This paper presents an innovative approach to e-procurement in construction,which uses building information models (BIM) to support the construction procurement process.The result is an integrated and electronic instrument connected to a rich knowledge base capable of advanced operations and able to strengthentransaction relationships and collaboration throughout the supply chain. The BIM-based e-procurement prototype has been developed using distinct existing electronic solutions and an IFC server and was tested in a pilot case study, which supported further discussions of the results of the research. In the last few years, as an answer to the increasing need to reduce waste and improve performance, several innovative technologies emerged in the construction sector. New information and communication technologies (ICT) have challenged traditional working methods and stimulated change and modernization, especially in areas of e-business and building information modelling (BIM) –8. SlowlE-business platforms, which may take different forms , 10, plaConsidering these emerging issues, we propose an innovative approach to e-procurement in construction that uses BIM to support e-procurement processes. The hypothesis behind the proposed framework is that BIM-based solutions may reduce the negative effects of the fragmentation of the construction project lifecycle through the integration and integrity of information across the procurement processes in a project's life-cycle. This will imply new strategic approaches to the procurement cycle and support more accurate decisions. The result is an integrated instrument connected to a rich knowledge base capable of advanced operations and able to strengthen transaction relationships and collaboration throughout the supply chain.In order to achieve this purpose, the paper starts by reviewing the literature regarding e-procurement and BIM, focusing on major developments and most significant impacts on the construction industry. The paper then presents a BIM-based e-procurement model and respective prototype, which was developed to test the validity of the formulated model. Finally, the paper discusses the application of the prototype to a pilot case study, reporting the most important results of the research.According to several authors , 16 the ex-ante e-evaluation: refers to multicriteria evaluation of needs and procurement strategies;e-noticing: concerning electronic publication of public procurement notices;e-submission: concerning electronic submission of proposals;e-decision: concerning electronic evaluation of proposals, subsequent communication of evaluation results, and discussion and analysis of results;e-award: concerning electronic contract awards to suppliers with the best proposals;e-ordering: concerning all activities, including sending an order document from public buyers to suppliers, to the transmission of delivery instructions for ordered goods and services;e-invoicing: concerning claim for payment for goods and services ordered and delivered under agreed-upon conditions;e-payment: agreed electronic payment management and execution;e-contract management: refers to the use of electronic contract management instruments to monitor and improve contract performance and document management;ex-post e-evaluation: agreed multicriteria evaluation of the contract execution, and the eventual generation of KPIs to support future tendering processes.E-procurement is best viewed broadly as an end-to-end solution, which integrates and streamlines many procurement processes throughout an organization . Some ofIn a fully integrated and paperless context, all these processes should be combined and all relevant information must be available electronically. This will allow for a reduction of administrative work and automate operational processes, offering more time to think strategically . On the Considering its advantages, several countries are encouraging the implementation of e-procurement in the public sector . For insAgainst the technological potential of the existing electronic instruments, strategic perspectives on procurement and more integrated approaches to supply chains gain momentum and the integration of e-procurement with other industry-oriented ICT, such as BIM, becomes extremely important. The present research reflects this progressively paperless environment and effectively integrates these relevant technologies that are changing the construction paradigm.BIM has been developed in the last decade with the advent of refined computer aided design (CAD) systems able to enrich virtual 3D models of buildings with complementary data . As a new methodology, BIM promotes a more cooperative work between all specialties during the different stages of the construction project and also used during the life cycle of the building allowing a more efficient use of resources, decrease of errors due to lack of information/communication, and a more efficient management of the building operations costs , 23, 24.Increasing use of BIM has been seen in the last few years , 26. ThiSeveral authors point out that the true benefits of BIM are obtained when the technology is applied throughout the project lifecycle, from design to demolition . HoweverThe construction industry is gradually starting to understand the importance of interoperability in order to achieve integrated and automated work processes, with savings in cost and time . As moreIn an interoperable scenario, BIM is a powerful tool to support lifecycle integration  and in tHaving all the information centralized in a specific model may increase process efficiency and accurateness. As Ma et al.  mention,In a paperless, interoperable, and information-based environment such as the one encouraged by the use of BIM, interesting synergies can be generated by combining BIM with other ICT, such as e-business platforms. This combination results in hybrid electronic platforms capable of several advanced operations. Asite  is an extwo universities, mainly responsible for the coordination and development of the scientific work;an e-procurement service provider that provided the e-procurement platform and respective web services;a software house specialized in project management software applications, which provided support on project management features;a network of construction partners who gave important feedback on the project and participated in the simulation test.The present study was developed as an action research  conducteexploratory study and proposition of a BIM-based e-procurement framework;development of a prototype of the solution proposed;simulation and test of the prototype developed using a pilot case study, an experiment with a fixed approach, and a controllable environment.All participants gave rich, full insights and participated proactively. This participative and collaborative process were based on cycles, each of which comprised several steps: planning, action, and fact-finding about the result of the action. These cycles converged on better understanding the problems and phenomena throughout a learning process based on continuous refinement of methods, data, and interpretation . In the In the following sections, the most important developments and outcomes achieved during the three major phases of the research are presented, with special attention to the critical issues faced.Joining developments in ICT and procurement in the AEC sector, the authors consider that a BIM-based e-procurement solution not only makes more advanced and intelligent approaches to e-procurement systems possible but also promotes the generation of large electronic and interoperable networks that interact dynamically. The rich information-based environment that is thus created not only strengthens the automation of many operational tasks but also enhances information and knowledge management. This supports more accurate decisions and strategic approaches to the procurement cycle and potentiates more effective collaborative planning, collaborative design, integrated decision, scenario analysis, product comparison, document automation, processes automation, contract management, and performance management. This shifts from traditional e-procurement approaches, where CAD files are exchanged but are mainly used by each agent to print and recreate their own information models, not reusing or integrating information and not contributing to reduce construction projects fragmentation, recognized as a major hindrance to increase construction productivity. With BIM-based e-procurement, information may indeed flow in a more seamless way across application of the various agents within procurement processes.The proposed solution allows any user to initiate an e-tendering process using a BIM model. For instance, if a contractor wishes to purchase a specific product for a building, he can select that product (or related element) in the BIM model and launch the tendering process using the electronic platform. Automatically, all the necessary information is obtained from the model and the tendering is initiated.It is important to note that the use of BIM for procurement purposes demands a very detailed model, including all necessary information to launch the tendering process, which is a major challenge. Every BIM element must include several information sets such as work results related to each element or product identification (or types of product) in order to allow for the implementation of automatic procurement procedures. The association of this information to BIM elements can be made using the method presented in Although the links must be created manually using taxonomies available, information should be automatically included in the IFC model. To automate this operation the electronic platform should be connected to a BIM server, which should allow creating a new property set in the IFC file in which it includes the information previously associated with BIM elements. It is possible thereafter to initiate the e-procurement process in a simple way . SelectiIt is important to understand that some information is not easily included in the model. This makes it imperative that the system be able to attach files to elements of the BIM model. In this sense the system should create connections between messages and/or files and the elements of the BIM model. By selecting a determined BIM element , it should be possible to attach and access all the information related to it, not only information within the model but also external information connected to the model previously  . This feThe first step toward prototype development was to model traditional workflow for the construction e-procurement lifecycle, which included identifying the various players and respective value-added activities, information flows mapping, and determining major deliverables and decision points.Providing a standard visualization mechanism for business processes defined in an execution-optimized business processing language , businesThe resulting BPMN diagrams supported the development of a functional matrix in which the functionalities of the platform for each phase and each type of user were identified that considered information requirements identified previously. Considering the functional matrix and the BPMN diagrams, the use cases were then defined and, in accordance to use case specifications, front-ends were constructed. Microsoft SharePoint was the instrument used to implement them based on a form metaphor structure consisting of a series of forms (pages) with which the user interacts. Each form contained a number of fields that display output from lower layers and collect user input.To support the BIM-base procurement framework previously described, the electronic platform  was developed integrating and combining four different preexisting solutions. Microsoft SharePoint 2007 was used as the business collaboration platform system and as the front-end and to implement a set of workflow and rule-based procedures for the e-procurement. The EDM Model Server from Jotne EPM Technology was used to implement BIM-based features such as storing and manipulating IFC models. The IFC Engine Viewer provided by TNO was used as an IFC 3D viewer. Vortal eGOV is an e-procurement platform for the AEC sector. The IFC version considered was the IFC2x3 version.presentation layer: providing the application user interface and involving forms for smart client interaction and ASP.NET technologies for browser-based interaction;application services layer: implementing the business functionality of the application, comprising a number of components implemented using one or more NET programming languages;Business/interoperability services layer: supporting business services connected with external services using SOAP;data layer: providing access to external systems such as databases.The disparate electronic instruments work seamlessly in an integrated way through Web-services connections. The platform generic technology architecture was grounded on the combination of the latest architectures like model-driven architecture (MDA), the service-oriented architecture (SOA), cloud computing, and building information model (BIM)—the SOA4BIM Framework –49. The In the present case the EDM server component was used to perform IFC operations and the client application has been fully developed using Sharepoint framework. Considering the specific requirements of the research project, new information models have been designed and implemented on the EDM server in order to allow an efficient management of the project data  and defiIn order to link the BIM elements to the tasks, a connection between the EDM server and the software Primavera CCOP has been implemented using the web services. This allows the EDM server to send information to Primavera CCOP, which generates the list of elements based on the Uniformat standard and supports the manual linking of these elements to the respective work results.viewing and manipulating IFC models, providing access to all the information contained in the models ;managing tasks and other information related to each BIM element, from which it is possible to initiate the e-procurement process using the connection implemented with the Vortal e-procurement platform.The BIM-based interface was created according to the proposed solutions and supports two major advanced features:As mentioned above, the IFC engine viewer used (provided by TNO) is an IFC viewer with an advanced content mapper based on internal queries, which allows visualizing and interacting with 3D models. It has been embedded in the platform as an applet and integrated in the platform information flows.The PLAGE platform prototype was tested using a pilot case study based on a public sector project focusing on the renovation and expansion of a public secondary school, the Liceu Passos Manuel. The public entity responsible for the work provided all necessary documentation, including detailed design, specifications, and contract, and interacted with the research team to explain the most important features of project design and construction. Several other entities, such as major contractors and designers, also provided useful insights to enrich the research study. Throughout the pilot case several issues were addressed regarding the implementation of the innovative BIM-based e-procurement solution developed.To test the prototype, the design and a part of the procurement process inherent to the Liceu Passos Manuel school project were simulated. The pilot case was structured in 13 major steps, shown in viewing and manipulating BIM models created throughout the pilot case and accessing inherent information;using BIM model viewer to attach external files to the model;launching RFQ and RFI (requests for information) using BIM-based e-procurement interface;initiating e-procurement process based on the elements of the BIM model;submitting a proposal using the BIM-based interface.Throughout these steps the BIM-based e-procurement prototype was tested in various ways, including the following:A brief description of each step is presented below in order to clarify the entire pilot testing process.Step 1. In this initial stage several BIM models have been created (the designs provided were in 2D), which were used to test consistency of the BIM-based interface and PLAGE BIM management module. The modeling process reflects four modeling steps with increasing design detail and follows the BIM directives adopted in other countries ( American Institute of Architects (AIA) identifies several levels of detail for models that correspond to different project phases [ountries , such ast phases . Beyond Step 2. This step focused on the enrichment of the BIM model with information and Uniformat codes, which were manually included in each BIM component. For success, this process requires careful modeling  to guarantee that the model is close to reality. The development and use of a BIM objects' library already including all the needed information is recommended.Step 3. The IFC models were automatically generated from the BIM models originally created in the Archicad proprietary format. IFC interoperability concerns were given special consideration during this transformation. Particular attention was given to the problems that may arise due to the lack of interoperability between proprietary formats and IFC formats. As stated by Lipman et al. (2011), user expectations on IFC interoperability are not being met by CAD applications, which have been granted IFC certification and should be able to exchange 100% of the information in their CAD models via IFCs 100% of the time; however, they argue that the use of more adequate and systematized conformance and interoperability testing methodologies may lead to good results in terms of IFC interoperability. Meanwhile, in order to prevent major problems in IFC transformation operations, a careful analysis following IFC file generation should be conducted to assess possible errors. Special attention should be given to ground, materials, tailor-made objects , and specific elements subject to any advanced operation conducted by other BIM software . Despite interoperability issues, IFC is crucial to collaborative work to facilitate a multisoftware approach to projects and to drive performance of construction supply chains to higher levels of interoperability [rability , 53.Step 4. This step begins with the login of the user to the PLAGE platform and the subsequent upload of the BIM model. This step may be repeated throughout the design process.Step 5. According to the information models implemented in PLAGE platform, the EDM server stores and manages the IFC file and sends all relevant information to the Primavera CCOP software through web services. Subsequently, Primavera CCOP lists all of the construction elements using Uniformat based on the IFC tree view.Step 6. This step focused the manual link between each BIM model component and the corresponding tasks . Step 12. In this step suppliers used BIM viewer interface to add prices to BIM components, using a form or linking external files (such as pdf) to BIM components. The EDM server includes price information in the IFC file and creates pointers to external files that the supplier might submit. Step 13. Finally, a multicriteria evaluation tool was used, implemented on the PLAGE platform in order to support the proposal's evaluation. It can be based exclusively on price or various criteria [criteria .The proposed solution of BIM e-procurement was designed with the aim of providing a richer approach to the information flows associated with procurement, as it may foster more strategic approaches to e-procurement, by improving information management potential, stimulating collaboration, and maximizing supply chain management. In traditional e-procurement platforms, collaboration arises primarily from buying requirements for procurement through the specification development process, using real-time communication and exchange of information , 57. HowThe chosen case study research design consisted in a qualitative research, which allowed a description of the interaction of context and actors in a specific setting . While tFrom this specific case study, and based on the expertise of the interviewed professionals, it is possible to sustain that BIM-based e-procurement may reduce the time and effort variables related with information management activities that have heavy contractual and administrative procedures and documentation, as BIM model will serve as a unique repository to all this information, both to the owner, contractors, designers, or subcontractors. Moreover, it is expected that as the various agents involved in the procurement process may reuse BIM elements, buyers and suppliers will enhance the integrity and reliability of information used, diminishing the errors due to information operation. These benefits were clearly identified by the interviewees in qualitative research but it was not the focus of the research to measure or quantify these benefits.However, these benefits are shadowed by the costs associated with the required additional effort to edit the documents and linkages to the BIM model and maintain a procurement process using coherent information between product model, quantities, product descriptions, and contractual arrangements centered on a BIM model. This editing requires currently specialized technical support to combine the various information sets into the BIM-based procurement process. Although the traditional process also requires editing a substantial part of the information for the procurement process, the effort does not require a unified treatment of documents and there is a more fragmented approached to information and documents management. Indeed, the approach requires a deep understanding about how to create the models and how to classify the information included in the models using predefined taxonomies and linkage of vectorial and nonvectorial information within a BIM Viewer.Although the research project did not accurately measure the additional effort for the procurement process in comparison with traditional procurement mechanisms, the various partners involved in the process recognized that the learning curve was considerable and that it did not make the new administrative process overall more streamlined. Although the BIM-based e-procurement interface has shown itself to be useful, the success of its implementation requires a deep understanding about how to create the models and how to classify the information included in the models using predefined taxonomies. This issue is very important as in construction projects procurement of trade services and products tends to be a one-time activity, and thus there are few opportunities for gaining efficiency due to replication of the process. Moreover, there were several difficulties that emerged with the pilot case study that were not anticipated.A fundamental hindrance was the ability to convert individual building objects in aggregate product and service “blocks” that are released to tender. The major problem is on the level of aggregation, because BIM objects tend to be very elementary and tenders focus on aggregate levels of products and services. Quantities for tendering are easy to obtain directly from the BIM model, but how to organize the elements to be tendered is a rather complex issue, and the existing models do not reflect this need. It is easy when the blocks are windows, doors, or other highly specific products but it becomes considerably harder when there is a need to aggregate with works that involve other types of products or trade services.Some problems were identified regarding the interoperability models: when transformed into IFC the models lost some information included in the original proprietary format. It was also found that there are no specific IFC classes for procurement related information, which can hinder interoperability in procurement processes. Furthermore, it was evident that the wide implementation of the solutions proposed depends to a great extent on the dissemination of standardized taxonomies. Using predefined information classifications for BIM elements, work results, products, resources, and so forth cannot be avoided because these classifications must be common to the various actors to guarantee that the same codification will be used for a specific piece of information. This is particularly important whenever information flows across organizational boundaries, from procurer (buyer) to tenderer (supplier) that may have different modeling configurations and working practices that should be previously aligned.Although the research project has uncovered several hurdles, the BIM-based e-procurement prototype presented in this paper demonstrated successful results. The parties involved, including the owner of the building and one of the major national general contractors, considered the solution opportune and useful and reported the importance of stimulating increasingly integrated and collaborative processes using innovative ICT. Several benefits have been identified as quite promising in terms of replicating the pilot in other full-scale construction projects. First, the need for the procurement process to input information in the BIM model has proven to be very useful as the model becomes a natural repository for all technical, managerial, administrative, and contractual information about the project. Indeed, rather than having several digital repositories of the project, agents in the project have a user-friendly interface—the BIM Viewer—for the most important documents facilitating the search, retrieval, distribution, and storage of documents and information, because they are connected to the model. This is particularly useful for all contractual procurement administrative documentation, as in construction projects these are a large part of all information. Hence, though the approach adds to the size and complexity of the BIM model, it significantly improves information management.Second, as the buyer triggers the procurement workflow the IFC exportation of the technical and contractual data from the BIM model to the platform occurs. In addition to the architectural designs and specifications, the platform also releases the tender documents and the templates for the bid reply of the suppliers. In this process complementary information may be added, such as expected dates for execution, maximum price, selection criteria, and so forth. However, this information is incorporated in the tender documents through a structured procedure that also feeds the original BIM model. Hence, a fair amount of reusability is possible, in both directions, of the information, models, and data between agents. Of particular value is the fact that buyers and suppliers can avoid the reentry of data and re-creation of models, with all the errors and misfits that typically occur in these replication processes.Although there was a major effort to have mainly structured information in the e-procurement process, the platform also supports some complementary unstructured information in the tender document sent by the suppliers. As a result, the BIM-IFC detailed design and the filled-in bid template may contain additional information in the form of attached files  or possibly Web links. However, each element of unstructured information has to be linked to an object within the BIM model. This complementary information and documentation may also be incorporated directly in the BIM Model , through the manipulation of the BIM Model Viewer, thereby enriching the content of the model.The research includes some limitations related to its complex approach . Such research is demanding in terms of planning and management. In some instances the research is unable to offer complete answers to the questions raised, so the approach focused primarily on the problem setting than problem solving. Nevertheless, it achieves results reflected in various viewpoints that enrich the state of the art and leverages the pertinence of final findings.


In the US, colorectal cancer is the fourth most common cancer and the second most deadly. Screening is recommended, not only to reduce mortality, but to prevent cancer by detecting precancerous polyps. Many screening methods are available now, and newer methods based on molecular markers show promise for the future. In the US, colorectal cancer is the fourth most common cancer, after breast, prostate, and lung cancers, and the second most deadly cancer after lung cancer; it will kill an estimated 50,310 Americans in 2014 [New England Journal of Medicine in 1993 [The Lancet.Colorectal cancer screening was first evaluated by a study in Minnesota that started in 1975 and was published in the  in 1993 . The inv in 1993 , studiedNew England Journal of Medicine paper [The original Minnesota trial reported in a later ne paper  that annne paper -8. From In the US, several groups, including the US Preventive Services Task Force, the American Cancer Society, and the American College of Gastroenterology, have published guidelines for colorectal cancer screening . They cuFOBT is a test of stool samples for the presence of blood. Some are simple chemical tests (guaiac FOBT) and some are fecal immunochemical tests (FIT). Either form of FOBT is acceptable as long as it is sensitive enough to the presence of blood. The presence of blood is considered a positive test and indicates that the patient may have cancer or advanced pre-cancerous adenomas and requires follow-up with colonoscopy. Colonoscopy is an endoscopic method used to visualize the whole colorectum. Flexible sigmoidoscopy examines only the lower part of the colon and rectum, and if cancer or adenomas are found, follow-up with colonoscopy is also required to complete the examination. Although randomized trials have not been done to show colonoscopy's benefits, the efficacy of both FOBT and flexible sigmoidoscopy depend on colonoscopy to follow up findings on those tests.Other tests that are available but not universally recommended are double-contrast barium-enema X-rays; 'virtual colonoscopy', a method of using computed tomography to visualize the colon using contrast media; and stool DNA tests that look for additional molecular biomarkers in the stool as well as occult blood. As more is learned about these methods, they may be more widely adopted.The effectiveness of colorectal cancer screening so far is demonstrated not only by the decline in mortality that exceeds what is expected from improved treatment, but also by the steady reductions in incidence that have been observed in the US since 2006. However, about a third of the people who can benefit from early detection of colorectal cancer are not getting screened , and somNew England Journal of Medicine [Three recent studies, all in the Medicine -13, thatThe second study used a cohort of individuals some of whom had undergone sigmoidoscopy or colonoscopy during the 20-year follow-up period to evaluate the impact of that procedure on incidence and mortality from colorectal cancer . AlthougThe third, most recent, study evaluated a test of DNA markers in stool . Stools How to increase the uptake of colorectal cancer screening in the asymptomatic population for which it is intended has been the subject of much research. Unlike other cancers for which early detection is recommended, colorectal cancer offers a number of choices for screening methods. This is both a blessing and a curse: a blessing because it allows flexibility in addressing the preferences and concerns of an individual considering screening, but a curse because it makes the public health message about screening less tidy and potentially more confusing ,15. A raNew England Journal of Medicine paper detailed above [KRAS point mutations in addition to an FIT. Several groups are working on molecular markers that can be found in blood, including proteins such as carcinoembryonic antigen, mutated genes such as KRAS [SEPT9 (encoding septin 9) [Increasing the performance of non-endoscopic screening methods as well as making them more acceptable to the individual are the primary benefits of genomic, epigenomic, and other molecular early detection markers. The stool DNA test in the recent ed above  uses a p as KRAS ; hypermeeptin 9) ; and miceptin 9) .Although to date none of these blood markers has been proven adequate for screening, there is a good chance that one or a panel of such markers will eventually be discovered that is sensitive and specific enough for screening, much like what was done in the stool DNA test. Many believe that a blood test would help boost uptake of screening by providing an alternative to those who want neither endoscopy nor a stool test. The robust and rapid uptake of prostate-specific antigen (PSA) testing for prostate cancer despite the lack of clear evidence of efficacy can, in part, be attributed to the fact that it is a blood test and can be administered as a routine part of a standard physical in which blood is taken for cholesterol, glucose, and other substances. A similar test for colorectal cancer with the added benefit of clear evidence of efficacy should drive uptake of screening closer to the ideal 100% of the 50-and-over asymptomatic population. Given the rate at which molecular methods are becoming more and more precise and sensitive, I am optimistic that this goal is not far off.


Scoliosis and Spinal Disorders. We feel that with the ever-changing landscape of spinal conditions as well as health-care utilization and the need for a forum to voice cutting-edge and multidisciplinary spine research worldwide, [With the start of 2016, we at the journal would like to wish all our readers, reviewers and Editorial Board members a most happy and prosperous new year. Ushering in this year, the journal has made some considerable changes. For one, the journal has been renamed Scoliosis journal as its official journal and Dr. Hans-Rudolf Weiss became its first Editor-in-Chief [Scoliosis and Spinal Disorders. Currently, the journal remains an open access, multidisciplinary, peer- reviewed publication that focuses on original, primary research articles as well as broad narrative/systematic reviews and meta-analyses. The journal is indexed in PubMed and in numerous other major search engines. BioMed Central remains the publisher of the journal.The start of a new year is also a time for reflection. In order to understand where we are headed, we must acknowledge and appreciate where we have been. After 2 years since the formation of the Society on Scoliosis Orthopaedic and Rehabilitation Treatment (SOSORT), the board of the society launched in 2006 the in-Chief . Dr. WeiSpeed of publication – The average time of article submission to acceptance is currently 42 days. We aim to have articles fully published and indexed within one month of acceptance.Flexibility – The journal has no limits to color images and number of authors for published articles. The journal also encourages deposition of datasets and other supplemental information to accompany the articles, such as multimedia. Articles are also provided links to PubMed and other relevant articles.Full disclosure – The journal firmly believes in full disclosure and transparency. As such, in addition to the authors’ disclosure statements, reviewer comments will also be available online to accompany the published article.Worldwide accessibility and open access – All published articles are available for full download without any fees to the reader or institution.Indexing – All published articles will be automatically indexed in PubMed, and in over 40 other abstracting and indexing databases.Optimized reach – The BioMed Central website has over 9 million visitors each month. In addition, a dedicated marketing and public relations team exists to help disseminate the published material within and beyond the academic community. Various tools  will be utilized to disseminate the research findings in a timely manner and to maximize impact.Article metrics – The journal will track the number of times the article has been accessed, cited, covered in the media and blogs, shared via social media , and bookmarked/rated/discussed via bibliographic tools/sites . This service will further give both the authors and readers an indication of the global impact of the article.Personalized approach – The Editors-in-Chief and Editorial Board will provide a personalized and rapid attention to the needs and concerns of the authors. The Editors strive to perform thorough, fair and constructive peer review of all manuscripts, and in line with guidelines and best practice recommendations issued by organizations such as the Committee of Publication Ethics (COPE), and journal policies [policies .Although the journal has enjoyed a rather auspicious start and sustainability, it has also managed to remain at the forefront of medical publishing. Some of the strengths of the journal are as follows:We invite you to join us in embarking in a new era for the journal – a new frontier in the review, publication and dissemination of research and knowledge of spine disorders and conditions. These new beginnings will entail a multidisciplinary approach to spine research, a globalization of broad spine topics, rigorous peer-review, expeditious publishing and continued open access, utilization of social media and other platforms to maximize reach and impact, and quality-driven evidence-based spine care in scientific reporting.


To investigate if the psychometric qualities of an OSCE consisting of more complex simulated patient encounters remain valid and reliable in the assessment of postgraduate trainees in general practice.In this intervention study without control group, the traditional OSCE was formally replaced by the new, complex version. The study population was composed by all postgraduate trainees (second and third phase) in general practice during the ongoing academic year. Data were handled and collected as part of the formal assessment program. Univariate analyses, the variance of scores and multivariate analyses were performed to assess the test qualities.A total of 340 students participated. Average final scores were slightly higher for third-phase students . Overall test scores were equally distributed on station level, circuit level and phase level. A multiple regression analysis revealed that test scores were dependent on the stations and circuits, but not on the master phase.In a changing learning environment, assessment and evaluation strategies require reorientation. The reliability and validity of the OSCE remain subject to discussion. In particular, when it comes to content and design, the traditional OSCE might underestimate the performance level of postgraduate trainees in general practice. A reshaping of this OSCE to a more sophisticated design with more complex patient encounters appears to restore the validity of the test results. Features such as test content and test setting are controllable and modifiable, but must address the target students. With respect to the workplace- based learning concept and in agreement with the learning objectives, the undergraduate OSCE will therefore focus on basic skills  with or without simulated patient contact. Further on in the curriculum, the OSCE scope will turn to more comprehensive patient encounters and addressing specific tasks .8The objective structured clinical examination (OSCE) has been used since the early 1970s to assess undergraduate and graduate medical students’ skills and competence in simulated patient encounters.9In general, students are better educated, higher skilled, and (fairly importantly) more confident with test and assessment proceedings. First, the concepts of workplace-based learning and the more sophisticated version termed ‘real- life learning’ penetrated the curricula.11 Second, many contemporary curricula provide comprehensive testing, feedback, and remediation programs for every student.13In a setting in which educational concepts are rapidly changing, a revisiting of the OSCE should be considered. 14Parallel to these changes in the educational environment, the assessment strategies and proceedings need to be reshaped.15 In other words, at this stage trainees were confronted with the more complex reality of consultation, while the OSCE focused on single aspects of patient encounters.Given this point of view, the OSCE might benefit from a remodeling for postgraduate trainees in general practice. The content reliability of the OSCE when addressing this particular student population is a topic of discussion at the four Flemish Universities (Belgium). Specifically, in the past three academic years, mean OSCE scores rose remarkably (up to 75/100). This observation coincided with preserved psychometric qualities, which were expressed as reliability and validity. After meticulous revision of the past OSCEs, the most feasible explanation appeared to be that the test content had been insufficiently adjusted to the qualification level of these ‘professional students’.This pilot study addressed the following research question: do the psychometric qualities of an OSCE consist- ing of more complex simulated patient encounters remain valid and reliable during the assessment of postgraduate trainees in general practice? To provide complexity to the encounters, the OSCE introduced more than one focus, addressed more than one theme, and formulated more than one instruction per station.The study population consisted of the second- and third- phase postgraduate trainees in general practice at the four Flemish Universities . The GP-master comprises 3 years of a combined internship and academic education. Evidently, there were no exclusion criteria. Participation in the OSCE is mandatory, as it is part of the formal program assessment. However, postgraduate trainees that pass the OSCE during the second phase are rewarded with an exemption from this exam during the third phase.The study was officially approved by the Medical Education Advisory Board, which is composed of students, teachers, and the heads of department of all four universities involved. Ethical approval is granted by the Medical Ethical Advisory Board of all four universities for educational research during the ongoing academic year. Following the national legislation, informed consent of the study population is only required when patients are involved.The traditional OSCE was formally replaced by the new, complex version. This alteration was officially approved by the Medical Education Advisory Board, which is composed of students, teachers, and the heads of department of all four universities. Students were officially informed about the proceedings and about the changes in exam structure and content.The development of the complex OSCE was preceded by debates with experts, students, and teachers. Above, a comprehensive analysis of the OSCEs from the past 10 years and a review of literature were conducted. A new protocol was developed that contained script conditions and instructions for the observer and simulated patient training. The blueprint of the OSCE was framed with respect to the learning objectives of the GP-master. Four experienced script-writers  each produced eight stations in deliberation with their assistants and staff members. During the next stages, all OSCE scripts repeatedly passed the review and revision process. In total, 32 scenarios were written. The complexity of the OSCE was defined as the integration of two or more skills in one station. This approach more closely reflects a realistic situation, while preserving the structured and standardized character of the assessment.Each scenario was constructed to embody two reasons for the encounter, instead of a single reason . Both reasons were content-related to avoid unnecessary confusion and pitfalls. For example: ‘a father has been referred to a GP by the school doctor of his 6-year-old son. The boy is overweight. Aside from this announcement, the father has some questions based upon irrational beliefs about the boy’s flat feet, assuming that this condition requires treatment before the boy can begin to participate in sports’.The simulated patient (SP) was instructed to spontaneously mention the first reason for encounter. When students asked whether there were any other concerns, the simulated patient released additional information and disclosed the second (related) reason for encounter. To avoid the post- graduate trainee completely missing this second concern (and undeservedly failing this station), the SP was instructed to release the necessary information after a certain period of time. Students who did not spontaneously elicit both announcements were penalized on the item checklist (item: ‘student spontaneously elicits second announcement’).Consequently, the instruction to the student was multifaceted. Students were asked to address two or more issues, for example: ‘take the anamnesis, discuss your findings, and give information’. Supplementary information about the clinical examination, lab results, medical history, etc. was available if required. This option guaranteed that the OSCE retained it structured and standardized character.Observers were accurately informed in advance. Prior to their actual involvement, they received a document in which the test-outcome problem was illustrated and the modification of the OSCE was explained and justified. Observers participated in group training just before the start of the OSCE. They were informed about assessment strategies and the general test-outcome, their task as the observer, the construction of the OSCE script, and the scoring system. To set the standard for each station, the observers were asked to score each student’s performance independent of the item checklist (borderline regression method). To estimate the inter-rater reliability, certain stations were observed by two independently scoring observers.The item checklist was accompanied by legends. The legends contained scoring instructions, illustration of skills, competencies, justification of items, etc. This option reduced the risk of discussion and inter-rater variability and enhanced the observers’ examination competence. Although the contribution of each item on the checklist to the maximum test score was weighted, observers were blinded for this intervention. Observers were also asked to assign a single score for each student’s performance on the station. This score was used to set standards (borderline regression method).Results were analyzed with the aid of SAS version 9.1.3 and Excel 2010. Univariate analyses were performed to manage and explore the data (PROC UNIVARIATE in SAS). We calculated the variance of score in between the two master phases, in between stations, and in between circuits. The circuits varied across the different sessions, requiring a multivariate analytic approach to assess test qualities. Cronbach’s alpha was not considered a satisfactory method in this multivariate analysis. Nevertheless, this reliability coefficient was calculated and described for a randomly selected number of stations (at station level and item level). A multiple regression method was used to measure the variability and distribution of test scores among the different stations, circuits, and master phases (second or third). This procedure was performed using the PROC MIXED statement in SAS. Finally, the borderline regression method was used to test the reliability of the scoring system.Of the 32 newly developed stations, 24 were distributed over 40 different circuits. Eight stations were not included because they were considered inappropriate or did not meet the quality requirements after revision by the expert group (see METHODS). The features of the students are presented in Standards were set using the borderline regression method. In this pilot study, a new format of the OSCE was tested in response to an increase of test scores with preserved psychometric qualities over the years. The test qualities of a more complex OSCE were studied. Students in the second and third phase of the GP master were assessed with an OSCE that consisted of eight 12-minute stations. Average test scores returned to acceptable results (14/20 or 70%), with a performance-based cut-off score of 11/20 and an overall failure rate of 5%. Overall test scores were equally distributed at station, circuit, and phase levels. The variance of score per station and per circuit on the overall test score was significant. Although Cronbach’s alpha was not with- held as an appropriate test method, values appeared acceptable to good at inter-station, inter-circuit, and item levels.In past years, students’ test scores on the traditional OSCE rose in the Flemish Interuniversity GP Master. Psychometric reliability and validity remained stable but content reliability failed. Consequently, a team of experts, staff members, and students participated in a discussion in search of an acceptable explanation. First, the past OSCEs were revised. In the junior-GP postgraduate education program, an OSCE is scheduled in the second and third phase of the GP master. For 15 years, a circuit of 20 8- minute stations was conducted following the ‘traditional’ and well-described method. The simulated patients were highly experienced and intensively trained, and they adopted various roles. Observers were recruited from the pool of internship supervisors. They were all experienced in work- place-based assessment and they were trained before enrollment in the OSCE. The blueprint of the OSCE was framed in agreement with the qualification requirements of the target students. Validity and reliability testing was performed after each session, and standard setting was performance-based (borderline regression method). Test qualities were systematically found to range from good to very good. Over the years, the OSCE was not subject to context changes.17 An increase in examination time, an increased number of stations, and assessment by more than one observer were proposed as promoters of test quality. On the other hand, scores on some subscales of the OSCE  appear to be more reliable than scores on other scales .18 Even the design (context) of the OSCE was, for unclear reasons, recognized as a moderator of the estimated reliability 6. The fact remains that validity testing of an OSCE is a hazardous piece of work: content validity, construct validity, and concurrent validity testing are subject to many moderating and uncontrollable factors.4Second, the literature was searched thoroughly. Reviews and meta-analyses regarding the test qualities of OSCEs concluded that reliability as expressed by Cronbach’s alpha of overall test scores is only moderately acceptable (0.60 or lower).21 The intervention of a validation committee guarantees that a standardized and objective methodology is used to develop an OSCE. The content is determined and monitored by the learning objectives.22 In contrast the specificity of the OSCE design is barely addressed in curricula development and in research. Aside from a consensus on the number of stations and examination time, no other regulations are defined.16 Traditionally, each simulated patient encounter focuses on one particular theme, discloses one single announcement  and targets one main instruction. In the light of a rapidly changing educational environment, this approach might underestimate the learners’ competences and skills. In the case of the GP master described in this study, it was concluded that the original OSCE was not sophisticated or complex enough to adequately assess the performance of future GPs.Finally, a team of experts discussed the above findings. Since the benefits of OSCE testing are always precariously balanced against cost, the construction and content of this assessment concept require full attention.Therefore, the traditional OSCE was extensively reshaped (see METHODS). Each patient encounter was initiated for more than one reason, and therefore focused on more than one theme and provided instruction on more than one competence. Because the changes were intended to increase the complexity and sophistication of the stations without increasing their difficulty, no pitfalls, rare diseases, complex medical problems, or other confounders were included. The scenarios were constructed similar to encounters in daily practice.The distribution of the overall scores, as well as the distribution of the scores per station, per circuit, and per phase, demonstrated that the revised OSCE is reliable from a psychometric point of view. Although conventional reliability testing was deemed inappropriate (and therefore only conducted for a random sample of stations and circuits),Cronbach’s alpha was moderate to high. This statistical approach was not considered because it addresses single component facets and does not address the overall normality of distribution.The content and concurrent validity were not specifically addressed. However, median and mean scores appeared comparable over the different score levels . Second, the significant concordance between the item score and the observer score is an argument in favor of content reliability. All observers were highly experienced in assessment and in education, and they were blinded to the weighting of each item on the itemized checklist. They referred the performance of each candidate to the target student that they teach and train in practice.This study has some important limitations. Twenty-four new stations were developed and tested in 40 different circuits. Each circuit was composed according to the formal blueprint of learning objectives. A more homogenous construction of the circuits certainly would have benefited the power of the study results and facilitated the analytic process. Consequently, inter-rater reliability was not reproduced in a reliable way, since the number of stations per circuit was low. Only a limited number of stations were observed by two separate observers. The results were reassuring, but not robust enough to report. Second, one major barrier in the implementation of an OSCE is the price tag. It is obvious that a circuit of eight 12-minute OSCE stations is far less expensive than a traditional OSCE. Evidently, the burden of all participants must also be taken into the final account. In this study, feasibility, acceptability, and cost-benefit analyses were not addressed.The first strength of this pilot study is that it was initiated and elaborated by a focus group consisting of experts, staff members, and students. Advice was also sought outside the faculty, and the final version of the test was presented to the panel members again. Second, both observers and simulated patients were recruited from the core pool. All were highly experienced and well instructed on the new OSCE design. Third, the results were very reassuring. As hypothesized, mean and median scores returned to acceptable values with preserved test qualities.In a changing learning environment, assessment and evaluation strategies require reorientation. The OSCE is considered a reliable tool to assess the clinical and vocation- al competencies of medical students. However, its reliability and validity remain subject to discussion. In particular, when it comes to content and design, the traditional OSCE might underestimate the performance level of postgraduate trainees in general practice. A reshaping of this OSCE to a more sophisticated design with more complex patient encounters appears to restore the validity of the test results.Future research should repeat this pilot study to confirm test results, refine the concept, and define optimal test conditions.


To collect, organize and appraise evidence of socioeconomic and demographic inequalities in health and mortality among the older population using a summary measure of population health: Health Expectancy.A systematic literature review was conducted. Literature published in English before November 2014 was searched via two possible sources: three electronic databases , and references in selected articles. The search was developed combining terms referring to outcome, exposure and participants, consisting in health expectancy, socioeconomic and demographic groups, and older population, respectively.Of 256 references identified, 90 met the inclusion criteria. Six references were added after searching reference lists of included articles. Thirty-three studies were focused only on gender-based inequalities; the remaining sixty-three considered gender along with other exposures. Findings were organized according to two leading perspectives: the type of inequalities considered and the health indicators chosen to measure health expectancy. Evidence of gender-based differentials and a socioeconomic gradient were found in all studies. A remarkable heterogeneity in the choice of health indicators used to compute health expectancy emerged as well as a non-uniform way of defining same health conditions.Health expectancy is a useful and convenient measure to monitor and assess the quality of ageing and compare different groups and populations. This review showed a general agreement of results obtained in different studies with regard to the existence of inequalities associated with several factors, such as gender, education, behaviors, and race. However, the lack of a standardized definition of health expectancy limits its comparability across studies. The need of conceiving health expectancy as a comparable and repeatable measure was highlighted as fundamental to make it an informative instrument for policy makers. Between 2000 and 2050 the proportion of the world's population over 60 years is expected to double from about 11 percent to 22 percent, according to WHO estimates , mortaliThe main advantage of health expectancy is that it captures both the “quantity” and “quality” of life dimensions of health. As it combines information on mortality and health, it is more informative than life expectancy to forecast expected healthcare costs and assistance needs, as well as to plan pension systems and set age of retirement in a sensitive way; and from a societal point of view, it helps to anticipate possible changes in social participation and social inclusion at older ages. Information on health expectancy can be analyzed together with information on life expectancy, and their trends related to each other and compared to assess whether the proportion of life spent unhealthily is expanding due to the longer survival of individuals suffering from chronic diseases , or compOn the other hand, one of the drawbacks of using this measure descends from the fact that the whole concept of health expectancy depends on the interpretation given to “full health”. This has generated a variety of ways of expressing health expectancy, differing depending on the health indicators used to capture “full health”. Commonly used terms are disability-free life expectancy, active life expectancy, healthy life expectancy and years of healthy life. These measures are not directly comparable and one is not preferable to another. Authors often define health depending on the availability of the information they have access to or on the objective they want to pursue. The problems arising from this lack of standardization have already been pointed out  and effoThe widespread use of SMPH to measure and compare population’s health and the need of shed some light on the complexity and the uncertainty surrounding the concept of health expectancy have motived this systematic literature review. More specifically, the review seeks to collect and give systematic appraisal of studies exploring socioeconomic and demographic inequalities in health expectancy, focusing on the older population. Within this general aim, the first objective was to appraise the extent of such inequalities and observe which factors have been considered and which remain unexplored. The second objective was to assess the strengths and limitations of using HE to study inequalities in healthy survival, especially in terms of comparability of results across different studies and populations.In the next section our search strategy is described and the processing and selection of references are explained. Then, findings are organized and presented by type of inequality considered, type of health indicator used and methods applied to estimate health expectancy. Finally, gaps in understanding HE are outlined and limitations acknowledged.Two possible sources were considered for the literature review: 1) electronic databases, and 2) references in selected articles. Electronic databases were the main source: we used Web Of Science, Medline and Embase.health expectancy was declined using a number of expressions all referring either to physical or general health, such as disability-free life expectancy (DFLE), active life expectancy (ALE), healthy life expectancy (HLE). As the family of SMPH is quite large and heterogeneous, given the size of the literature that uses this measure, we decided to focus only on physical and self-reported health combined with mortality. We did not include studies focused on mental functions and cognitive impairments, even if these may cause disability at later stages. The target population-the study participants- of this search was older individuals. We did not use any specific age threshold to define old age, but general expressions commonly applied to identify older adults and the most frequently used age groups, such as 65+, were included among the keywords. The exposures of interest were socioeconomic and demographic variables. We used general terms, such as ‘socioeconomic factors’, as well as specific components, e.g. education or income, and a wide range of demographic terms including gender, marital and parental status, race and ethnicity. The search was developed to combine terms referring to outcome, exposure and participants of interest . The genTitles and abstracts of all references identified in the search were screened applying exclusion and inclusion criteria. The references shortlisted from this first screening were read in their entirety and selection criteria re-applied to full texts. The lists of references of the resulting studies were checked to ensure that all relevant articles were included in the search. Inclusion and exclusion criteria were set according to the definitions of the outcomes, exposures and participants and depending on the type of study . As for The findings of the studies included in this review were synthesized in a narrative format, and organized adopting different perspectives. Data were extracted using a customized template based on the PICOS statement and developed in Microsoft Excel including the following items: author, year, setting and country, participants, exposure, outcome, measure of outcome, methods, and source of data . ConsequTwo approaches are usually adopted to estimate HE: these are cross-sectional or longitudinal methods. The first typically employs prevalence-based life tables, also known as Sullivan’s Method . The secSullivan (1971) provided the first calculation of DFLE. The Sullivan’s method is the most commonly used  using incident rates instead of prevalence. In situations where longitudinal data are available, the incidence-based MSLT is preferred because it most accurately reflects the impact of current conditions  on the evolution of the target population. The MSLT model is an extension of the simple period life table that underlies standard life expectancy estimates, and it is the preferred method in analysis of health changes over time . TWhen prevalence and incidence remain constant between periods Sullivan’s method and multistate life table have been found to produce similar results . When eiFrom the combination of the three databases, 256 references were identified and screened after deduplication . After rFindings from the 96 selected references were organized according to two leading perspectives: the type of inequalities considered and the health indicators chosen to measure health expectancy.All studies selected in this literature review, but one, stratified individuals by age and gender . For example, some of the results from our literature review showed evidence of the gender paradox in Brazil,29,37–39The studies of racial inequalities in HE included in our search were all set in the United States ,54,69,70When socioeconomic position (SEP) is controlled for, racial inequalities are larger among lower socioeconomic groups, with low SEP Blacks being the most disadvantaged group . AccordiSEP can be measured via different indicators or their combination. The studies included in this literature review identify SEP using alternatively education, income, occupational or social class, area level deprivation, geographical area of residence , housing tenure, social support, or their combination ,47,72,73The strength of the association between SEP and HE varied across countries. It was substantial in the United States, while rIt was commonly found that socioeconomic differentials in TLE and HE were larger for men than for women. One of the possible explanations is that women’s SEP may be more a function of their household’s SEP than their individual characteristics ,73. AccoSEP-based differences in HE has been generally found to exceed SEP-based differences in TLE, suggesting that inequalities are most pervasive with respect to quality rather than quantity of remaining life ,64,72,73Since most studies measured SEP through education, special attention was dedicated to HE gap deriving from education-based inequalities. The main advantage of measuring SEP by education is that in most cases individuals have completed their educational path by their early adulthood and this indicator is therefore stable across ages. The vast majority of the studies included in this review confirmed the advantage of being highly educated in terms of both TLE and HLE ,72,73,75It is generally recognized that lifestyle factors are associated with both morbidity and mortality. These factors, in particular smoking, alcohol consumption, overweight and obesity, and physical activity, have also been found to be associated with SEP in several populations ,80 and tThe negative effect of smoking on ALE was confirmed in all studies ,88,89. AOne of the difficulties in comparing studies on HE derives from the heterogeneity of its definition. HE is a fairly generic measure that can refer to physical as well as cognitive status. This systematic review was focused only on the former, expressed both in terms of general health and disability. Disability however can be defined using a variety of indicators, and in some studies more than one indicator was applied. In the following paragraph and tables we present studies according to the measures adopted to define HE.This literature review aimed both at providing a systematic appraisal of studies that investigate socioeconomic and demographic inequalities in HE and giving a critical assessment of this measure. To our knowledge, this is the first review on aggregate/macro level measures of health expectancy in the older population to have been conducted systematically. A literature review on active life expectancy was published in 2002  but it wWith respect to the first objective of the review, two main results emerged. The first is the heterogeneity of the indicators and methods used to measure health expectancy and the multiplicity of terms chosen to name it. It was generally observed that DFLE and ALE were used interchangeably, while HLE mainly referred to life expectancy in good SRH, although this was not always the case. Even when HE referred to the same dimension of health  this was measured using very different indicators. Therefore, the different levels of HE reported across studies may partly depend on the way healthy and unhealthy conditions were defined and not just on the risk factors considered for the analysis. Some studies computed multiple types of HE using different health measures ,63–65,93The other aim of the review was to give a critical appraisal of HE as summary measure of population health and discuss the convenience of using it to study inequalities in health and mortality. Two considerations are presented with this matter. First, one of the features in the computation of HE is that analyses are driven by and constrained to the availability of mortality rates or life tables for the specific groups. This has led to the study of inequalities among certain groups only. Hence we found that papers concentrated on investigating inequalities in HE by gender and SEP. However, how gender and SEP may influence HE is still controversial. Some hypotheses have been advanced to explain gender inequalities, for example explaining sex differences as a consequence of the differences in the prevalence of fatal and non-fatal diseases among men and women, and partly ascribing the existence of the ‘gender paradox’ to inequalities in socioeconomic characteristics between men and women. On the other hand, the causes of SEP-based disparities are still unclear. One of the possible mechanisms explaining this association are health behaviors; but not many researchers have been able to study their role among older populations and if they did so, have focused only on some risk factors, such as smoking and overweight, whilst other behaviors such as physical activity and diet have remained almost unexplored. The second consideration –also mentioned in the introduction, before the current state of affairs in literature was presented—pertains to the complexity of the concept of health and disability and the difficulty of measuring it. The findings of this review confirmed the limitations in comparing different studies because of the variety of health indicators used to measure HE, the different estimation methods and the multiplicity of definitions for HE. There is not agreement in the way of defining and conceiving HE and there is not a preferred interpretation either. Furthermore, currently there not seems to be efforts put in place to address this problem.A final aspect that emerged from this systematic search pertains to the way in which institutionalized population has been considered across various studies. Institutionalized individuals represent an important component of older populations. Data used to estimate HE are mainly drawn from surveys that usually do not include these individuals. Some researchers combined different sources of data to cover the whole  population,106,120,The empirical evidence for the joint progress of morbidity and mortality are weak and scarce; and results are contradictory –9. The eS1 Table(XLSX)Click here for additional data file.S2 Table(DOC)Click here for additional data file.S3 Table(XLSX)Click here for additional data file.


We developed the Apollo Structured Vocabulary (Apollo-SV)—an OWL2 ontology of phenomena in infectious disease epidemiology and population biology—as part of a project whose goal is to increase the use of epidemic simulators in public health practice. Apollo-SV defines a terminology for use in simulator configuration. Apollo-SV is the product of an ontological analysis of the domain of infectious disease epidemiology, with particular attention to the inputs and outputs of nine simulators.infectious disease scenario, which is a representation of an ecosystem at simulator time zero that has at least one infection process (a class) affecting at least one population . Other important classes represent ecosystem elements , ecosystem processes , censuses of ecosystem elements , and infectious disease control measures.Apollo-SV contains 802 classes for representing the inputs and outputs of simulators, of which approximately half are new and half are imported from existing ontologies. The most important Apollo-SV class for users of simulators is In the larger project, which created an end-user application that can send the same infectious disease scenario to multiple simulators, Apollo-SV serves as the controlled terminology and strongly influences the design of the message syntax used to represent an infectious disease scenario. As we added simulators for different pathogens , the core classes of Apollo-SV have remained stable, suggesting that our conceptualization of the information required by simulators is sound.Despite adhering to the OBO Foundry principle of orthogonality, we could not reuse Infectious Disease Ontology classes as the basis for infectious disease scenarios. We thus defined new classes in Apollo-SV for host, pathogen, infection, infectious disease, colonization, and infection acquisition. Unlike IDO, our ontological analysis extended to existing mathematical models of key biological phenomena studied by infectious disease epidemiology and population biology.http://purl.obolibrary.org/obo/apollo_sv.owl.Our ontological analysis as expressed in Apollo-SV was instrumental in developing a simulator-independent representation of infectious disease scenarios that can be run on multiple epidemic simulators. Our experience suggests the importance of extending ontological analysis of a domain to include existing mathematical models of the phenomena studied by the domain. Apollo-SV is freely available at:  The simulators require information about pathogens, host populations, rates of infection transmission, interventions, and the disease outcomes of infections  as the host (the organism corresponding to the extended organism) through transmission of a member or offspring of a member of the infectious agent population.We found that IDO defines host role and infectious agent role require a process to realize them. This process would presumably be infection.Given that epidemic simulators and the relevant basic sciences on which they are founded recognize infection as a process, we needed to create a new class in Apollo-SV to represent it. The lack of a representation of the process of infection in IDO is surprising because IDO’s definitions of its classes A reproduction of a pathogen of a particular biological taxon inside or on the surface  of a host organism of another taxon, without invasion of any tissues of the host. We required this class to represent the input of the Regional Healthcare Ecosystem Analyst .As with other key terms, IDO lacked an adequate class and definition for the process of infection acquisition. IDO imports Beginning with the second definition (which for some reason the Transmission Ontology labels as a “suggested definition”), it erroneously restricts transmission to occur only between two hosts of the same species. It is thus not usable in infectious disease epidemiology or any other science that studies cross-species transmission, which frequently occurs in zoonoses and diseases like foot and mouth disease.transmission process in terms of a pathogen being transmitted, with no definition of transmitted. The definition also excludes infection acquisitions from contaminated objects and self colonization and refers to the undefined terms natural reservoir and source.The first definition has two major problems. The first problem is circularity, defining The second problem is an ontological one. It attributes to one process the property of being the means by which something else happens. For example, assume droplet spread of infection from one host to another by a sneeze. This definition equates the sneeze with the transmission process. That is, it says that only the sneeze exists, but it also has the property of “having transmitted the pathogen”. However, equating the sneeze to the transmission process is nonsensical because for example, droplets can remain airborne and infectious for hours. Thus the pathogen may not reach (or be transmitted to) another host until long after the sneeze is over. The sneeze cannot therefore be the transmission process. In reality, there are two distinct processes: the sneeze and the subsequent acquisition of an infection by the second host.We created a capability to configure six simulators: using the SEUA, an end user creates an infectious disease scenario that conforms to the XSD and then submits it to the simulators via Web services. The SEUA then retrieves the output of the simulators and displays it on maps and graphs. This capability was the end product of iterative, concurrent development of Apollo-SV and the XSD according to our analysis of the simulators, which included feedback from implementation in the Web services and SEUA. In addition, the SEUA displays textual definitions of Apollo-SV classes to the end user. Feedback on these definitions was fed back into ontology development which resulted in ontology changes including improved definitions. We are piloting a 7th simulator whose unique ontological commitments are reflected in Apollo-SV and the XSD, but are still undergoing refinement. The six configurable simulators are (1) a compartmental model developed by authors MMW, NEM, and JDL (disease agnostic); (2) the FRED model developed by the University of Pittsburgh Public Health Dynamics Laboratory in collaboration with the Pittsburgh Supercomputing Center Public Health Applications group and the School of Computer Science at Carnegie Mellon University (influenza A in humans); (3) the FluTE model developed by the University of Washington and Fred Hutchinson Cancer Research Center in Seattle (influenza A in humans), (4) a compartmental model of anthrax developed by authors MMW, NEM, and JDL, (5) the Computational Arthopod Agents (CLARA) dengue model developed by the Pittsburgh Supercomputing Center Public Health Applications group , and (6)We developed and implemented a common representation for simulator configuration and output and used it in an application that constructs and sends infectious disease scenarios to six different epidemic simulators. Our success in representing the inputs of a diverse sample of simulators lends support to our hypothesis that a common representation is feasible. Early usage of the ontology and exposure of its definitions to subject matter experts in software resulted in ontology improvements, most notably in the definitions of the core classes of Apollo-SV that we discussed here. This result is consistent with those of other ontology development efforts.The ontological analysis we used to create the common representation identified abstractions that spanned simulators diverse in their core mathematical foundations , pathogens, routes of transmission, geographical scope (single city or county vs. entire world), and interventions. The key abstractions were that the input of a simulator was an infectious disease scenario and that the scenario was properly understood as a representation of an ecosystem at a particular time, which corresponded to simulator time zero. We note that there is nothing specific to infectious disease in this conceptualization, which suggests that the ontology could be applied to simulation of other ecological phenomena.A novel aspect of our method was its focus on the ontological analysis of epidemic simulators. This focus quickly brought into view the key biological phenomena being simulated and their fundamental nature. Additionally, simulators—being mathematical models—make explicit ontological commitments about the core entities involved in infections and their acquisition, which led us to confront the issues involved in representing them from the outset. It is worth noting that simulators used in epidemiology are often rigorously vetted through peer review of simulator-based research, as well as peer review of the simulators themselves. A final advantage of our focus on simulators is that they make a relatively small number of ontological commitments, which allowed us to devote sufficient time to them, while still being able to implement an application that continously tested whether the evolving representation could configure an expanding set of simulators. We expect that ontological analysis of any domain for which mathematical models exist would benefit from a focus on the models. For example, for human physiology there is an extensive library of mathematical models that are the focus of the Human Physiome project .Prior work on the use of ontologies for modeling and simulation identified a distinction between so-called “referential” and “methodological” ontologies . The forWe were surprised that we were unable to reuse classes from IDO for infection, pathogen, host, colonization, infectious disease, and transmission process. We conjecture that IDO’s ontological analysis may have begun with a disease focus and worked from there to the nature of infection, whereas we began with a biological science perspective. Our focus differed fundamentally from IDO’s concentration on how the terms are used in clinical medicine. In particular, our focus led us to a requirement to represent the process of infection, including key parts of this process such as the infectious period, as opposed to the steady-state, material-entity view of IDO.infection, pathogen, host, and infectious disease do not conflict with how these phenomena are understood by clinical medicine and thus could be reused without difficulty by ontologies that support clinical applications. In fact, in the case of zoonoses and infections that result from a prior process of colonization, our representations are a marked improvement because our definition of infection acquisition permits cross-species transmission and infections resulting from self colonization, whereas IDO’s definition of transmission process does not. Also, our definition of host and pathogen are more consistent with their usage by infectious disease specialists.We note however that our definitions of infection as a material entity. It erroneously defines infection acquisition as occuring only in humans and does not axiomatize its classes. Okhmatovskaia et al. do not define for SimPHO [2We also could not reuse other prior work on ontologies that have overlap with Apollo-SV. This work includes the Epidemiology Ontology (EO)  and the r SimPHO  any of tGiven that simulator configurations require representing several kinds of knowledge including probabilistic and mathematical knowledge, it was not possible to use an OWL2 representation in the Web services to configure simulators. At present the application that creates infectious disease scenarios does not invoke any description-logic reasoning supported by the axioms in Apollo-SV. Nevertheless, we found it advantageous to create the OWL2 representation and reuse it at the lower level of information representation of XSD. However, in other work, our OWL2 representation  supports reasoning in our ontology-based catalog of infectious disease epidemiology (OBC.ide), which is a catalog of datasets, publications, grey literature, and simulators . The OBCOur future plans include expanding Apollo-SV and the XSD to cover additional simulators and types of information used in infectious disease epidemiology.Apollo-SV captures the output of our ontological analysis of the entities in reality represented by epidemic simulator configuration and output. It also supplies the standardized terminology used in epidemic simulator configuration and output, which also includes an XSD-based syntax and database schema. We validated Apollo-SV through use in a simple end-user application that enables analysts to specify an infectious disease scenario and submit it to one or more of six simulators. Our analysis of biologically-grounded epidemic simulators and our process of testing the ontology in software led to scientifically accurate definitions that we have found to be reusable across diverse simulators to date. When available, mathematical models of natural phenomena like epidemics are potentially useful starting points for ontology development.