At present there are possibility and necessity of simulating any medical information statistical systems that makes it possible to save financial and time resources, to avoid serious errors in designing, to determine trends and means of updating. It is a question not of the possibility of simulation but of its necessity which is an integral link of medical information statistical systems development cycle.

В настоящее время имеется возможность и необходимость моделирования любых медицинских информационно - статистических систем, что позволит сберечь финансовые, временные ресурсы, избежать серьезных ошибок проектирования, правильно определить направления и способы модернизации. Следует говорить не о возможности моделирования, а об обязательности проведения данного этапа, как неотъемлемого звена цикла разработки медицинских информационно-статистических систем.

The efficiency of created medical information statistical systems (MISS) to a great extent is dependent on the quality of predesigned examination and designing. MISS should be continuously improved and updated while adapting to new conditions, medical technologies, tasks etc.

Substantiation of hardware structure, choice of software, network standards require consideration of a great number of parameters. As a rule, development engineers are unable to perform real physical simulation of information system, which they create, and have to confine themselves only to their own experience (expert judgements) or simulate separate fragments of a future system. In the last few years the worth of decision error has considerably increased, a choice of elements and system construction versions has become wider and complicated.

The situation can be settled to a certain extent with using current software of computer simulation. A variety of such program parts are known now, but their use in Russia is hampered due to their high cost and the absence of localized versions. At the same time numerous theoretical studies concerning MISS have enabled specialists to be well-informed in the laws of public health system operation, have helped them to determine main requirements for simulation objects. The many – times increased calculation efficiency of widely used PC can serve as a weighty argument for using simulation systems.

Inclusion of simulation into MISS development and updating makes it possible to avoid decision error, to design a balanced system capable of advancing. This is possible owing to checking against a model the technical decision versions, detecting bottlenecks, and improving the project before its realization. A set of iterations against the created model will be less expensive than investments into erroneous project. Besides, economy of the time during which an operating MISS can be efficiently and reliably realized is great, and maximal conformity of the system with customer’s requirements becomes possible.

Thus, it is a question not of the possibility of simulation but of its necessity which is an integral link of MISS development cycle.

Successful work of any modern public health establishment is greatly dependent on its information system.

Main requirements for information system are the following:

• adequacy (coincidence with tasks);
• scaling capability (maintenance of adequacy with organizational structure development and information load increase, without considerable change in system architecture);
• widening capability (advance possibility);
• reliability;
• investments safety;
• economic efficiency (excess of profit over expenses);
• safety.

These requirements are met as a result of the following stages realization: customer’s demands, developer’s design, designing process, implementation and service activities, analysis, updating.

The use of simulation technologies allows for decreasing iterations of these cycles and reducing total expenditures connected with information system design and updating.

Thus, computer simulation makes it possible to realize in dynamic regime the following scheme: ”information system developer` design -> model -> verification -> realization without errors” or “existing state of information system -> model -> optimal state of information system”.

The purpose of simulation programs consists in detailed modeling of sophisticated information systems, speedy estimation of efficiency, and prediction of state after various exposures or updating. It is evident that simulation of complicated systems consists in decomposition to the level conditioned by tasks. Hierarchical representation of complicated information systems as a set of connected subsystems forms a basis for model construction. The subsystems obtained as a result of such decomposition can be in their turn subdivided into subsystems of the next hierarchic level, and so on endlessly. One simply must stop at the proper time.

Excessive decomposition can lead to an opposite result, and instead of simplification of simulated system we shall come to its complication. Usually two main types of decomposition are considered: algorithmic type, which subdivides the system according to the processes occurring in it, and object-oriented type capable of dividing the system into the abstraction classes of the same kind.

Construction of information system models can be represented as standard succession of the following steps:

• description of information system topology and determination of equipment parameters;
• description of traffic sources and their behavior, description of network loading;
• determination of simulation scenario;

Determination of information system topology and connections of traffic sources with topology nodes is considered to be an ideal field for object-oriented decomposition. For description of traffic sources and changes in network time loading the algorithmic decomposition is required. A great number of program products are available for simulating various systems. Some of them allow for using both types of information system decomposition. By a good abstraction is meant one, which permits us to emphasize the details important for consideration and usage, and to give up the details inessential at the given moment or distracting attention.

On the basis of the foregoing it is evident that at present there are possibility and necessity of simulating any MISS that makes it possible to save financial and time resources, to avoid serious errors in designing, to determine trends and means of updating.