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71.
Cheryl L. L. Carling Doris Tove Kristoffersen Victor M. Montori Jeph Herrin Holger J. Schünemann Shaun Treweek Elie A. Akl Andrew D. Oxman 《PLoS medicine》2009,6(8)
Background
While different ways of presenting treatment effects can affect health care decisions, little is known about which presentations best help people make decisions consistent with their own values. We compared six summary statistics for communicating coronary heart disease (CHD) risk reduction with statins: relative risk reduction and five absolute summary measures—absolute risk reduction, number needed to treat, event rates, tablets needed to take, and natural frequencies.Methods and Findings
We conducted a randomized trial to determine which presentation resulted in choices most consistent with participants'' values. We recruited adult volunteers who participated through an interactive Web site. Participants rated the relative importance of outcomes using visual analogue scales (VAS). We then randomized participants to one of the six summary statistics and asked them to choose whether to take statins based on this information. We calculated a relative importance score (RIS) by subtracting the VAS scores for the downsides of taking statins from the VAS score for CHD. We used logistic regression to determine the association between participants'' RIS and their choice. 2,978 participants completed the study. Relative risk reduction resulted in a 21% higher probability of choosing to take statins over all values of RIS compared to the absolute summary statistics. This corresponds to a number needed to treat (NNT) of 5; i.e., for every five participants shown the relative risk reduction one additional participant chose to take statins, compared to the other summary statistics. There were no significant differences among the absolute summary statistics in the association between RIS and participants'' decisions whether to take statins. Natural frequencies were best understood (86% reported they understood them well or very well), and participants were most satisfied with this information.Conclusions
Presenting the benefits of taking statins as a relative risk reduction increases the likelihood of people accepting treatment compared to presenting absolute summary statistics, independent of the relative importance they attach to the consequences. Natural frequencies may be the most suitable summary statistic for presenting treatment effects, based on self-reported preference, understanding of and satisfaction with the information, and confidence in the decision.Clinical Trials Registration
ISRCTN85194921 Please see later in the article for the Editors'' Summary 相似文献72.
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74.
Integrative analyses of genetic variation in enzyme activities of primary carbohydrate metabolism reveal distinct modes of regulation in <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis> 下载免费PDF全文
75.
Anja C. Winger Marte Kanck Roar Kristoffersen Rune Knudsen 《Environmental Biology of Fishes》2008,83(1):117-123
The seasonal occurrence of the monogenean ectoparasite Gyrodactylus salaris Malmberg infecting Arctic charr, Salvelinus alpinus (L.) in the two rivers Skibotnelva and Signaldalselva in northern Norway was studied in the period from autumn 2003 to autumn
2005. Skibotnelva has been infected with the parasite since 1979, and treated with rotenone twice. Most likely resident Arctic
charr avoided the rotenone treatment in small tributary streams, and thus was the source of the repeated re-infection of this
river. G. salaris was first recorded in Signaldalselva in the year 2000 and it is still untreated. Unlike Atlantic salmon, which is highly
susceptible to G. salaris, Arctic charr can display a wide range of host-responses to G. salaris infections. Arctic charr were sampled by electro fishing with a total sample of 681 Arctic charr. The results from this study
demonstrate an evident seasonal dynamic in G. salaris infection in charr in both rivers. Parasite intensities fluctuated with the rise and fall in temperature through the year,
with an autumn high and spring low. There was a significantly lower prevalence and mean intensity of G. salaris in Skibotnelva than in Signaldalselva. There were also a lower prevalence and intensity of G. salaris in the older than in the youngest charr. The different history of infection and treatment in the two rivers might be the
underlying cause of these observed dissimilarities. The current study indicates that Arctic charr is a good natural host for
G. salaris. 相似文献
76.
Kutryk MJ Wardeh AJ Knook AH Foley DP Giessen WJ Hamburger JN Brand Mv Feyter PJ Becker GJ Serruys PW 《International journal of cardiovascular interventions》1999,2(3):163-169
BACKGROUND: Coronary stents have been used with increasing frequency and in increasingly complex coronary disease. A new 316 LVM stainless steel coronary stent, the R Stent, has been designed to provide maximum flexibility for tracking and high radial strength post-deployment. PURPOSE: To assess the clinical feasibility of the R Stent in a tertiary referral population of patients with coronary heart disease. Specific objectives are to assess the R Stent's deployment success, angiographic and procedural success (<20% residual stenosis and >TIMI 2 flow), safety (absence of complications), and 30-day clinical success (angiographic/procedural success plus no major adverse coronary events). METHODS: Between April and November 1998, stent deployment was attempted in 27 patients with stable (46%) or unstable (54%) angina pectoris who qualified for percutaneous transluminal coronary angioplasty. Eighty per cent of patients had a pre-existing history of myocardial infarction, coronary bypass surgery or percutaneous transluminal coronary angioplasty, and several of the lesions were anatomically complex (totally occluded, n 32; thrombus present, n 32; heavily calcified, n 33; ostial, n 31; >20 mm long, n 39; angulation >45 degrees, n 37). Lesions in aortocoronary saphenous vein grafts were excluded. Adjunctive medical management included intraprocedural aspirin and heparin and post-procedural aspirin and ticlopidine. After deployment, patients were followed up in the hospital and at 30 days post procedure. RESULTS: Stent deployment was achieved in 32 of 33 attempts (26 of 27 patients). There was one deployment failure in a long, calcified ostial and proximal left coronary lesion. In the 26 successful deployments, TIMI 3 flow was achieved. One other patient experienced a painless increase in creatine kinase to 375 (CK-MB of 59) at 12 h without ECG changes. At 30 days, there were no deaths, no myocardial infarctions, no subacute thromboses, no repeat interventions, no bypass surgeries and no bleeding complications. Only the patient with post-procedural CK-MB elevation experience recurrence of CCS class 2 angina within the 30 days. CONCLUSION: The R Stent is a promising new device for the treatment of complex coronary heart disease. A larger, more broadly-based study is warranted. 相似文献
77.
Kristoffersen P Jensen GB Gerdes K Piskur J 《Applied and environmental microbiology》2000,66(12):5524-5526
The potential of a bacterial toxin-antitoxin gene system for use in containment control in eukaryotes was explored. The Escherichia coli relE and relB genes were expressed in the yeast Saccharomyces cerevisiae. Expression of the relE gene was highly toxic to yeast cells. However, expression of the relB gene counteracted the effect of relE to some extent, suggesting that toxin-antitoxin interaction also occurs in S. cerevisiae. Thus, bacterial toxin-antitoxin gene systems also have potential applications in the control of cell proliferation in eukaryotic cells, especially in those industrial fermentation processes in which the escape of genetically modified cells would be considered highly risky. 相似文献
78.
Madelaine Norstr?m Anja Br?then Kristoffersen Franziska Sophie G?rlach Karin Nyg?rd Petter Hopp 《PloS one》2015,10(8)
In order to facilitate foodborne outbreak investigations there is a need to improve the methods for identifying the food products that should be sampled for laboratory analysis. The aim of this study was to examine the applicability of a likelihood ratio approach previously developed on simulated data, to real outbreak data. We used human case and food product distribution data from the Norwegian enterohaemorrhagic Escherichia coli outbreak in 2006. The approach was adjusted to include time, space smoothing and to handle missing or misclassified information. The performance of the adjusted likelihood ratio approach on the data originating from the HUS outbreak and control data indicates that the adjusted approach is promising and indicates that the adjusted approach could be a useful tool to assist and facilitate the investigation of food borne outbreaks in the future if good traceability are available and implemented in the distribution chain. However, the approach needs to be further validated on other outbreak data and also including other food products than meat products in order to make a more general conclusion of the applicability of the developed approach. 相似文献
79.
L. Kristoffersen A. Bugge E. Lundanes L. Slrdal 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1999,734(2):141
A method for the simultaneous determination of the three selective serotonin reuptake inhibitors (SSRIs) citalopram, fluoxetine, paroxetine and their metabolites in whole blood and plasma was developed. Sample clean-up and separation were achieved using a solid-phase extraction method with C8 non-endcapped columns followed by reversed-phase high-performance liquid chromatography with fluorescence and ultraviolet detection. The robustness of the solid-phase extraction method was tested for citalopram, fluoxetine, paroxetine, Cl-citalopram and the internal standard, protriptyline, using a fractional factorial design with nine factors at two levels. The fractional factorial design showed two significant effects for paroxetine in whole blood. The robustness testing for citalopram, fluoxetine, Cl-citalopram and the internal standard revealed no significant main effects in whole blood and plasma. The optimization and the robustness of the high-performance liquid chromatographic separation were investigated with regard to pH and relative amount of acetonitrile in the mobile phase by a central composite design circumscribed. No alteration in the elution order and no significant change in resolution for a deviation of ±1% acetonitrile and ±0.3 pH units from the specified conditions were observed. The method was validated for the concentration range 0.050–5.0 μmol/l with fluorescence detection and 0.12–5.0 μmol/l with ultraviolet detection. The limits of quantitation were 0.025 μmol/l for citalopram and paroxetine, 0.050 μmol/l for desmethyl citalopram, di-desmethyl citalopram and citalopram-N-oxide, 0.12 μmol/l for the paroxetine metabolites by fluorescence detection, and 0.10 μmol/l for fluoxetine and norfluoxetine by ultraviolet detection. Relative standard deviations for the within-day and between-day precision were in the ranges 1.4–10.6% and 3.1–20.3%, respectively. Recoveries were in the 63–114% range for citalopram, fluoxetine and paroxetine, and in the 38–95% range for the metabolites. The method has been used for the analysis of whole blood and plasma samples from SSRI-exposed patients and forensic cases. 相似文献
80.
Survival of vegetation on soil-capped mining wastes is often impaired during dry seasons due to the limited amount of water stored in the shallow soil capping. Growth and survival of Rhodes grass (Chloris gayana) during soil drying on various layered capping sequences constructed of combinations of topsoil, subsoil, seawater-neutralised residue sand and low grade bauxite was determined in a glasshouse. The aim was to describe the survival of Rhodes grass in terms of plant and soil water relationships. The soil water characteristic curve and soil texture analysis was a good predictor of plant survival. The combination of soil with a high water holding capacity and low soil water diffusivity (e.g. subsoil with high clay contents) with soil having a high water holding capacity and high diffusivity (e.g. residue sand) gave best survival during drying down (up to 88 days without water), whereas topsoil and low grade bauxite were unsuitable (plants died within 18–39 days). Clayey soil improved plant survival by triggering a water stress response during peak evaporative water demand once residue sand dried down and its diffusivity fell below a critical range. Thus, for revegetation in seasonally dry climates, soil capping should combine one soil with low diffusivity and one or more soils with high total water holding capacity and high diffusivity. 相似文献