结果,搜索用时 31 毫秒
1.
ABSTRACTIn clinical trials, selection of appropriate study endpoints is critical for an accurate and reliable evaluation of safety and effectiveness of a test treatment under investigation. In practice, however, there are usually multiple endpoints available for measurement of disease status and/or therapeutic effect of the test treatment under study. For example, in cancer clinical trials, overall survival, response rate, and/or time to disease progression are usually considered as primary clinical endpoints for evaluation of safety and effectiveness of the test treatment under investigation. Once the study endpoints have been selected, sample size required for achieving a desired power is then determined. It, however, should be noted that different study endpoints may result in different sample sizes. In practice, it is usually not clear which study endpoint can best inform the disease status and measure the treatment effect. Moreover, different study endpoints may not translate one another although they may be highly correlated one another. In this article, we intend to develop an innovative endpoint namely therapeutic index based on a utility function to combine and utilize information collected from all study endpoints. Statistical properties and performances of the proposed therapeutic index are evaluated theoretically. A numerical example concerning a cancer clinical trial is given to illustrate the use of the proposed therapeutic index. 相似文献
2.
Cost‐Effectiveness and Cost‐Utility Analysis of Spinal Cord Stimulation in Patients With Failed Back Surgery Syndrome: Results From the PRECISE Study
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Furio Zucco MD Roberta Ciampichini MSc Angelo Lavano MD Amedeo Costantini MD Marisa De Rose MD Paolo Poli MD Gianpaolo Fortini MD Laura Demartini MD Enrico De Simone MD Valentino Menardo MD Piero Cisotto MD Mario Meglio MD Luciana Scalone PhD Lorenzo G. Mantovani DSc 《Neuromodulation》2015,18(4):266-276
3.
天津医科大学第三医院抗生素类药物的利用分析 总被引:4,自引:0,他引:4
目的:对抗生素类药物利用状况进行分析,以考察应用情况,促进用药合理性,方法:查阅药库2000年药品购入目录,采用药物利用状况分析法,对抗生素用药频度和药物费用等进行分析。结果:该院应用的抗生素主要为头孢菌素,喹诺酮类;DDDs排序靠前的是诺氟沙星,羟氨苄青霉素和复方新诺明等。结论:该院用药基本合理,但水平较低。 相似文献
4.
Phoebe S. Y. Lo Michael C. F. Tong Dennis A. Revicki Ching Chyi Lee John K. S. Woo Henry C. K. Lam C. Andrew van Hasselt 《Quality of life research》2006,15(5):877-887
Background: The Rhinitis Symptom Utility Index (RSUI), originally developed in the United States, consists of a patient-preference weighting
scheme and a 10-item questionnaire measuring the severity and frequency of rhinitis related symptoms over a 14-day period.
This study aimed to determine whether the Chinese RSUI could adopt the US-based multi-attribute utility function (MAUF) in
scoring rhinitis symptoms. Methods: In a Hong Kong study, 116 Chinese adults with allergic rhinitis completed the RSUI questionnaire and 36-item Short-Form
Health Survey (SF-36) after they had been seen by two otorhinolaryngologists for disease-severity ratings. Respondents then
completed computer-administered direct preference measures, i.e., visual analogue scale (VAS) and standard gamble (SG) assessments.
The VAS and SG data were used to estimate a MAUF for the Chinese-based RSUI. Results: The derived MAUF was somewhat different than the one developed for the US RSUI. Test–retest reliability for the Chinese
RSUI was satisfactory (ICC = 0.71, p<0.001). Scores differentiated among cases with mild, moderate, and severe symptoms (p<0.001); and between those who did and did not require medications to control symptoms (p = 0.031). Findings were significantly correlated with SF-36 domain scores (r = 0.19 to 0.37; p=0.041 to <0.001). When the US-based scoring function was applied to the Chinese subjects, the resulting mean RSUI score was
significantly lower (p<0.001). Comparisons between directly measured VAS and SG scores between the US and Chinese samples, demonstrated significant
differences (all p<0.05), with the US subjects consistently rating rhinitis symptoms as worse than Chinese subjects. Conclusions: The Chinese RSUI has good measurement properties that reflect patient preferences from the Chinese. Results suggest that
there are differences in preference rating between US and Chinese subjects and that use of the US-based preference function
for the RSUI would bias the measurement of rhinitis symptom outcomes in Chinese subjects. 相似文献
5.
Maria Pia Francescato P. Cok O. Radillo B. de Bernard 《Journal of human nutrition and dietetics》1988,1(5):321-327
A computer-assisted method for the registration of food intakes in real time according to a concise and simple procedure was subjected to a series of controls in order to assess precision. The method employs the 'portion' of a composite dish as unit of measure. The constancy of the portion was tested. The results show that the recipes of the diet of a subject may be stored and utilized in deferred time without loss of precision: data to be recorded in real time are then very limited. The length of period of analysis was also studied. The time of investigation should not be shorter than two weeks to obtain precise information on the feeding habits of an individual subject, whereas for a group of subjects the diary of a single day provides information of sufficient precision. 相似文献
6.
I-Chan Huang Richard J. Willke Mark J. Atkinson William R. Lenderking Constantine Frangakis Albert W. Wu 《Quality of life research》2007,16(6):1065-1072
Background Most US studies that estimate EQ-5D index score generally apply the UK preference weights. We compared the validity of a
newly-developed US weights to the UK weights for use of EQ-5D as a measure of health-related quality of life. Methods Data were collected from a randomized clinical trial for patients with HIV (n = 1,126) in the US. Convergent validity was examined by comparing Pearson correlations of EQ-5D index scores with the MOS-HIV
Health Survey scale scores and Physical and Mental Health Summary (PHS, MHS) scores using the US and UK weights. Known-groups
validity of EQ-5D US versus UK index scores was compared using clinical variables (CD4+ cell count and HIV viral load), and
the MOS-HIV PHS and MHS. Score changes in the EQ-5D index from baseline to week 50 were examined using effect size (ES) estimates.
Results The mean EQ-5D index scores was slightly higher using US weights than UK weights (0.87 vs. 0.84, respectively). The correlation
coefficient for EQ-5D utilities using the US and UK weights was 0.98. The correlations of EQ-5D index scores with the MOS-HIV
scores were moderate and similar using the US and UK weights. The EQ-5D index scores discriminated equally well for both versions
between levels of CD4+ count, HIV viral load, and PHS and MHS scores (P < 0.05), suggesting equivalent known-groups validity. The changes in EQ-5D index scores from baseline to week 50 were similar
for both versions (ES: 0.21 vs. 0.22 for US and UK, respectively), suggesting equivalent responsiveness to score changes.
Conclusions EQ-5D index scores generated using UK and US preference weights showed equivalent psychometric properties. For assessing
treatment benefit in a single population, the use of either the UK or US weights as a measure of HRQOL will not change inferences.
However, for comparisons across US and UK populations, the choice between these two weights should be based on their relevance
to the study population. 相似文献
7.
We evaluated the influence of individually estimated portion sizes on the estimate of nutrient related risk of colorectal cancer, using data from a Portuguese hospital based case-control study on diet and colorectal cancer. A total of 100 patients with colorectal adenocarcinoma (aged 15-92 years) and 211 controls (aged 36-89 years) were included. Two data sets were created for nutrient analysis, the first one allowed estimates of food intake using data on portion size as collected with visual aids during the interview. The second estimate substituted respondents' estimate with a standard portion size, as used in the semi-quantitative (SQ) food frequency approach. The two analytic approaches yielded similar energy and nutrient intakes in cases and controls. The percent range of concordance is acceptable, in the same quartile varying from 44 to 82% (mean: 56%) and very good in the same or adjacent (+/-1) quartile (mean: 91%, range: 85-97%). The two estimates lead to a similar pattern of multivariate odd's ratio, however the SQ estimates resulted in more significant findings. We conclude that little extra information is gained by including individual portion size information when assessing diet-related risk of colorectal cancer. 相似文献
8.
常规医疗设备招标存在问题的思考和对策--决策学多属性效用理论的实践探索 总被引:1,自引:0,他引:1
通过对常规医疗设备招标存在问题的思考,采用决策学多属性效用理论作为一种对策方法,并在实际操作中进行了尝试探索,以取得更好的效果. 相似文献
9.
F. VanderWerf Majid Aramideh Jan A. Otto Bram W. Ongerboer de Visser 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,121(4):433-441
Functionally and anatomically, the orbicularis oculi (OO) muscle can be subdivided in a pretarsal, a preseptal, and an orbital
portion. In the rhesus monkey, fluorescent and neuronal retrograde tracing experiments were performed in the pretarsal or
the orbital portion of the OO muscle, or both, using fast blue, diamidino yellow, and wheat germ agglutinin-horseradish peroxidase
as tracers. The preseptal portion was not investigated because of close anatomical relationships to the other portions. It
was found that motoneurons innervating the OO muscle are located exclusively within the intermediate subnucleus of the motor
facial nucleus. The upper pretarsal motoneurons show a specific distribution in the dorso-rostral border area of the intermediate
subnucleus, representing a dome-like organization, while lower pretarsal motoneurons are situated more ventrally in the adjacent
area. The pretarsal motoneurons are all located dorsally in the rostral half and the upper part of the caudal half of the
intermediate subnucleus. The upper pretarsal portion is subserved by about one third of the total intermediate motoneuron
population. The size of the upper pretarsal motoneurons is similar to that of the motoneurons of the lower pretarsal portion
of the OO muscle and falls, for the vast majority, into the large motoneuronal range. Motoneurons belonging to the upper and
lower orbital portions are located ventrally and are more randomly distributed in the rostral half of the intermediate subnucleus.
The size of orbital motoneurons varies from small to large. The large fraction of pretarsal motoneurons may reflect the specific
function of the upper pretarsal portion during rapid and highly coordinated movements of the eyelids in different types of
blinking.
Received: 18 September 1997 / Accepted: 13 March 1998 相似文献
10.
IgG inhibits the increase of platelet-associated C3 stimulated by anti-platelet antibodies 总被引:1,自引:0,他引:1
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S. Nomura Y. Miyazaki T. Miyake K. Yamaguchi H. Kido T. Kawakatsu T. Fukuroi H. Kagawa M. Suzuki M. Yanabu T. Kokawa 《Clinical and experimental immunology》1993,93(3):452-455
We investigated the increase of platelet-associated IgG and complement component 3 (C3) caused by the in vitro action of anti-platelet MoAbs, and the effect of mouse and human IgG on these events. Anti-glycoprotein IIb/IIIa and anti-glycoprotein Ib MoAbs caused a slight increase of C3, but not of platelet-associated IgG. In contrast, anti-CD9 and anti-Fcγ II receptor MoAbs caused an increase of both platelet-associated C3 and IgG. In particular, three MoAbs which activated the complement system caused a marked increase of C3. When platelet-rich plasma was treated with aspirin and prostaglandin E1 before incubation with antibodies, the increase of platelet-associated IgG was inhibited in all cases. In contrast, the increase of platelet-associated C3 was scarcely influenced. These results suggest that the binding to platelets of platelet-activating antibodies caused the increase expression of IgG molecules on the platelet surface and a possible increase of platelet-associated IgG. However, the increase of platelet-associated C3 appeared to depend on specific characteristics of the antibodies tested, such as a complement-activating effect. In addition, intact mouse or human IgG inhibited the increase of platelet-associated C3 caused by complement-activating antibodies, while F(ab')2 mouse or human IgG had no such effect. This suggested that the Fc portion of IgG may block the increase of C3 mediated by anti-platelet antibodies. 相似文献