José M. Marqués

Impact of Selective Financing of Drugs on Pharmaceutical Expenditure Control in the Province of Valladolid, Spain

SummaryIn July 1993, public financing for 1692 drug specialities was stopped in Spain (a drug speciality is a medicine with a defined composition, particular pharmaceutical form and dosage, prepared for immediate use, ready and packaged for dispatching to the public, with uniform name, packaging and labelling which has been granted authorisation by the State Administration and registered in the Pharmaceutical Specialities Register). We designed a study to assess the repercussions of this so-called ‘selective financing’ on expenditure contral. The aims of the study were 2-fold: first, to forecast the consumption of drug specialities that are reimbursable on the Spanish National Health Service, had selective financing not been applied; and, secondly, to estimate the impact of selective financing on drug consumption.For short- and medium-term forecast estimates, time-series analysis was used, and was applied to monthly consumption data. The measures of consumption used were the number of prescriptions per 1000 patients, and cost [in Spanish pesetas (Pta;

A user requirements elicitation tool

US1 = Pta123.9, February 1996)] per 1000 patients. Data were analysed from January 1986 up to the introduction of selective financing.We found that drug specialities excluded by selective financing showed, overall, a negative increase (i.e. the consumption of drugs that were excluded under selective financing decreased). The repercussion forecast, both in terms of prescription numbers and cost, of the 13 excluded drug specialities that had the highest pre-selective financing consumption is decreasing compared with total consumption. The assessment of the repercussions of selective financing up to December 1994 was made by calculating the difference between actual expenditures and forecast expenditures in the absence of selective financing. This repercussion, in prescriptions, was lower than the percentage of the 1692 excluded drug specialities relating to total consumption in 1992. The repercussion in cost, nevertheless, was greater than expected during the first year of selective financing application. This could be attributable to average price containment of drug specialities due to causes other than selective financing itself. The economic impact of selective financing after 1 year of application was reduced because of accommodation phenomena.

Feature Diagrams and their Transformations: An Extensible Meta-model

Use cases are nowadays the favoured technique for defining the functional requirements of a software system. Their use implies that most of the desired functionality of the new system is well known. The aim of this work is a methodological proposal (and a tool to support it) to accurately define this functionality, starting from the way the end users currently do their work. This method and tool are independent of the development paradigm and could generate useful results for the most frequently used CASE tools with the addition of the appropriate translators.

On the Multiplicity Semantics of the Extend Relationship in Use Case Models

Feature models represent the variability and commonality of software product lines and permit the configuration of each specific application to be selected. We use a hypergraph based formalism to define an extensible and comprehensive feature meta-model. As a result, we readily can build a set of modeling tools compatible with the different flavors of these diagrams. Finally, automatic transformations of feature diagrams into UML models of the product line architecture are defined to register model traceability.

DocFlow: workflow based requirements elicitation

Use cases are a useful and simple technique to express the expected behavior of an information system in successful scenarios or in exceptional circumstances. The weakness of use cases has been always the vague semantics of the relationships, in particular the extend relationship. The main contribution of this article is an attempt to clarify the different interpretations that can be adopted. A major revision of the UML standard would be impractical, but the extension point concept could be completed, including minimum and maximum multiplicity attributes. Using these minor changes, the legal combination of base/extending use cases in the requirements models would be unequivocally defined. Therefore, the ambiguity of the original UML models would be removed.

Feature diagram formalization based on directed hypergraphs

Abstract Use cases are the favoured technique for defining the functional requirements of a software system, but their use implies that the desired functionality of the new system is well known. The aim of this work is to present an alternative technique—and a supporting tool—to accurately define this functionality, expressed as use cases, starting from the workflows that describe the end user work. The use of hypergraphs in the proposed algorithm of transformation reinforces the generation process. In addition, the technique is independent of the development paradigm and a variation in the algorithm allows obtaining Data Flow Diagrams.

Applying formal concepts analysis to the construction and evolution of domain frameworks

Feature models are used to represent the variability and commonality of software product lines (SPL), and to decide on the configuration of specific applications. Several variants based on tree or graph hierarchical structures have been proposed. These structures are completed with additional constraints, generally expressed in parallel with the feature diagram. This paper proposes the use of hypergraphs to integrate both concepts in a unique characterization. Therefore, the definition, validation and selection of feature configurations can be internally based on the hypergraph properties and well-known algorithms, while the concrete visual syntax remains unchanged for domain engineers. The implemented hypergraph algorithms have been tested using a complete set of feature diagrams. Finally a feature meta-model can be derived directly from the formal definitions, providing the foundations for building feature modeling tools.

Support to development-with-reuse in very small software developing companies

Framework development is a hard process. Hardness increases when dealing with domain frameworks, which should be quickly adapted to the changing requirements of the business areas they model. We show a development process especially designed for this kind of frameworks. Thanks to the formal support provided by some techniques, based on formal concepts analysis, and thanks to the set of tools that implement them, the process provide an automatic support for the construction of domain frameworks. Taking this process (of domain frameworks construction) as starting point, we propose the generalization of the employed techniques to support the whole framework life cycle. The different phases of the proposed process are analyzed with detail, making special emphasis in their automatic aspects. A tool in experimental phase is also described. Then, some results of using the tool for the analysis of a class library, are presented as case study.

Aided domain frameworks construction and evolution

There are a variety of specifications to represent information about reusable assets. Most of this models and specifications are complex, difficult to understand and implement in reduced environments. Small and very small organizations (less than 10 employees) can benefit from reuse but, they need easy to understand methodologies, processes and tools; low cost technologies and, flexible development models. We provide a flexible approach to the modelling process proposing an easy model to represent and classify reusable assets, mainly those developed inside the organization but, compliant with standards to allow the use of COTS. Our model deals with functional and non-functional properties and, its able to represent assets from the whole software development life cycle.

Obtaining generic classes automatically through a parameterization operator. A focus on constrained genericity

Framework development is a hard process. Hardness increases when dealing with domain frameworks, which should be quickly adapted to the changing requirements of the business areas they model. This paper is devoted to show a development process especially designed for this kind of frameworks. Thanks to the formal support provided by some techniques, based on Formal Concepts Analysis, and thanks to the set of tools that implement them, the process provide an automatic support for the construction of domain frameworks.Taking this process (of domain frameworks construction) as starting point, we propose the generalization of the employed techniques to support the whole framework life cycle. The different phases of the proposed process are analyzed with detail, making special emphasis in their automatic aspects. A tool in experimental phase is also described. Then, some results of using the tool for the analysis of a class library, are presented as case study.