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Decision Points (decision + point)
Selected AbstractsNoninferiority and equivalence designs: Issues and implications for mental health researchJOURNAL OF TRAUMATIC STRESS, Issue 5 2008Carolyn J. Greene The terms noninferiority and equivalence are often used interchangeably to refer to trials in which the primary objective is to show that a novel intervention is as effective as the standard intervention. The use of these designs is becoming increasingly relevant to mental health research. Despite the fundamental importance of these designs, they are often poorly understood, improperly applied, and subsequently misinterpreted. In this article, the authors explain noninferiority and equivalence designs and key methodological and statistical considerations. Decision points in using these designs are discussed, such as choice of control condition, determination of the noninferiority margin, and calculation of sample size and power. With increasing utilization of these designs, it is critical that researchers understand the methodological issues, advantages, disadvantages, and related challenges. [source] An algorithm for evaluating the ethics of a placebo-controlled trialINTERNATIONAL JOURNAL OF CANCER, Issue 5 2001Robert J. Amdur M.D. Abstract The purpose of this article is to clarify the decision points that are important to consider when evaluating the ethics of a placebo-controlled trial. The ethical requirements for research involving human subjects are reviewed, and the rationale for and potential problems with concomitant placebo control are explained. A series of case discussions are used to illustrate each decision point. The critical decision points in the evaluation of the ethics of a placebo-controlled trial are as follows: (i) Is placebo being used in place of standard therapy? (ii) Is standard therapy likely to be effective? (iii) Is the toxicity of standard therapy such that patients routinely refuse this treatment? (iv) Could the use of placebo result in severe suffering or irreversible harm? (v) Is the variability in the placebo response such that it is reasonable to consider other options for the control group? (vi) Would a reasonable person with an average degree of altruism and risk aversiveness agree to participate in this study? The algorithm presented in this article gives researchers and research monitors (such as Institutional Review Board members) the tools they need to evaluate the ethics of a study that uses concomitant placebo control. © 2001 Wiley-Liss, Inc. [source] A social agent pedestrian modelCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2008Andrew Park Abstract This paper presents a social agent pedestrian model based on experiments with human subjects. Research studies of criminology and environmental psychology show that certain features of the urban environment generate fear in people, causing them to take alternate routes. The Crime Prevention Through Environmental Design (CPTED) strategy has been implemented to reduce fear of crime and crime itself. Our initial prototype of a pedestrian model was developed based on these findings of criminology research. In the course of validating our model, we constructed a virtual environment (VE) that resembles a well-known fear-generating area where several decision points were set up. 60 human subjects were invited to navigate the VE and their choices of routes and comments during the post interviews were analyzed using statistical techniques and content analysis. Through our experimental results, we gained new insights into pedestrians' behavior and suggest a new enhanced and articulated agent model of a pedestrian. Our research not only provides a realistic pedestrian model, but also a new methodology for criminology research. Copyright © 2008 John Wiley & Sons, Ltd. [source] Process Considerations for Trolling Borehole Flow LogsGROUND WATER MONITORING & REMEDIATION, Issue 3 2006Phil L. Oberlander Horizontal hydraulic conductivity with depth is often understood only as a depth-integrated property based on pumping tests or estimated from geophysical logs and the lithology. A more explicit method exists for determining hydraulic conductivity over small vertical intervals by collecting borehole flow measurements while the well is being pumped. Borehole flow rates were collected from 15 deep monitoring wells on the Nevada Test Site and the Nevada Test and Training Range while continuously raising and lowering a high-precision impeller borehole flowmeter. Repeated logging passes at different logging speeds and pumping rates typically provided nine unique flow logs for each well. Over 60 km of borehole flow logs were collected at a 6.1-cm vertical resolution. Processing these data necessitated developing a methodology to delete anomalous values, smooth small-scale flow variations, combine multiple borehole flow logs, characterize measurement uncertainty, and determine the interval-specific lower limit to flow rate quantification. There are decision points in the data processing where judgment and ancillary analyses are needed to extract subtle hydrogeologic information. The analysis methodology indicates that processed measurements from a high-precision trolling impeller flowmeter in a screened well can confidently detect changes in borehole flow rate of ,0.7% of the combined trolling and borehole flow rate. An advantage of trolling the flowmeter is that the impeller is nearly always spinning as it is raised and lowered in the well and borehole flow rates can be measured at lower values than if measurements were taken while the flowmeter was held at a fixed depth. [source] An algorithm for evaluating the ethics of a placebo-controlled trialINTERNATIONAL JOURNAL OF CANCER, Issue 5 2001Robert J. Amdur M.D. Abstract The purpose of this article is to clarify the decision points that are important to consider when evaluating the ethics of a placebo-controlled trial. The ethical requirements for research involving human subjects are reviewed, and the rationale for and potential problems with concomitant placebo control are explained. A series of case discussions are used to illustrate each decision point. The critical decision points in the evaluation of the ethics of a placebo-controlled trial are as follows: (i) Is placebo being used in place of standard therapy? (ii) Is standard therapy likely to be effective? (iii) Is the toxicity of standard therapy such that patients routinely refuse this treatment? (iv) Could the use of placebo result in severe suffering or irreversible harm? (v) Is the variability in the placebo response such that it is reasonable to consider other options for the control group? (vi) Would a reasonable person with an average degree of altruism and risk aversiveness agree to participate in this study? The algorithm presented in this article gives researchers and research monitors (such as Institutional Review Board members) the tools they need to evaluate the ethics of a study that uses concomitant placebo control. © 2001 Wiley-Liss, Inc. [source] Transitioning the patient with acute coronary syndrome from inpatient to primary care,JOURNAL OF HOSPITAL MEDICINE, Issue S4 2010FACPE, Tomás Villanueva DO Abstract Patients with acute coronary syndrome (ACS) undergo several transitions in care throughout the hospital stay, from prehospitalization to the postdischarge period when patients return to primary care. Hospitalist core competencies promote safe transitions in care for patients with ACS, including hospital discharge. These competencies also highlight the central role of the hospitalist in facilitating the continuity of care and as a key link between the patient and the primary care provider (PCP). Core competencies address key decision points and processes that occur during hospitalization for ACS including the initial evaluation and risk stratification, medication reconciliation, and discharge planning. Discharge is a crucial transition and one where hospitalists can both facilitate the transition to primary care and improve adherence to quality measures established for ACS. Poor communication during discharge reportedly results in postdischarge adverse events, most often related to medications and lack of follow-up related to pending test results. Standards for a safe discharge such as Project RED (Re-Engineered Discharge), initiatives to improve outcomes after discharge like Project BOOST (Better Outcomes for Older Adults Through Safe Transitions), and adaptive tools including the ACS Transitions Tool support timely and accurate communication of complex information between the hospitalist, the PCP, and the patient. While the role of hospitalists is evolving, it is clear that they have a central role in ensuring safe transitions in care for ACS. Journal of Hospital Medicine 2010;5:S8,S14. © 2010 Society of Hospital Medicine. [source] Comparison of a miniaturized shake-flask solubility method with automated potentiometric acid/base titrations and calculated solubilitiesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 1 2005A. Glomme Abstract Solubility is one of the most important parameters for lead selection and optimization during drug discovery. Its determination should therefore take place as early as possible in the process. Because of the large numbers of compounds involved and the very low amounts of each compound available in the early development stage, it is highly desirable to measure the solubility with as little compound as possible and to be able to improve the throughput of the methods used. In this work, a miniaturized shake-flask method was developed and the solubility results were compared with those measured by semiautomated potentiometric acid/base titrations and computational methods for 21 poorly soluble compounds with solubilities mostly in the range 0.03,30 ,g/mL. The potentiometric method is very economical (approximately 100 ,g of a poorly soluble compound is needed) and is able to create a pH/solubility profile with one single determination, but is limited to ionizable compounds. The miniaturized shake-flask method can be used for all compounds and a wide variety of media. Its precision and throughput proved superior to the potentiometric method for very poorly soluble compounds. Up to 20 compounds a week can be studied with one set-up. Calculated solubility data seem to be sufficient for a first estimate of the solubility, but they cannot currently be used as a substitute for experimental measurements at key decision points in the development process. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 94:1,16, 2005 [source] How to Achieve Confidence in Drug Discovery and Development: Managing Risk (from a Reductionist to a Holistic Approach)CHEMMEDCHEM, Issue 6 2009Annette Bakker Dr. Abstract Confidence in mechanism: Creating a more holistic understanding of disease pathophysiology and an early confidence in the mechanism under investigation could help facilitate the selection of not only the most appropriate targets but also the best mechanisms for disease intervention and how to select and optimise the best compounds. Drug target and candidate selection are two of the key decision points within the drug discovery process for which all companies use certain selection criteria to make decisions on which targets to accept into their discovery pipelines and which compounds will pass into development. These steps not only help define the overall productivity of every company but they are also decisions taken without full predictive knowledge of the risks that lie ahead or how best to manage them. In particular, the process of selecting new targets does not normally involve full evaluation of the risk(s) in the mechanism under investigation (the modulation of the target), which may result in an inability to fully connect in,vitro and animal model results to the disease (clinical) setting. The resulting poor progression statistics of many compounds in the clinic is at least partially the result of a lack of understanding of disease pathophysiology. Notably, the lack of efficacy is still a major reason for failure in the clinic.1 Creating a more holistic understanding of disease pathophysiology and an early confidence in the mechanism under investigation could help facilitate the selection of not only the most appropriate targets but also the best mechanisms for disease intervention and how to select and optimise the best compounds. [source] Prediction of glomerular filtration rate in renal transplant recipients: cystatin C or Modification of Diet in Renal Disease equation?CLINICAL TRANSPLANTATION, Issue 2 2006Uwe Pöge Abstract: Background: To overcome disadvantages of serum creatinine two strategies have been suggested to identify patients with reduced glomerular filtration rate (GFR). On the one hand, the Modification of Diet in Renal Disease (MDRD) equation is now recommended to classify the stage of chronic kidney disease. On the other hand, cystatin C (Cys C) has been investigated in numerous studies, finding a higher sensitivity than creatinine in detecting diminished GFR. To date, no comparison of both strategies in patients after renal transplantation has been performed. Methods: One hundred and five consecutive renal transplant recipients underwent 99mTc-DTPA , clearance measurement. Simultaneously, MDRD estimates were calculated and Cys C serum levels were determined. ROC analyses were performed at different decision points from 20 to 70 mL/min/1.73 m2. Results: Although the area under the curve did not differ significantly between MDRD and Cys C within the tested GFR range, the AUC for Cys C tended to be higher when GFR exceeded 55 mL/min/1.73 m2. A significantly higher diagnostic accuracy for Cys C compared with MDRD (p=0.045 at 65 mL/min/1.73 m2) was found when investigating the subgroup of patients with well-functioning grafts (GFR>40 mL/min/1.73 m2). Conclusion: MDRD equation is equivalent to Cys C measurement in renal transplant recipients. As availability of MDRD is superior to Cys C, we recommend GFR estimation using the MDRD equation. Nevertheless, Cys C may serve as a confirmation test of high MDRD estimates in patients with well-functioning grafts because of superior accuracy in these patients. [source] | |||||||||||||