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Orna Reges,1,2,* Hagay Weinberg,3,4,* Moshe Hoshen,1,5 Philip Greenland,2 Hana’a Rayyan-Assi,1 Meytal Avgil Tsadok,1 Asaf Bachrach,1 Ran Balicer,1,6 Morton Leibowitz,1 Moti Haim7,8 1Clalit Research Institute, Clalit Health Services, Tel Aviv, Israel; 2Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; 3Internal Medicine Department, Meir Medical Center, Kfar-Saba, Israel; 4Department of Medicine, MidCentral District Health Board, Palmerston-North, New Zealand; 5National Information Systems, Computational Authority, Ministry of Health, Jerusalem, Isarel; 6Department of Epidemiology, Ben-Gurion University of the Negev, Beer-Sheva, Israel; 7Department of Cardiology, Soroka University Medical Center, Beer Sheva, Israel; 8Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel*These authors contributed equally to this workCorrespondence: Orna RegesDepartment of Preventive Medicine, Northwestern University Feinberg School of Medicine, 680 North Lake Shore Drive, Suite 1400, Chicago, IL 60611, USAEmail orna.reges@gmail.comPurpose: Previous studies have demonstrated differences in atrial fibrillation (AF) detection based on data from hospital sources without data from outpatient sources. We investigated the detection of documented diagnoses of non-valvular AF in a large Israeli health-care organization using electronic health record data from multiple sources.Patients and Methods: This was an open-chart validation study. Three distinct algorithms for identifying AF in electronic health records, differing in the source of their International Classification of Diseases, Ninth Revision code and use of the associated free text, were defined. Algorithm 1 incorporated inpatient data with outpatient data and the associated free text. Algorithm 2 incorporated inpatient and outpatient data regardless of the free text associated with AF diagnosis. Algorithm 3 used only inpatient data source. These algorithms were compared to a gold standard and their sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. To establish the gold standard (documentation of arrhythmia based on electrocardiography interpretation or a cardiologist’s written diagnosis), 200 patients at highest risk for having non-valvular AF were randomly selected for open-chart validation by two physicians.Results: The algorithm that included hospital settings, outpatient settings, and incorporated associated free text in the outpatient records had the optimal balance between all validation measures, with a high level of sensitivity (85.4%), specificity (95.0%), PPV (81.4%), and NPV (96.2%). The alternative algorithm that combined inpatient and outpatient data without free text also performed better than the algorithm that included only hospital data (82.9%, 95.0%, 81.0%, and 95.6%, compared to 70.7%, 96.9%, 85.3%, and 92.8%, sensitivity, specificity, PPV, and NPV, respectively).Conclusion: In this study, involving a comprehensive data collection from inpatient and outpatient sources, incorporating outpatient data with inpatient data improved the diagnosis of non-valvular AF compared to inpatient data alone.Keywords: atrial fibrillation, validation, electronic health records

Abstract Background The development and propagation of malaria parasites in their vertebrate host is a complex process in which various host and parasite factors are involved. Sometimes the evolution of parasitaemia seems to be quelled by parasite load. In order to understand the typical dynamics of evolution of parasitaemia, various mathematical models have been developed. The basic premise ingrained in most models is that the availability of uninfected red blood cells (RBC) in which the parasite develops is a limiting factor in the propagation of the parasite population. Presentation of the hypothesis We would like to propose that except in extreme cases of severe malaria, there is no limitation in the supply of uninfected RBC for the increase of parasite population. Testing the hypothesis In this analysis we examine the biological attributes of the parasite-infected RBC such as cytoadherence and rosette formation, and the rheological properties of infected RBC, and evaluate their effects on blood flow and clogging of capillaries. We argue that there should be no restriction in the availability of uninfected RBC in patients. Implication of the hypothesis There is no justification for the insertion of RBC supply as a factor in mathematical models that describe the evolution of parasitaemia in the infected host. Indeed, more recent models, that have not inserted this factor, successfully describe the evolution of parasitaemia in the infected host.

Documentation of primary care teams' involvement in disparity reduction efforts exists, yet little is known about how teams interact or perceive their effectiveness. We investigated how the social network and structural ties among primary-care-clinic team members relate to their perceived team effectiveness (TE), in a large-scale disparity reduction intervention in Israel's largest insurer and provider of services. A mixed-method design of Social Network Analysis and qualitative data collection was employed. 108 interviews with medical, nursing, and administrative teams of 26 clinics and their respective managerial units were performed and information on the organizational ties, analyzing density and centrality, collected. Pearson correlations examined association between network measures and perceived TE. Clinics with strong intra-clinic density and high clinic–subregional-management density were positively correlated with perceived TE. Clinic in-degree centrality was also positively associated with perceived TE. Qualitative analyses support these findings with teamwork emerging as a factor which can impede or facilitate teams' ability to design and implement disparity reduction interventions. The study demonstrates that in an organization-wide disparity reduction initiative, cohesive intra-network structure and close relations with mid-level management increase the likelihood that teams perceive themselves as possessing the skills and resources needed to lead and implement disparity reduction efforts. List of abbreviations Team Effectiveness (TE); Clalit Health Services (Clalit); Social Network Analysis (SNA); Quality Improvement (QI); National Health Care Collaborative (NHPC); Tampa Bay Community Cancer Network (TBCCN) [ABSTRACT FROM AUTHOR]

Background: To support malaria control strategies, prior knowledge of disease risk is necessary. Developing a model to explain the transmission of malaria, in endemic and epidemic regions, is of high priority in developing health system interventions. We develop, fit and validate a non-spatial dynamic model driven by meteorological conditions that can capture seasonal malaria transmission dynamics at the village level in a malaria holoendemic area of north-western Burkina Faso. Methods: A total of 676 children aged 6-59 months took part in this study. Trained interviewers visited children at home weekly from December 2003 to November 2004 for Plasmodium falciparum malaria infection detection. Anopheles daily biting rate, mortality rate and growth rate were evaluated. Digital meteorological stations measured ambient temperature, humidity and rainfall in each site. Results: The overall P. falciparum malaria infection incidence was 1.1 episodes per person year. There was strong seasonal variation in P. falciparum malaria infection incidence with a peak observed in August and September, corresponding to the rainy season and a high number of mosquitoes. The model estimates of monthly mosquito abundance and the incidence of malaria infection correlated well with observed values. The fit was sensitive to daily mosquito survival and daily human parasite clearance. Conclusion: The model has demonstrated potential for local scale seasonal prediction of P. falciparum malaria infection. It could therefore be used to understand malaria transmission dynamics using meteorological parameters as the driving force and to help district health managers in identifying high-risk periods for more focused interventions. [ABSTRACT FROM AUTHOR]

Background: The development and propagation of malaria parasites in their vertebrate host is a complex process in which various host and parasite factors are involved. Sometimes the evolution of parasitaemia seems to be quelled by parasite load. In order to understand the typical dynamics of evolution of parasitaemia, various mathematical models have been developed. The basic premise ingrained in most models is that the availability of uninfected red blood cells (RBC) in which the parasite develops is a limiting factor in the propagation of the parasite population. Presentation of the hypothesis: We would like to propose that except in extreme cases of severe malaria, there is no limitation in the supply of uninfected RBC for the increase of parasite population. Testing the hypothesis: In this analysis we examine the biological attributes of the parasite-infected RBC such as cytoadherence and rosette formation, and the rheological properties of infected RBC, and evaluate their effects on blood flow and clogging of capillaries. We argue that there should be no restriction in the availability of uninfected RBC in patients. Implication of the hypothesis: There is no justification for the insertion of RBC supply as a factor in mathematical models that describe the evolution of parasitaemia in the infected host. Indeed, more recent models, that have not inserted this factor, successfully describe the evolution of parasitaemia in the infected host. [ABSTRACT FROM AUTHOR]