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Decision Rules (decision + rule)

Distribution by Scientific Domains

Medical Sciences	41%
Business, Economics, Finance and Accounting	17%
Humanities and Social Sciences	9%
Mathematics and Statistics	8%
Life Sciences	7%
Information Science and Computing	6%
Earth and Environmental Science	6%
2 Other Domains	6%

Kinds of Decision Rules

clinical decision rule

Selected Abstracts

Independent Evaluation of an Out-of-hospital Termination of Resuscitation (TOR) Clinical Decision Rule

ACADEMIC EMERGENCY MEDICINE, Issue 6 2008
Peter B. Richman MD
Abstract Objectives:, Recently, investigators described a clinical decision rule for termination of resuscitation (TOR) designed to help determine whether to terminate emergency medical services (EMS) resuscitative efforts for out-of-hospital cardiac arrests (OOHCA). The authors sought to evaluate the hypothesis that TOR would predict no survival for patients in an independent cohort of patients with OOHCA. Methods:, This was a retrospective cohort analysis conducted in the state of Arizona. Consecutive, adult, OOHCA were prospectively evaluated from October 2004 through October 2006. A statewide OOHCA database utilizing Utstein-style reporting from 30 different EMS systems was used. Data were abstracted from EMS first care reports and hospital discharge records. The TOR guidelines predict that no survival to hospital discharge will occur if 1) an OOHCA victim does not have return of spontaneous circulation (ROSC), 2) no shocks are administered, and 3) the arrest is not witnessed by EMS personnel. Data were entered into a structured database. Continuous data are presented as means (±standard deviations [SD]) and categorical data as frequency of occurrence, and 95% confidence intervals (CIs) were calculated as appropriate. The primary outcome measure was to determine if any cohort member who met TOR criteria survived to hospital discharge. Results:, There were 2,239 eligible patients; the study group included 2,180 (97.4%) patients for whom the data were complete; mean age was 64 (±11) years, and 35% were female. The majority of patients in the study group met at least one or more of the TOR criteria. A total of 2,047 (93.8%) patients suffered from cardiac arrest that was unwitnessed by EMS; 1,653 (75.8%) had an unwitnessed arrest and no ROSC. With respect to TOR, 1,160 of 2,180 (53.2%) patients met all three criteria; only one (0.09%; 95% CI = 0% to 0.5%) survived to hospital discharge. Conclusions:, The authors evaluated TOR guidelines in an independent, statewide OOHCA database. The results are consistent with the findings of the TOR investigation and suggest that this algorithm is a promising tool for TOR decision-making in the field. [source]

A Decision Rule for Predicting Bacterial Meningitis in Children with Cerebrospinal Fluid Pleocytosis When Gram Stain Is Negative or Unavailable

ACADEMIC EMERGENCY MEDICINE, Issue 5 2008
Bema K. Bonsu MBChB
Abstract Objectives:, Among children with cerebrospinal fluid (CSF) pleocytosis, the task of separating aseptic from bacterial meningitis is hampered when the CSF Gram stain result is unavailable, delayed, or negative. In this study, the authors derive and validate a clinical decision rule for use in this setting. Methods:, This was a review of peripheral blood and CSF test results from 78 children (<19 years) presenting to Children's Hospital Columbus from 1998 to 2002. For those with a CSF leukocyte count of >7/,L, a rule was created for separating bacterial from viral meningitis that was based on routine laboratory tests, but excluded Gram stain. The rule was validated in 158 subjects seen at the same site (Columbus, 2002,2004) and in 871 subjects selected from a separate site (Boston, 1993,1999). Results:, One point each (maximum, 6 points) was assigned for leukocytes >597/,L, neutrophils >74%, glucose <38 mg/dL, and protein >97 mg/dL in CSF and for leukocytes >17,000/mL and bands to neutrophils >11% in peripheral blood. Areas under receiver-operator-characteristic curves (AROCs) for the resultant score were 0.98 for the derivation set and 0.90 and 0.97, respectively, for validation sets from Columbus and Boston. Sensitivity and specificity pairs for the Boston data set were 100 and 44%, respectively, at a score of 0 and 97 and 81% at a score of 1. Likelihood ratios (LRs) increased from 0 at a score of 0 to 40 at a score of ,4. Conclusions:, Among children with CSF pleocytosis, a prediction score based on common tests of CSF and peripheral blood and intended for children with unavailable, negative, or delayed CSF Gram stain results has value for diagnosing bacterial meningitis. [source]

Emergency Medicine Practitioner Knowledge and Use of Decision Rules for the Evaluation of Patients with Suspected Pulmonary Embolism: Variations by Practice Setting and Training Level

ACADEMIC EMERGENCY MEDICINE, Issue 1 2007
Michael S. Runyon MD
Abstract Background Several clinical decision rules (CDRs) have been validated for pretest probability assessment of pulmonary embolism (PE), but the authors are unaware of any data quantifying and characterizing their use in emergency departments. Objectives To characterize clinicians' knowledge of and attitudes toward two commonly used CDRs for PE. Methods By using a modified Delphi approach, the authors developed a two-page paper survey including 15 multiple-choice questions. The questions were designed to determine the respondents' familiarity, frequency of use, and comprehension of the Canadian and Charlotte rules. The survey also queried the frequency of use of unstructured (gestalt) pretest probability assessment and reasons why physicians choose not to use decision rules. The surveys were sent to physicians, physician assistants, and medical students at 32 academic and community hospitals in the United States and the United Kingdom. Results Respondents included 555 clinicians; 443 (80%) work in academic practice, and 112 (20%) are community based. Significantly more academic practitioners (73%) than community practitioners (49%) indicated familiarity with at least one of the two decision rules. Among all respondents familiar with a rule, 50% reported using it in more than half of applicable cases. A significant number of these respondents could not correctly identify a key component of the rule (23% for the Charlotte rule and 43% for the Canadian rule). Fifty-seven percent of all respondents indicated use of gestalt rather than a decision rule in more than half of cases. Conclusions Academic clinicians were more likely to report familiarity with either of these two specific decision rules. Only one half of all clinicians reporting familiarity with the rules use them in more than 50% of applicable cases. Spontaneous recall of the specific elements of the rules was low to moderate. Future work should consider clinical gestalt in the evaluation of patients with possible PE. [source]

Discovering Maximal Generalized Decision Rules Through Horizontal and Vertical Data Reduction

COMPUTATIONAL INTELLIGENCE, Issue 4 2001
Xiaohua Hu
We present a method to learn maximal generalized decision rules from databases by integrating discretization, generalization and rough set feature selection. Our method reduces the data horizontally and vertically. In the first phase, discretization and generalization are integrated and the numeric attributes are discretized into a few intervals. The primitive values of symbolic attributes are replaced by high level concepts and some obvious superfluous or irrelevant symbolic attributes are also eliminated. Horizontal reduction is accomplished by merging identical tuples after the substitution of an attribute value by its higher level value in a pre-defined concept hierarchy for symbolic attributes, or the discretization of continuous (or numeric) attributes. This phase greatly decreases the number of tuples in the database. In the second phase, a novel context-sensitive feature merit measure is used to rank the features, a subset of relevant attributes is chosen based on rough set theory and the merit values of the features. A reduced table is obtained by removing those attributes which are not in the relevant attributes subset and the data set is further reduced vertically without destroying the interdependence relationships between classes and the attributes. Then rough set-based value reduction is further performed on the reduced table and all redundant condition values are dropped. Finally, tuples in the reduced table are transformed into a set of maximal generalized decision rules. The experimental results on UCI data sets and a real market database demonstrate that our method can dramatically reduce the feature space and improve learning accuracy. [source]

Truth and Clinical Decision Rules

ACADEMIC EMERGENCY MEDICINE, Issue 2 2001
David C. Seaberg MD
No abstract is available for this article. [source]

Individual versus Household Migration Decision Rules: Gender and Marital Status Differences in Intentions to Migrate in South Africa

INTERNATIONAL MIGRATION, Issue 1 2009
Bina Gubhaju
This research tests the thesis that the neoclassical microeconomic and the new household economic theoretical assumptions on migration decision-making rules are segmented by gender, marital status, and time frame of intention to migrate. Comparative tests of both theories within the same study design are relatively rare. Utilizing data from the Causes of Migration in South Africa national migration survey, we analyse how individually held "own-future" versus alternative "household well-being" migration decision rules effect the intentions to migrate of male and female adults in South Africa. Results from the gender and marital status specific logistic regressions models show consistent support for the different gender-marital status decision rule thesis. Specifically, the "maximizing one's own future" neoclassical microeconomic theory proposition is more applicable for never married men and women, the "maximizing household income" proposition for married men with short-term migration intentions, and the "reduce household risk" proposition for longer time horizon migration intentions of married men and women. Results provide new evidence on the way household strategies and individual goals jointly affect intentions to move or stay. [source]

Pediatric Emergency Physician Opinions on Ankle Radiograph Clinical Decision Rules

ACADEMIC EMERGENCY MEDICINE, Issue 7 2010
Kathy Boutis MD
ACADEMIC EMERGENCY MEDICINE 2010; 17:709,717 © 2010 by the Society for Academic Emergency Medicine Abstract Objectives:, The Low Risk Ankle Rule (LRAR) is a validated clinical decision rule (CDR) about the indications for ankle radiographs in children with acute blunt ankle trauma. Although application of the LRAR has the potential to safely reduce the rate of ankle radiography by 60%, current x-ray rates in most emergency departments (EDs) in the United States and Canada remain unnecessarily high (85%,100%). To evaluate this gap between knowledge and practice, physicians who treat pediatric ankle injuries in EDs were surveyed to determine physician awareness and use of the LRAR, acceptability of the LRAR as measured by the Ottawa Acceptability for Decision Rules Scale (OADRS), and perceived barriers to the use of a validated pediatric ankle x-ray rule. Methods:, An on-line survey of members of two national pediatric emergency medicine (PEM) physician associations in the United States and Canada was conducted using a modified Dillman technique. Results:, Response rates were 75.6% (149/197) in Canada and 45.7% (352/770) in the United States, yielding an aggregate rate of 51.8%. Only 119 of 478 respondents (24.9%) had heard of the LRAR, and 53 of 432 (12.3%) were sufficiently familiar with the LRAR to apply it. The LRAR scored a mean (± standard deviation [SD]) OADRS score of 4.28 out of 6 (±0.67), comparable to published OADRS scores for two well-known CDRs used in adults. Of the respondents, 434 of 471 (92.1%) at least "slightly agreed" that ankle x-ray CDRs would be useful in their practice, with no significant differences between the two sides of the border (p = 0.28). Ankle x-ray rules were felt to save time by 342 (72.6%) of the participants, and the pediatric ankle exam was considered easy enough to apply a CDR by 306 (65.0%). The most common barriers reported for use of any ankle x-ray rule included perceived reduction in family satisfaction without imaging in 380 (80.7%), nurse-initiated x-ray protocols not based on ankle x-ray rules in 285 (60.5%), concerns about missing a significant fracture in 248 (52.7%), and a preference for own clinical judgment in 246 (52.2%). Conclusions:, Although the LRAR had a high acceptability score among respondents in this survey, this validated CDR is not widely known and is even less frequently applied by PEM physicians in the United States and Canada. Barriers were identified that will guide efforts to improve the knowledge translation of the LRAR into pediatric EDs. [source]

Evaluating Decision Rules for Nitrogen Fertilization

BIOMETRICS, Issue 2 2000
T. Antoniadou
Summary. It is important, both for farmer profit and for the environment, to correctly dose nitrogen fertilizer for crop growth. Fertilizer recommendations are embodied in decision rules, which give a recommended dose of nitrogen (N) as a function of information available at the time the decision is made. In this paper, we first propose a criterion for evaluating decision rules. The proposed criterion is the expectation of the objective function when the decision rule is implemented. The major problem here is the estimation of this criterion. Two estimators are considered, a model-based and a nonparametric estimator. A simulation study shows that, in essentially all cases, the nonparametric estimator is better or no worse than the model-based estimator. The bias in the nonparametric estimator is always very small. [source]

International Survey of Emergency Physicians' Priorities for Clinical Decision Rules

ACADEMIC EMERGENCY MEDICINE, Issue 2 2008
Debra Eagles BSc
Abstract Objectives:, One of the first stages in the development of new clinical decision rules (CDRs) is determination of need. This study examined the clinical priorities of emergency physicians (EPs) working in Australasia, Canada, the United Kingdom, and the United States for the development of future CDRs. Methods:, The authors administered an e-mail and postal survey to members of the national emergency medicine (EM) associations in Australasia, Canada, the United Kingdom, and the United States. Results were analyzed via frequency distributions. Results:, The total response rate was 54.8% (1,150/2,100). The respondents were primarily male (74%), with a mean age of 42.5 years (SD ± 8), and a mean of 12 years of experience (SD ± 7). The top 10 clinical priorities (% selected) were: 1) investigation of febrile child < 36 months (62%); 2) identification of central or serious vertigo (42%); 3) lumbar puncture or admission of febrile child < 3 months (41%); 4) imaging for suspected transient ischemic attack (39%); 5) admission for anterior chest pain (37%); 6) computed tomography (CT) angiography for pulmonary embolus (30%); 7) admission for suicide risk (29%); 8) ultrasound for pain or bleeding in the first trimester of pregnancy (28%); 9) nonspecific weakness in elders (26%); and 10) CT for abdominal pain (25%). Between study countries, there was consistency in identification of clinical problems, but variation in prioritization. Conclusions:, This international survey identified the sampled EPs' priorities for the future development of CDRs. The top priority overall was investigation of the febrile child < 36 months. These results will be valuable to researchers for future development of CDRs in EM that are relevant internationally. [source]

Implementation of Clinical Decision Rules in the Emergency Department

ACADEMIC EMERGENCY MEDICINE, Issue 11 2007
Ian G. Stiell MD
Clinical decision rules (CDRs) are tools designed to help clinicians make bedside diagnostic and therapeutic decisions. The development of a CDR involves three stages: derivation, validation, and implementation. Several criteria need to be considered when designing and evaluating the results of an implementation trial. In this article, the authors review the results of implementation studies evaluating the effect of four CDRs: the Ottawa Ankle Rules, the Ottawa Knee Rule, the Canadian C-Spine Rule, and the Canadian CT Head Rule. Four implementation studies demonstrated that the implementation of CDRs in the emergency department (ED) safely reduced the use of radiography for ankle, knee, and cervical spine injuries. However, a recent trial failed to demonstrate an impact on computed tomography imaging rates. Well-developed and validated CDRs can be successfully implemented into practice, efficiently standardizing ED care. However, further research is needed to identify barriers to implementation in order to achieve improved uptake in the ED. [source]

Toward Improved Implementation of Evidence-based Clinical Algorithms: Clinical Practice Guidelines, Clinical Decision Rules, and Clinical Pathways

ACADEMIC EMERGENCY MEDICINE, Issue 11 2007
Gary M. Gaddis MD
This is a summary of the consensus-building workshop entitled "Guideline Implementation and Clinical Pathways," convened May 15, 2007, at the Academic Emergency Medicine Consensus Conference, "Knowledge Translation in Emergency Medicine: Establishing a Research Agenda and Guide Map for Evidence Uptake." A new term, "evidence-based clinical algorithms" is suggested to encompass evidence-based information codified into clinical pathways, clinical practice guidelines, and clinical decision rules. Examples of poor knowledge translation (KT) relevant to the specialty of emergency medicine are identified, followed by brief descriptions of important research and concepts that inform the research recommendations. Four broad themes for research to improve the KT of evidence-based clinical algorithms are suggested: organizational factors, cognitive factors, social factors, and motivational factors. In all cases, research regarding optimizing KT for the subthemes identified by Glasziou and Haynes, "getting the evidence straight," and "getting the evidence used," are interwoven into the thematic research recommendations. Consensus was reached that the majority of research efforts to evaluate means to improve KT need to be centered on the factors that show promise to enhance "getting the evidence used," focused especially on organizational factors. [source]

Are lobster fisheries being managed effectively?

FISHERIES MANAGEMENT & ECOLOGY, Issue 5 2010
Examples from New Zealand, Nova Scotia
Abstract, Based on performance, management of the New Zealand and Nova Scotia lobster fisheries can be considered successful, but management can be improved by clearer statements of objectives, more efficient mechanics of governance and quicker response to changes in stocks or fisheries. Principal tactics for lobster fishery management are individual transferable quotas and input controls in New Zealand and Nova Scotia respectively. Decision rules were considered important in both approaches and examples are provided of underperforming fisheries in the absence of decision rules. In Nova Scotia, strong fishers' organisations and fishery scientists were effective agents for change, whereas fisher advisory committees operating by consensus were not. In New Zealand, the quota management system provided strong incentives for fishers to become involved in responsible management, to take longer-term views of their resource and to take major management action on their own. [source]

Emergency Medicine Practitioner Knowledge and Use of Decision Rules for the Evaluation of Patients with Suspected Pulmonary Embolism: Variations by Practice Setting and Training Level

THE COMMON EXTERNAL TARIFF IN A CUSTOMS UNION: VOTING, LOGROLLING, AND NATIONAL GOVERNMENT INTERESTS

ECONOMICS & POLITICS, Issue 3 2007
SAMIA COSTA TAVARES
Missing from the analysis of customs unions has been a consideration of collective decision-making by countries regarding the union's common trade policy. In the case of the common European external tariff, how governments voted was not public information. This paper uses a unique dataset to derive member states' tariff preferences, which are then used to establish the decision rule before 1987, when individual governments had veto power. Results indicate a principle of unanimity, as well as the presence of logrolling. The political equilibrium for the common external tariff is also illustrated to have shifted as a result of union enlargements. [source]

How feather colour reflects its carotenoid content

FUNCTIONAL ECOLOGY, Issue 4 2003
Lauri Saks
Summary 1Many birds sequester carotenoid pigments in colourful patches of feathers to advertise or compete for mates. Because carotenoids can be scarce in nature and serve valuable physiological functions, only the highest-quality individuals are thought to acquire or allocate more pigments for use in sexual displays. 2A critical but rarely tested assumption of carotenoid-based signals is that the colour of pigmented feather patches directly reveals the total amount of carotenoids contained within them. 3We studied the relationship between carotenoid-based coloration (hue, chroma and brightness) and the pigment content of tail feathers in wild-caught and captive male greenfinches (Carduelis chloris[Linnaeus]). Greenfinches incorporate two main carotenoids , canary xanthophylls A and B , into feathers to develop yellow patches of colour in their tail. 4Variation in feather carotenoid content explained 32,51% of variation in chroma and hue of the yellow parts of tail feathers, while feather brightness was not significantly related to carotenoid concentration. Hence, chroma and hue appear good candidates to indicate feather carotenoid content. 5Birds with the most colourful feathers deposited significantly more of both canary xanthophylls into plumage. Thus, there does not appear to be a specific biochemical strategy for becoming colourful in greenfinches; males instead follow the general decision rule to deposit as many xanthophylls as possible into feathers to become yellow. [source]

Searching for certainty in an uncertain world: the difficulty of giving up the experiential for the rational mode of thinking

JOURNAL OF BEHAVIORAL DECISION MAKING, Issue 2 2003
Yaacov Schul
Abstract Our research explores predictions that people make in a simple environment consisting of sequences of a binary signal followed by two possible outcomes. In order to optimize their prediction success, respondents should use a very simple decision rule, called maximization, whereby they consistently predict according to the signal. In line with past research, our findings show that even respondents who realized after the experiment that maximization is optimal failed to use it during the experiment itself. We discuss conditions that weaken or reinforce behaving according to the optimal rule in a repeated choice situation. Experiment 1 shows that individuals who are forced to plan their strategy and justify their actions are more likely to discover and use the optimal rule than those not forced to do so. Thinking about the appropriateness of one's performance can be done in two different orientations: focusing on the past (justifying past actions) or on the future (planning future action). Experiment 2 shows that planning induces rule-base thinking, while justifying fails to do so. These findings are discussed within a theoretical framework which suggest an interplay between the experiential and the rational modes of processing. Copyright © 2003 John Wiley & Sons, Ltd. [source]

Routine chest X-ray is not required after a low-risk central venous cannulation

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2009
A. PIKWER
Background: Knowledge of the radiographic catheter tip position after central venous cannulation is normally not required for short-term catheter use. Detection of a possible iatrogenic pneumothorax may nevertheless justify routine post-procedure chest X-ray. Our aim was to design a clinical decision rule to select patients for radiographic evaluation after central venous cannulation. Methods: A total of 2230 catheterizations performed using external jugular, internal jugular or subclavian venous approaches during a 4-year period were included consecutively. Information on patient data and corresponding procedures was recorded prospectively. A post-procedure chest X-ray was obtained after each cannulation. Results: Thirteen cases (0.58%) of cannulation-associated pneumothorax were identified. The risk of pneumothorax after a technically difficult (1.8%) or subclavian (1.6%) cannulation was significantly higher than after cannulation not considered as difficult (0.37%) or performed using other routes (0.33%). Clinical signs of pneumothorax within 8 h of cannulation were found in all seven patients with pneumothorax requiring specific treatment. A new clinical decision rule for radiographic evaluation after central venous cannulation based on the results of the present study shows that 48% of the post-procedure chest X-rays performed in our patients were clinically redundant. Conclusion: Clinical symptoms were reported in all patients with pneumothorax requiring specific treatment. Approximately half of the post-procedure chest X-ray controls could be avoided using the proposed clinical decision rule to select patients for radiographic evaluation after central venous cannulation. A large prospective multi-centre study should be carried out to further evaluate this decision rule. [source]

Prospective Evaluation of Real-time Use of the Pulmonary Embolism Rule-out Criteria in an Academic Emergency Department

ACADEMIC EMERGENCY MEDICINE, Issue 9 2010
Jeffrey A. Kline MD
Abstract Objectives:, The pulmonary embolism rule-out criteria (PERC rule) is a nine-component decision rule derived to exclude pulmonary embolism (PE) without the use of formal diagnostic testing (D-dimer, computed tomography pulmonary angiography, ventilation,perfusion lung scanning, or venous ultrasonography) when all nine components are negative ("PERC negative"). This study examined whether clinicians who document PERC negative also document results of all nine components of the PERC rule. Methods:, This was a pilot study at a single-center, urban teaching emergency department (ED) with a residency program in emergency medicine. Patients were over 17 years of age with at least one of nine predefined chief complaints. Clinicians were asked three questions regarding suspicion for PE, intent to use the PERC rule, and the result. Charts were independently reviewed by two authors for fidelity of the nine PERC components. Patients were followed for PE outcome at 14 days. Results:, The study examined 526 patients cared for by 82 clinicians, who indicated suspicion for PE in 183 of 526 (35%) and intent to use the PERC rule in 115 of 526 (22%) cases, of whom 65 of 115 were documented as PERC negative. No formal test for PE was ordered in 49 of 65 (75%), and 46 of 49 had incomplete documentation to support PERC negative. The most common deficiency was omission of two risk factors for PE in the rule (prior venous thromboembolism or recent surgery). Six patients had PE diagnosed within 14 days, but none of these had been deemed PERC negative. Conclusions:, Clinicians seldom document all nine data elements of the PERC rule in patients they deem PERC negative. These data suggest the need for paper or electronic aids to support use of the PERC rule. ACADEMIC EMERGENCY MEDICINE 2010; 17:1016,1019 © 2010 by the Society for Academic Emergency Medicine [source]

High D-dimer levels increase the likelihood of pulmonary embolism

JOURNAL OF INTERNAL MEDICINE, Issue 2 2008
L. W. Tick
Abstract. Objective., To determine the utility of high quantitative D-dimer levels in the diagnosis of pulmonary embolism. Methods., D-dimer testing was performed in consecutive patients with suspected pulmonary embolism. We included patients with suspected pulmonary embolism with a high risk for venous thromboembolism, i.e. hospitalized patients, patients older than 80 years, with malignancy or previous surgery. Presence of pulmonary embolism was based on a diagnostic management strategy using a clinical decision rule (CDR), D-dimer testing and computed tomography. Results., A total of 1515 patients were included with an overall pulmonary embolism prevalence of 21%. The pulmonary embolism prevalence was strongly associated with the height of the D-dimer level, and increased fourfold with D-dimer levels greater than 4000 ng mL,1 compared to levels between 500 and 1000 ng mL,1. Patients with D-dimer levels higher than 2000 ng mL,1 and an unlikely CDR had a pulmonary embolism prevalence of 36%. This prevalence is comparable to the pulmonary embolism likely CDR group. When D-dimer levels were above 4000 ng mL,1, the observed pulmonary embolism prevalence was very high, independent of CDR score. Conclusion., Strongly elevated D-dimer levels substantially increase the likelihood of pulmonary embolism. Whether this should translate into more intensive diagnostic and therapeutic measures in patients with high D-dimer levels irrespective of CDR remains to be studied. [source]

Use of decision rules for osteoporosis prevention and treatment: Implications for nurse practitioners

JOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 6 2007
Michael Anders PhD, RRT (Associate Professor)
Abstract Purpose: To describe the current literature regarding the benefits of bone mineral density (BMD) screening and to discuss clinical decision rules for BMD screening. Data sources: Extensive review of the scientific literature regarding osteoporosis, BMD screening, and current clinical decision rules. Conclusions: Osteoporosis is a disease characterized by deterioration of bone and increased susceptibility to fractures, crippling, and disfigurement. BMD testing is the best predictor for osteoporosis and associated fractures; however, routine global BMD testing is cost-prohibitive. A need exists for a selective and practical clinical decision rule for referral for testing. Implications for practice: Several effective clinical decision rules are presented, and their uses and applications are described. The osteoporosis self-assessment tool is recommended by the authors because of its predictive power and ease of use. [source]

A Bayesian discovery procedure

JOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES B (STATISTICAL METHODOLOGY), Issue 5 2009
Michele Guindani
Summary., We discuss a Bayesian discovery procedure for multiple-comparison problems. We show that, under a coherent decision theoretic framework, a loss function combining true positive and false positive counts leads to a decision rule that is based on a threshold of the posterior probability of the alternative. Under a semiparametric model for the data, we show that the Bayes rule can be approximated by the optimal discovery procedure, which was recently introduced by Storey. Improving the approximation leads us to a Bayesian discovery procedure, which exploits the multiple shrinkage in clusters that are implied by the assumed non-parametric model. We compare the Bayesian discovery procedure and the optimal discovery procedure estimates in a simple simulation study and in an assessment of differential gene expression based on microarray data from tumour samples. We extend the setting of the optimal discovery procedure by discussing modifications of the loss function that lead to different single-thresholding statistics. Finally, we provide an application of the previous arguments to dependent (spatial) data. [source]

Management studies using a combination of D-dimer test result and clinical probability to rule out venous thromboembolism: a systematic review

JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 11 2005
A. J. TEN CATE-HOEK
Summary.,Background:,While the number of patients with suspected venous thromboembolism (VTE) referred to hospital emergency units increases, the proportion in whom the diagnosis can be confirmed is decreasing. A more efficient but safe diagnostic strategy is needed. Objective:,To evaluate the safety of withholding anticoagulant therapy in patients suspected of VTE based on a diagnostic work-up that combines a clinical decision rule (CDR) with a D-dimer test result without performing additional diagnostic tests. Patients/methods:,We searched Medline (January 1996,December 2004)-related articles and reference lists of studies in English for prospective clinical studies that managed consecutive patients suspected of VTE and used a D-dimer assay combined with an explicit CDR or implicit clinical judgment. Results:,We identified 11 studies in which 6837 consecutive outpatients suspected of VTE were included. In the combined management studies, the overall rate of thromboembolic events was nine out of 2056 patients (0.44 %, 95% CI 0.2%,0.83%) in whom anticoagulants were withheld based on the D-dimer result and a low clinical score. Similar results were obtained with qualitative and quantitative D-dimer tests and with different decision rules. The rate of exclusion varied between 30% and 50% and was highest with a low incidence of VTE among those referred. Conclusion:,Withholding anticoagulant treatment in patients suspected of VTE on the basis of a work-up consisting of a low clinical probability combined with either a qualitative or quantitative D-dimer test result is safe. [source]

Soft Tissue Infections and Emergency Department Disposition: Predicting the Need for Inpatient Admission

ACADEMIC EMERGENCY MEDICINE, Issue 12 2009
Alfredo Sabbaj MD
Abstract Objectives:, Little empiric evidence exists to guide emergency department (ED) disposition of patients presenting with soft tissue infections. This study's objective was to generate a clinical decision rule to predict the need for greater than 24-hour hospital admission for patients presenting to the ED with soft tissue infection. Methods:, This was a retrospective cohort study of consecutive patients presenting to a tertiary care hospital ED with diagnosis of nonfacial soft tissue infection. Standardized chart review was used to collect 29 clinical variables. The primary outcome was >24-hour hospital admission (either general admission or ED observation unit), regardless of initial disposition. Patients initially discharged home and later admitted for more than 24 hours were included in the outcome. Data were analyzed using classification and regression tree (CART) analysis and multivariable logistic regression. Results:, A total of 846 patients presented to the ED with nonfacial soft tissue infection. After merging duplicate records, 674 patients remained, of which 81 (12%) required longer than 24-hour admission. Using CART, the strongest predictors of >24-hour admission were patient temperature at ED presentation and mechanism of infection. In the multivariable logistic regression model, initial patient temperature (odds ratio [OR] for each degree over 37°C = 2.91, 95% confidence interval [CI] = 1.65 to 5.12) and history of fever (OR = 3.02, 95% CI = 1.41 to 6.43) remained the strongest predictors of hospital admission. Despite these findings, there was no combination of factors that reliably identified more than 90% of target patients. Conclusions:, Although we were unable to generate a high-sensitivity decision rule to identify ED patients with soft tissue infection requiring >24-hour admission, the presence of a fever (either by initial ED vital signs or by history) was the strongest predictor of need for >24-hour hospital stay. These findings may help guide disposition of patients presenting to the ED with nonfacial soft tissue infections. [source]

Is Rule by Majorities Special?

POLITICAL STUDIES, Issue 1 2010
Hugh Ward
One way of making decisions is for political associates or their representatives to vote on each issue separately in accordance with the majority principle and then take the cumulative outcomes of such majority decision making to define the collective choice for public policy. We call such a system one of majorities rule. Thought of in spatial terms, majorities rule is equivalent to the principle of making decisions according to the issue-by-issue median of voter preferences. If popular control and political equality are core democratic values, they can be rendered as requirements on a collective choice rule, involving resoluteness, anonymity, strategy-proofness and responsiveness. These requirements entail that the collective decision rule be a percentile method. If we then add a requirement of impartiality, as exhibited in a collective choice rule which would be chosen behind a veil of ignorance, then the issue-by-issue median is uniquely identified as a fair rule. Hence, majorities rule is special. Some objections to this line of reasoning are considered. [source]

Seasonal unit root tests and the role of initial conditions

THE ECONOMETRICS JOURNAL, Issue 3 2008
David I. Harvey
Summary, In the context of regression-based (quarterly) seasonal unit root tests, we examine the impact of initial conditions (one for each quarter) of the process on test power. We investigate the behaviour of the well-known OLS detrended HEGY seasonal unit root tests together with their quasi-differenced (QD) detrended analogues, when the initial conditions are not asymptotically negligible. We show that the asymptotic local power of a test at a given frequency depends on the value of particular linear (frequency specific) combinations of the initial conditions. Consistent with previous findings in the nonseasonal case, the QD detrended test at a given spectral frequency dominates on power for relatively small values of this combination, while the OLS detrended test dominates for larger values. Since, in practice, the seasonal initial conditions are not observed, in order to maintain good power across both small and large initial conditions, we develop tests based on a union of rejections decision rule; rejecting the unit root null at a given frequency (or group of frequencies) if either of the relevant QD and OLS detrended HEGY tests rejects. This procedure is shown to perform well in practice, simultaneously exploiting the superior power of the QD (OLS) detrended HEGY test for small (large) combinations of the initial conditions. Moreover, our procedure is particularly adept in the seasonal context since, by design, it exploits the power advantage of the QD (OLS) detrended HEGY tests at a particular frequency when the relevant initial condition is small (large) without imposing that same method of detrending on tests at other frequencies. [source]

Multicenter Validation of the Philadelphia EMS Admission Rule (PEAR) to Predict Hospital Admission in Adult Patients Using Out-of-hospital Data

ACADEMIC EMERGENCY MEDICINE, Issue 6 2009
Zachary F. Meisel MD
Abstract Objectives:, The objective was to validate a previously derived prediction rule for hospital admission using routinely collected out-of-hospital information. Methods:, The authors performed a multicenter retrospective cohort study of 1,500 randomly selected, adult patients transported to six separate emergency departments (EDs; three community and three academic hospitals in three separate health systems) by a city-run emergency medical services (EMS) system over a 1-year period. Patients younger than 18 years or who bypassed the ED to be evaluated by trauma, obstetric, or psychiatric teams were excluded. The score consisted of six weighted elements that generated a total score (0,14): age , 60 years (3 points); chest pain (3); shortness of breath (3); dizzy, weakness, or syncope (2); history of cancer (2); and history of diabetes (1). Receiver operator characteristic (ROC) curves for the decision rule and admission rates were calculated among individual hospitals and for the entire cohort. Results:, A total of 1,102 patients met inclusion criteria. The admission rate for the entire cohort was 40%, and individual hospital admission rates ranged from 28% to 57%. Overall, 34% had a score of ,4, and 29% had a score of ,5. Area under the ROC curve (AUC) for the combined cohort was 0.83 for all admissions and 0.72 for intensive care unit (ICU) admissions; AUCs at individual hospitals ranged from 0.72 to 0.85. The admission rate for a score of ,4 was 77%; for a score of ,5 the admission rate was 80%. Conclusions:, The ability of this EMS rule to predict the likelihood of hospital admission appears valid in this multicenter cohort. Further studies are needed to measure the impact and feasibility of using this rule to guide decision-making. [source]

Pediatric Emergency Physician Opinions on Ankle Radiograph Clinical Decision Rules

International Survey of Emergency Physicians' Awareness and Use of the Canadian Cervical-Spine Rule and the Canadian Computed Tomography Head Rule

ACADEMIC EMERGENCY MEDICINE, Issue 12 2008
Debra Eagles MD
Abstract Objectives:, The derivation and validation studies for the Canadian Cervical-Spine (C-Spine) Rule (CCR) and the Canadian Computed Tomography (CT) Head Rule (CCHR) have been published in major medical journals. The objectives were to determine: 1) physician awareness and use of these rules in Australasia, Canada, the United Kingdom, and the United States and 2) physician characteristics associated with awareness and use. Methods:, A self-administered e-mail and postal survey was sent to members of four national emergency physician (EP) associations using a modified Dillman technique. Results were analyzed using repeated-measures logistic regression models. Results:, The response rate was 54.8% (1,150/2,100). Reported awareness of the CCR ranged from 97% (Canada) to 65% (United States); for the CCHR it ranged from 86% (Canada) to 31% (United States). Reported use of the CCR ranged from 73% (Canada) to 30% (United States); for the CCHR, it was 57% (Canada) to 12% (United States). Predictors of awareness were country, type of rule, full-time employment, younger age, and teaching hospital (p < 0.05). Significant differences in use of the CCR by country were observed, but not for the CCHR. Teaching hospitals were more likely to use the CCR than nonteaching hospitals, but less likely to use the CCHR. Conclusions:, This large international study found notable differences among countries with regard to knowledge and use of the CCR and CCHR. Awareness and use of both rules were highest in Canada and lowest in the United States. While younger physicians, those employed full-time, and those working in teaching hospitals were more likely to be aware of a decision rule, age and employment status were not significant predictors of use. A better understanding of factors related to awareness and use of emergency medicine (EM) decision rules will enhance our understanding of knowledge translation and facilitate strategies to enhance dissemination and implementation of future rules. [source]