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101.
Eldon Spackman Mark Sculpher Jo Howard Moira Malfroy Charlotte Llewelyn Louise Choo Renate Hodge Tony Johnson David C. Rees Karin Fijnvandraat Melanie Kirby‐Allen Sally Davies Lorna Williamson 《European journal of haematology》2014,92(3):249-255
The study's objective was to assess the cost‐effectiveness of preoperative transfusion compared with no preoperative transfusion in patients with sickle cell disease undergoing low‐ or medium‐risk surgery. Seventy patients with sickle cell disease (HbSS/Sß0thal genotypes) undergoing elective surgery participated in a multicentre randomised trial, Transfusion Alternatives Preoperatively in Sickle Cell Disease (TAPS). Here, a cost‐effectiveness analysis based on evidence from that trial is presented. A decision‐analytic model is used to incorporate long‐term consequences of transfusions and acute chest syndrome. Costs and health benefits, expressed as quality‐adjusted life years (QALYs), are reported from the ‘within‐trial’ analysis and for the decision‐analytic model. The probability of cost‐effectiveness for each form of management is calculated taking into account the small sample size and other sources of uncertainty. In the range of scenarios considered in the analysis, preoperative transfusion was more effective, with the mean improvement in QALYs ranging from 0.018 to 0.206 per patient, and also less costly in all but one scenario, with the mean cost difference ranging from ?£813 to £26. All scenarios suggested preoperative transfusion had a probability of cost‐effectiveness >0.79 at a cost‐effectiveness threshold of £20 000 per QALY. 相似文献
102.
Brenda Robles Tony Kuo Michael Leighs May Choo Wang Paul Simon 《American journal of public health》2014,104(7):e14-e19
Recent federal initiatives have used estimates of population reach as a proxy metric for intervention impact, in part to inform resource allocation and programmatic decisions about competing priorities in the community. However, in spite of its utility, population reach as a singular metric of intervention impact may be insufficient for guiding multifaceted program decisions. A more comprehensive, validated approach to measure or forecast dose may complement reach estimates to inform decision makers about optimal ways to use limited resources.Although federal initiatives in obesity prevention have typically recommended the use of evidence-based community strategies,1 less is known about the level of impact that these strategies can contribute to improving health in the real world. The absence of this type of practice-based information often poses significant challenges to funding agencies and program planners that are tasked with prioritizing and selecting intervention strategies for a city or community. Given that this information is not readily available or regularly reported, recent federal initiatives have begun to request data on intervention impact, using estimates of population reach as a proxy metric for predicting the extent of intervention effectiveness. The Centers for Disease Control and Prevention, for example, recently provided guidance on how to measure and report reach for a range of obesity prevention interventions focused on improving systems and environments in cities and communities across the United States.2 They broadly defined “reach” as the number of unique individuals affected by a program initiative and further refined this concept to include direct reach as the number of unique individuals exposed to the intervention in some way and indirect reach as the number of unique individuals indirectly exposed to the intervention in some way but who are not residents of a targeted community (e.g., visitors).2 To provide more specificity, other agencies and organizations (e.g., the Center for Community Health and Evaluation) have sought to account for the effects of community health interventions by incorporating intervention dose as an additional parameter for consideration in their priority-setting process and program planning.3 In this context, “dose” has been defined as the product of reach (percentage of people exposed to an intervention) and strength (the degree to which people reached by the intervention changed their health behaviors).3 Although dose is a more robust measure of intervention impact, reach is generally easier to estimate and use, given the time constraints and limited availability of relevant data sources to local leaders who must make daily decisions about policy development, program implementation, and operations. It is important to note, however, that the Centers for Disease Control and Prevention and the Center for Community Health and Evaluation differ in their definitions of “reach.” Although the former’s definition distinguishes between direct and indirect number of unique individuals, the latter’s does not, making comparisons of this metric across studies, interventions, places, settings, and times difficult to achieve.Although the aforementioned metrics (reach and dose) can provide meaningful data to inform health and public health decisions,4,5 few strategic planning efforts have incorporated their use in the prioritization process.6 In this article, we describe the effort of the Los Angeles County Department of Public Health (DPH) to systematically incorporate population reach as a proxy metric of intervention impact, using it to guide prioritization of system and environmental change strategies for community implementation (when appropriate). The motivation for writing this article is to inform the efforts of other agencies similarly tasked with addressing the obesity epidemic in their communities but often constrained by limited resources and several competing priorities in their jurisdictions. 相似文献
103.
Michael F. T. Koehler Philippe Bergeron Edna F. Choo Kevin Lau Chudi Ndubaku Danette Dudley Paul Gibbons Brad E. Sleebs Carl S. Rye George Nikolakopoulos Chinh Bui Sanji Kulasegaram Wilhelmus J. A. Kersten BrianJ. Smith Peter E. Czabotar Peter M. Colman DavidC. S. Huang Jonathan B. Baell Keith G. Watson Lisa Hasvold Zhi-Fu Tao Le Wang AndrewJ. Souers Steven W. Elmore John A. Flygare Wayne J. Fairbrother Guillaume Lessene 《ACS medicinal chemistry letters》2014,5(6):662-667
104.
Muthu Rama Krishnan Mookiah U. Rajendra Acharya Joel E.W. Koh Chua Kuang Chua Jen Hong Tan Vinod Chandran Choo Min Lim Kevin Noronha Augustinus Laude Louis Tong 《Medical & biological engineering & computing》2014,52(9):781-796
Age-related macular degeneration (AMD) affects the central vision and subsequently may lead to visual loss in people over 60 years of age. There is no permanent cure for AMD, but early detection and successive treatment may improve the visual acuity. AMD is mainly classified into dry and wet type; however, dry AMD is more common in aging population. AMD is characterized by drusen, yellow pigmentation, and neovascularization. These lesions are examined through visual inspection of retinal fundus images by ophthalmologists. It is laborious, time-consuming, and resource-intensive. Hence, in this study, we have proposed an automated AMD detection system using discrete wavelet transform (DWT) and feature ranking strategies. The first four-order statistical moments (mean, variance, skewness, and kurtosis), energy, entropy, and Gini index-based features are extracted from DWT coefficients. We have used five (t test, Kullback–Lieber Divergence (KLD), Chernoff Bound and Bhattacharyya Distance, receiver operating characteristics curve-based, and Wilcoxon) feature ranking strategies to identify optimal feature set. A set of supervised classifiers namely support vector machine (SVM), decision tree, \(k\) -nearest neighbor ( \(k\) -NN), Naive Bayes, and probabilistic neural network were used to evaluate the highest performance measure using minimum number of features in classifying normal and dry AMD classes. The proposed framework obtained an average accuracy of 93.70 %, sensitivity of 91.11 %, and specificity of 96.30 % using KLD ranking and SVM classifier. We have also formulated an AMD Risk Index using selected features to classify the normal and dry AMD classes using one number. The proposed system can be used to assist the clinicians and also for mass AMD screening programs. 相似文献
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108.
Hau Wei Khoo Terrence Chi Hong Hui Salahudeen Mohamed Haja Mohideen Yeong Shyan Lee Charlene Jin Yee Liew Shawn Shi Xian Kok Barnaby Edward Young Sean Wei Xiang Ong Shirin Kalimuddin Seow Yen Tan Jiashen Loh Lai Peng Chan Angeline Choo Choo Poh Steven Bak Siew Wong Yee-Sin Leo David Chien Lye Gregory Jon Leng Kaw Cher Heng Tan 《Singapore medical journal》2021,62(9):458
INTRODUCTIONChest radiographs (CXRs) are widely used for the screening and management of COVID-19. This article describes the radiographic features of COVID-19 based on an initial national cohort of patients.METHODSThis is a retrospective review of swab-positive patients with COVID-19 who were admitted to four different hospitals in Singapore between 22 January and 9 March 2020. Initial and follow-up CXRs were reviewed by three experienced radiologists to identify the predominant pattern and distribution of lung parenchymal abnormalities.RESULTSIn total, 347 CXRs of 96 patients were reviewed. Initial CXRs were abnormal in 41 (42.7%) out of 96 patients. The mean time from onset of symptoms to CXR abnormality was 5.3 ± 4.7 days. The predominant pattern of lung abnormality was ground-glass opacity on initial CXRs (51.2%) and consolidation on follow-up CXRs (51.0%). Multifocal bilateral abnormalities in mixed central and peripheral distribution were observed in 63.4% and 59.2% of abnormal initial and follow-up CXRs, respectively. The lower zones were involved in 90.2% of initial CXRs and 93.9% of follow-up CXRs.CONCLUSIONIn a cohort of swab-positive patients, including those identified from contact tracing, we found a lower incidence of CXR abnormalities than was previously reported. The most common pattern was ground-glass opacity or consolidation, but mixed central and peripheral involvement was more common than peripheral involvement alone. 相似文献
109.
Zachary H Pugh Sanghyun Choo Joseph C Leshin Kristen A Lindquist Chang S Nam 《Social cognitive and affective neuroscience》2022,17(2):206
Situated models of emotion hypothesize that emotions are optimized for the context at hand, but most neuroimaging approaches ignore context. For the first time, we applied Granger causality (GC) analysis to determine how an emotion is affected by a person’s cultural background and situation. Electroencephalographic recordings were obtained from mainland Chinese (CHN) and US participants as they viewed and rated fearful and neutral images displaying either social or non-social contexts. Independent component analysis and GC analysis were applied to determine the epoch of peak effect for each condition and to identify sources and sinks among brain regions of interest. We found that source–sink couplings differed across culture, situation and culture × situation. Mainland CHN participants alone showed preference for an early-onset source–sink pairing with the supramarginal gyrus as a causal source, suggesting that, relative to US participants, CHN participants more strongly prioritized a scene’s social aspects in their response to fearful scenes. Our findings suggest that the neural representation of fear indeed varies according to both culture and situation and their interaction in ways that are consistent with norms instilled by cultural background. 相似文献
110.
Chao-Hsiun Tang Shih-Pei Shen Min-Wei Huang Hong Qiu Sayuri Watanabe Choo Hua Goh Yanfang Liu 《European psychiatry》2022,65(1)
BackgroundLong-acting injectable (LAI) antipsychotics improve medication adherence in patients with schizophrenia and extend the duration of therapeutic drug levels but with administration of an increased dose. Real-world mortality data in patients prescribed LAIs are lacking. We conducted a population-based cohort study to estimate and compare the incidence rates of all-cause death and completed suicide in patients with schizophrenia/schizoaffective disorder exposed to LAIs and oral antipsychotics.MethodsPatients with a diagnosis of schizophrenia/schizoaffective disorder between January 1, 2015 and November 30, 2019 were enrolled from the Taiwan National Health Insurance Research Database and linked to Death Registry records. Eligible patients were new antipsychotic users. Relative risks of death for each antipsychotic compared with oral paliperidone were evaluated using a Cox proportional hazard model adjusted for age, sex, Charlson Comorbidity Index, index year, bipolar or major depressive or other mood disorders, mental disorders due to drug use, and baseline hospitalization frequency.ResultsThere were 228,791.08 person-years of follow-up (mean 2.48 years). The incidence rates of all-cause death in users of LAI paliperidone administered monthly (PP1M) and every 3 months (PP3M) were 7.40/1,000 person-years (95% confidence interval 5.94–9.11) and 9.93 (5.88–15.79), respectively. The incidences of completed suicide were 2.03/1,000 person-years (1.32–2.99) and 3.10 (1.14–6.88), respectively. No significant associations were observed between PP1M and PP3M compared to oral paliperidone in incidences of all-cause death or for completed suicide.DiscussionNo increased risk of all-cause death or completed suicide was observed in users of antipsychotic LAIs, including PP1M and PP3M. 相似文献