A PRACTICAL EXPERIENCE WITH NDT

The System to Measure the Grade of Handicap

M. J. Escalona, D. Villadiego, J. J. Gutiérrez, J. Torres, M. Mejías

Department of Computer Languages and Systems. University of Seville. Seville, Spain.

Keywords: Web Engineering, Practical Experiences.

Abstract: The necessity of applying technological advances in the medicine environment is an unquestionable fact. In

the last years, important applications of new technologies in medical systems to help doctors or to make

easier the evaluation, the treatment or, even, the relation between the doctor and the patient have been

presented. However, there is sometimes an important gap in the development of these new systems. The

specific and complex features of the medical environment often complicate the communication between

doctors, when they require a new system, and experts in computer science. This work introduces a

methodological proposal to specify and analyze software systems. Its main goal is to make easier the

communication between final users and customers and the development team. The report presents our own

practical experience by the application of this methodology in a real system to measure the grade of

handicap in patients following laws in Spain.

1 INTRODUCTION

The application of Computer Science and

technological advances in any area is always a step

forward in the evolution of this area. In the medical

environment, this evolution is really important

because it is oriented to improve the treatment of the

patient.

However, when systems are very complex or

specific in their vocabulary, in its requirements or

even in its objectives, the communication between

experts in Computer Science and experts in the

system makes the project very difficult and

expensive (Sommerville, 2002) (Pressman, 2002).

Most systems developed in the medicine

environment present this problem.

In the department of Computer Languages and

Systems of the University of Seville, a new

methodology named NDT (Navigational

Development Techniques)(Escalona, 2004) has been

developed. This methodology works in the first

phases of the life cycle of a software project:

requirements and analysis, and its main objective is

to make easier the communication between users,

customers and the development team.

NDT has been applied in several real environments

and several real projects that are being used

nowadays(Escalona, 2004). However, a medical

project was a great opportunity to validate our

methodology. In this work, we present an abstract

about the application of NDT in the development of

a system to measure the grade of handicap following

Spanish laws.

The report starts, in section 2, with a description of

the problem to solve in the project. In section 3, a

global vision of NDT is presented and section 4

reports the final obtained system and the application

of NDT in its development. Finally, in section 5,

conclusions, future works and final evaluation are

presented.

2 THE PROBLEM TO SOLVE

In the Royal Decree 1971/1999 (23/12) the Ministry

of Social Issues in Spain defined how to evaluate the

grade of handicap of a patient in order to get a level

of handicap. This level of handicap is essential for

an patient because, depending on this grade, he/she

gets subsidies, helps or special cares in Spain.

However, the application of this Royal Decree is

not easy. To grade the handicap grade of a patient,

doctors not only have to assess the handicap itself,

but also its consequences for the patient. For

instance, a patient who cannot walk can also have

psychological problems as a result of his/her

physical problem.

212

J. Escalona M., Villadiego D., J. Gutiérrez J., Torres J. and Mejías M. (2006).

A PRACTICAL EXPERIENCE WITH NDT - The System to Measure the Grade of Handicap.

In Proceedings of the Eighth International Conference on Enterprise Information Systems - ISAS, pages 212-217

DOI: 10.5220/0002442502120217

 SciTePress

In this sense, the Alcer Foundation (Alcer, 2005)

suggested to the Madeira group, at the University of

Seville, to develop a system that facilitates the

handicap grading process for doctors and patients. In

September 2003, Madeira group and Alcer

Foundation started to develop a new web system.

The development of this system was not easy for

several reasons:

The system was very new. There was no previous

experience in that, so the development environment

was very difficult for the development team.

The terminology of the system was very complex

and close to the medical environment. This was a

problem for the computer science ones because they

did not have specific formation in this area.

For all these reasons, the working environment

could be defined as a very complex one for the team.

Techniques to specify, analyse or design the system

must be suitable for users and customers and also for

the development team.

3 INTRODUCING NDT

NDT is a methodological proposal to specify and

analyse requirements in web systems. This proposal

is focused on two main aspects (Escalona et al.,

2003)(Escalona et al., 2004)

The first one is that web systems have special and

critical characteristics. It is why in web

development, these special characteristics have to be

dealt with special methods and techniques suitable

for them (Barry & Lang, 2001) (Retschitzegger &

Schwinger, 2000) (Escalona & Koch, 2004).

The second point is that in web system, it is

usually necessary a good communication between

final clients, the experts in the system subject and

the development team because only the users know

how the system must be.

NDT is a methodological process in the web

environment that it is focused on the requirements

and analysis phases. It offers a systematic way to

deal with the special characteristic of the web

environment. NDT is based on the definition of

formal metamodels, presented in (Escalona, 2004),

that allow to create derivation relations between

models. NDT takes this theoretic base and enriches

it with the necessary elements to define a

methodology: techniques, models, methodological

steps, etc. in order to offer a suitable context to be

applied in real projects.

In this sense, NDT starts with the theoretic

definition of the requirements engineering

metamodels and proposes a methodological

environment to drive the team in the capture,

definition and validation of requirements following

the next ideas:

1- In the elicitation of requirements NDT

assumes its own techniques inherited from

the requirements engineering environment

like interviews, brainstorming or the study

of the previous systems (Duran, 2000).

2- In order to describe requirements, NDT

uses some standard models, like the use

cases, and patterns. A pattern is a special

template with predefined fields that must to

be completed between the development

team and final users (Escalona, 2004).

3- In the validation of requirements, NDT also

proposes a group of techniques like the

traceability matrix (Duran, 2000) or the

fuzzy thesaurus (Mirbel, 1995) adapted to

NDT patterns in order to propose a more

agile requirements validation (Escalona &

Cavarero, 2005).

NDT also normalizes the structure of the results

that must be developed during the requirements

engineering and it proposes which are the complete

structure of the document.

With the theoretic base of metamodels and

relations, the next phase is the analysis one. In the

analysis phase three models are generated:

1- The conceptual model, that defines the

static structure of the information and its

relations.

2- The navigational model, that defines how

users can navigate through the information.

3- The abstract interface model is composed

by a group of HTML and XML prototypes

that let validate the conceptual and

navigational models.

However, the generation of these three models is

made in two phases. In the first one, analysis models

are generated systematically from the requirements

using the theoretic relations defined between

models. In this sense, NDT can be defined as a

model driven proposal. These models are named

basic analysis models.

In these basic models, analysts can make some

changes in order to make more suitable these

models, getting the final analysis models. The

construction of these final models is not systematic

and they depend on the experience of the analyst.

NDT offers some guides and processes in order to

make easier the analyst’s revision.

Besides, NDT controls that the changes proposed

by the analyst are agree with the definition of

requirements. In this sense, NDT manages that the

final analyst models and the requirements definition

A PRACTICAL EXPERIENCE WITH NDT - The System to Measure the Grade of Handicap

213

are consistence. In figure 1, the NDT life cycle is

presented with an activity diagram.

Final models generated in NDT are compatible

with other proposals like UWE (Koch, 2001) or

OOHDM (Rossi, 1996). For this reason, from them,

the development team can continue the life cycle

with these other proposals that have been widely

accepted by the research community.

In conclusion, NDT can be define as a

methodology to the requirements and analysis

phases, the rest of the life cycle is dealt with other

important proposals, thus it is not necessary to work

more on them, like it is shown in the comparatives

studies. NDT is offered to cover a gap in the

treatment of the life phases in the Web Engineering

(Desphande et al., 2002).

Finally, it is important to stick out that NDT has an

associated tool, named NDT-Tool (Escalona et al.,

2003) that supports all the life cycle of NDT. This

tool lets automate all the systematic processes of

NDT, apply all its techniques and get the results

automatically.

4 THE FINAL SYSTEM

The development of the system to measure the grade

of handicap was an mportant test for NDT. The

development environment was very difficult: the law

was very new, there was no any previous system to

apply it, the terminology of the users (medicine,

illness, etc) was really difficult for the development

team, etc. In conclusion, a great real experience to

prove if NDT really ensures communications with

the user.

The essential idea of the system is shown in figure

The handicapped patient, once finished the

treatment and following the indications of his/her

family doctor, visits various specialists who has to

value his different health problems (physical and/or

psychological) derived from his illness. This

communication is represented in figure 2, steps 1

and 2. Specialist can advise the visit to another

specialist who values another aspect of his/her

handicap. Each specialist completes his/her own

evaluation. Each partial evaluation is stored in the

system, which is offered through Internet. This is

represented in figure 2, in step 3.

When the process of evaluation is finished the final

evaluation report is automatically generated by the

system. It can be generated by the patient’s family

doctor or by any specialist. This final report, which

is structured following the Royal Decree rules, is

presented by the user to the Spanish Government

who defines the grade of handicap and calculates the

compensations, payments or subsidies for the

patient.

The interface was an important aspect of the

system. The law covers various systems, physical

aspects so as psychical, and includes a great

complexity. Each specialist only must access to the

matter that is called on to him/her to evaluate, but,

also, he/she

must be able to access to consult other evaluations

made by other specialists of an agile way.

In order to present all the information, the system

is structured like a tree. Each leaf of the tree

represents the possible damage of a subsystem of the

patient: the skeleton-muscular system, the nervous

system, etc. In figure 3 an example of the digestive

system is presented (

The system is developed in Spanish, for

that reason the screen is in Spanish)

In each lead, the specialist found each piece of

information that have to be valued for each patient

according to the Royal Decree. The tree is always on

the left side and, when a concrete lead is selected all

the information about this concept is presented on

the right side.

Figure 1: NDT Development Process.

Deal with requirements

Capture

Define

Validate

correct?

Capture

Define

Validate

correct?

yes

Analyse

Generate basic

models

Generate

final models

Generate basic

models

Generate

final models

inconsistent?

yes

Figure 2: Schema of the system behaviour.

ICEIS 2006 - INFORMATION SYSTEMS ANALYSIS AND SPECIFICATION

214

This form of interaction with system is very

comfortable and intuitive for the doctor. The tree

displays all the information covered by the law but

in a structured way according to the different body

systems. All the details and casuistries indicated in

the law, as well as the restrictions to follow by the

doctors are controlled by the system, not allowing

inconstancies or errors. In addition, as the tree

appears as the Windows Explorer turns out very

intuitive to use by the doctors.

The final result has had a great acceptance, but it

would not have been possible to arrive at it without a

methodological initial study of the system. In this

point, the NDT use has been fundamental. NDT

patterns have been a great technique of

communication that has made more fluid the

enclosed work between the users and the

development team.

Once the objectives were defined, the information

storage requirements or, what is the same, the

information that had to cover the system according

to the law, began to be defined. These data were

presented in patterns similar to the one presented in

table 1.

Specific data describe each concrete piece of

information that must be stored for each patient. For

each piece of specific data its name, a short

description about its meaning and its nature that

describes the structure of this piece must be defined.

There are some classical natures like string or

integer, but there are also some advanced natures.

For instance, in the field “actual treatment” the

nature is RA-02. This means that the structure of this

piece of data is described by requirements RA-02,

another storage requirement, which is also defined in

the system.

When the group of storage requirements was

defined, the next step was to set up the different

roles of users that could interact with the system. In

this point, only two actors were defined: the doctor

and the administrator. The first one could only

manage users’ information. When a new doctor

wants to use the system, he/she has to ask for

permission to the administration. The second one,

the doctor, could access to any information of the

system. Nevertheless, it was important to find some

structured form to show all the information.

The next step was to study the functionality of the

system. The system did not have a very complex

functionality. Basically:

¾ To manage information about patient and

his/her evaluation and treatment.

¾ To generate the final report following the

restriction of the law.

The most critical aspect of the system was to

establish a good navigational structure that allowed

to access to the information in an easy way. In this

point, the study of the interaction requirements was

fundamental.

With the definition of the interaction requirements

patterns, the development team and the users

decided to structure the information in the different

Figure 3: A screen of the system.

A PRACTICAL EXPERIENCE WITH NDT - The System to Measure the Grade of Handicap

215

organic system presented in each lead of the tree

shown in figure 2 (Muscle-Skeleton, nervous

central, cardiovascular, peripheral-vascular,

respiratory, digestive, and others).

In the last step, some other requirements like the

necessity of security in the treatment of the

information were defined.

The complete application of the NDT to this

system, all patterns and diagrams can be found in

(Villadiego et al., 2004). Nevertheless, observing the

pattern of table 1 some conclusions can obviously be

obtained.

Table 1: An example of pattern in NDT.

RA-01 Patient’s information

Description This pattern describes what information must be

stored for each patient in the system. Concretely:

Name and description Nature

Name: It stores patient’s name. String

DNI: It stores patient’s number of

identity national document..

Integer

NSS: It stores patient’s number of the

Social Security.

Integer

Born Data: It stores patient’s born

data.

Date

Phone number: it stores patient’s

phone number.

Integer

Weigh: It stores patient’s weigh. Integer

Height: It stores patient’s height. Integer

Actual treatment: It stores all the

information about the actual treatment

of the patient.

RA-02

Specific

Data

Specialists’ evaluation: It stores all

the information about the validation of

the grade of handicap made by

specialists.

RA-03

Although each pattern for each requirement is

different and here it was only presented the storage

information requirements one, everyone follows the

same structure and all of them look for collecting the

necessary information in the simplest way.

For that reason, the patterns are easy to understand

by the end user, in this case the doctors. The

terminology used in the fields and the descriptions

has been completed according to the argot of the

system.

But the patterns are also extremely useful for the

development team that finds in them a structured

definition of the requirements

This structured definition is very important in the

following phases of the life cycle. In fact, NDT

proposes systematic processes to go from the

patterns to the analysis models.

In this system, with NDT-Tool, a conceptual class

diagram, a navigational class diagram and the

prototypes of the system were derived automatically

from the set of patterns.

The automatic attainment of results trimmed the

time of development and, therefore, the cost of the

project. In addition, the prototypes resulted helpful

to validate the results with the user.

While the definition of requirements was made

with the user and validated by this one already from

first phases of the life cycle, the rest of the process,

design and implementation, was a pure task of the

development team. This one was fundamentally

based on the structured definition of requirements.

In general, although the work in the requirements

engineering supposed a concerted effort for the

team, it was compensated by the reduction in price

and the quality of the results in the later phases.

5 CONCLUSIONS AND FUTURE

WORKS

This paper presented a real and a practical

experience with our methodology, NDT. This

application has been very important in this project in

several aspects. The first one is to value if NDT and

its techniques and models were efficient to deal with

complex development environment. We have got

very good results in that. Patterns offer a good way

of communication with the users and make easier

the work between users and the development team.

By other way, the automatic generation of models

in the analysis of NDT makes shorter the

development time. To get automatically some

prototypes of the system is a good technique to

evaluate requirements with users. The disadvantage

we have to stick out is that the maintenance of

patterns can be sometimes very complex and

expensive for the system. For this reason, we

concluded that, mainly in complex projects, it is

necessary the use of NDT-Tool to manage patterns.

As a contribution for the medical environment, the

final system has resulted in a complete success. It is

being used by a lot of specialist in Andalusia (in the

south of Spain) and it is being adapted to be

accepted in all the country.

As a future work we are thinking to apply some

statistical and data mining techniques, obviously

keeping the patient’s anonymity. Thanks to these

techniques, we hope to find relations between

illnesses. For instance, to establish rules like “if a

patient has lost his leg and he/she has not worked for

several years, he/she will probably have some

psychological problems”.

ICEIS 2006 - INFORMATION SYSTEMS ANALYSIS AND SPECIFICATION

216

It could be a good guide for the family doctor or

specialists to get the most suitable and complete

evaluation for the patient.

As final conclusion two ideas can be stuck out.

The first one is the importance to keep a good

communication between researchers in computer

science and medicine. The computer science

community has to validate its approach in real

projects to sure the value of its results. Also,

medicine community must incorporate, as much as it

is possible, the technological advances in its works

to obtain the best results. The second main idea is

that the team work between these research areas can

get good projects and results that help patients and

their families and make easier the application of

treatment, the granting of helps and, in general, the

dealing of their health problems.

REFERENCES

Federación Andaluza Alcer (Asociación para la Lucha

Contra las Enfermedades del Riñón). www.alcer.info

Barry, C., Lang, M. A Survey of Multimedia and Web

Development Techniques and Methodology Usage.

IEEE Multimedia. 2001.

Ceri, S. Fraternali, P., Bongio, A., Brambilla M., Comai

S., Matera M. Designing Data-Intensive Web

Applications.Morgan Kaufman. 2003

Deshpande, Y., Marugesan, S., Ginige,A., Hanse,S.,

Schawabe,D., Gaedke, M, B. White. Web

Engineering. Journal of Web Engineering. Vol. 1 Nº 1.

pp. 3-17. Rinton Press. 2002.

Durán A. Un Entorno Metodológico de Ingeniería de

Requisitos para Sistemas de Información. Ph. Thesis.

Dep. de Lenguajes y Sistemas Informáticos. Uni. de

Sevilla. 2000.

Escalona, M.J. Modelos y técnicas para la especificación y

el análisis de la navegación en sistemas software. Ph.

European Thesis. Depart. of Computer Languages and

Systems. University of Seville. October 2004.

Escalona, M.J, Mejías M, Torres J, Reina A.M. The NDT

Development Process. Proceedings of IV International

Conferences on Web Engineering. LNCS 2722. pp.

463-467. Springer Verlag 2003

Escalona, M.J, Mejías M, Torres J, Reina A.M. NDT-

Tool: A tool case to deal with requirements in web

information systems. Proceedings of IV International

Conferences on Web Engineering. LNCS 2722. pp.

212-213. Springer Verlag 2003

Escalona, M.J., Mejías, M., Torres, J. Developing systems

with NDT & NDT-Tool. 13th International

Conference on Information Systems Development:

Methods and Tools, Theory and Practice. Lithuania.

September 2004

Escalona, M.J., Koch, N. Requirements Engineering for

Web Applications: A Comparative Study. Journal on

Web Engineering, Rinton Press, 2004, Vol2. Nº3. pp

193-212.

Escalona, M.J., Cavarero, J.L. Building Class Diagrams

Systematically. 13th International Conference on

Information Systems Development: Methods and

Tools, Theory and Practice. pp. 378-381. Karlstat,

Sweden. August, 2005.

Koch, N. Software Engineering for Adaptive Hypermedia

Applications. Ph. Thesis, FAST Reihe Softwaretechnik

Vol(12), Germany 2001

Mirbel, I. A fuzzy thesaurus for semantic integration of

schemes. International workshop on engineering

design : AI system for conceptual design, Ambleside,

England, March 1995.

Pressman, R.S. Ingeniería del Software. Un enfoque

práctico. Mc Graw Hill, 2002

Retschitzegger, W. & Schwinger, W. Towards Modeling

of Data Web Applications - A Requirement´s

Perspective. Proceedings of the American Conference

on Informatin Systems AMCIS 2000, Vol 1, 149-155.

Rossi, G. An Object Oriented Method for Designing

Hipermedia Applications. PHD Thesis, Departamento

de Informática, PUC-Rio, Brazil, 1996

Sommerville, I. Software Engineering.

Addisson Wesley,

2002.

Villadiego, D., Escalona, M.J., Torres, J., Mejías, M.

Aplicación de NDT al sistema para el reconocimiento,

declaración y calificación del grado de minusvalía.

Report interno LSI-2004-02. Departamento de

Lenguajes y Sistemas Informáticos. Universidad de

Sevilla. June 2004.

A PRACTICAL EXPERIENCE WITH NDT - The System to Measure the Grade of Handicap

217