INTEGRATING CASE-BASED REASONING WITH

EVIDENCE-BASED PRACTICE FOR DECISION SUPPORT

Expedito Carlos Lopes and Ulrich Schiel

Computing and Systems Department, Federal University of Campina Grande, Brazil

Keywords: Case-based reasoning, Evidence-based practice, Decision support.

Abstract: Evidence-Based Practice (EBP), an emergent paradigm, uses the premise that decision making can be based

on scientific proofs available in reliable data bases, usually found on sites over the Internet. However, the

procedures of the EBP do not provide mechanisms for retention of information and knowledge strategic of

the individual solutions, which could facilitate the learning of different end-users, in the future. On the other

hand, Case-Based Reasoning (CBR) uses the history of similar cases to support decision making. But, the

retrieval of cases may not be sufficient to give support to the solution of problems. Since both research

evidences as well as similar cases are important for decision-making, this paper proposes the integration of

the two paradigms for problem-solution support, regarding complex problems. An example of the justice

area is presented.

1 INTRODUCTION

Problem is the main element that triggers the process

of decision making. When it presents difficulties

associated with the absence of available solutions, or

even when it demands a great effort to understand

why it happens or which are its causes, it is

considered a complex problem (Loriggio, 2002).

In 1992, emerged the Evidence-Based Medicine

(EBM) that has its primary focus on provide

effective counseling to help patients with terminal or

chronic illness to make decision in order to cure of

illness, extend or increase the quality of their life

(Sacket et al., 2001).

Supported in the EBM, was standardized the

Evidence-Based Practice (EBP) that uses the

premise that decision making can be based on

scientific proofs available in reliable data bases,

usually found on sites over the Internet, derived

from primary studies (e.g. randomized clinical trials)

and/or secondary studies (systematic review and

meta analysis) carried out by independent research

groups (e.g. Cochrane Collaboration on medical

area, and Campbell Collaboration concerning crime

& justice and education areas). EBP on the medical

area involves complex and conscientious decision-

making, based not only on the available evidences

but also on patient characteristics, situations, and

preferences (Sackett et al., 2001). EBP has expanded

itself to the healthcare area in general.

Although with some alterations, this paradigm

presents itself in several different areas, such as

criminal justice, including politics for crime

prevention, considering the potential offensive risk

of the defendants (Warren, 2007).

On the other hand, Case-Based Reasoning

(CBR) uses the history of similar cases to support

decision making (Pal and Shiu, 2004), instead of

using research evidences. CBR fails when no similar

case can be found in the Case-Base. Moreover, the

retrieval of cases may be not sufficient to give

support to the solution of complex problems.

But, EBP procedures do not provide mechanisms

for retention of information and knowledge strategic

of the individual solutions, which could facilitate the

learning of different end-users, in the future, and

preserving evidences used, since they can be

modified or removed of the Internet later.

Since both research evidences and similar cases

are important for decision-making, the integration of

the two paradigms constitutes an interesting research

topic to the solution of complex problems. Thus,

complex cases and research evidences can be

expressed together in a knowledge representation

and the integration of EBP and CBR techniques is

considered as support for the development of

applications that encompass decision making.

368

Carlos Lopes E. and Schiel U. (2009).

INTEGRATING CASE-BASED REASONING WITH EVIDENCE-BASED PRACTICE FOR DECISION SUPPORT.

In Proceedings of the 11th International Conference on Enterprise Information Systems - Artiﬁcial Intelligence and Decision Support Systems, pages

368-371

DOI: 10.5220/0002007403680371

 SciTePress

Figure 1: Basic Cycle of Evidences and Cases Processing.

2 INTEGRATING EBP

PROCEDURES WITH CBR

FOR DECISION SUPPORT

In the EBP, according to Sackett (2001), what is

objectively searched is "the integration of best

evidence from research, clinical skill and preference

of the patient." Clinical knowledge and experience

are used to identify the health state and diagnosis of

patients, their individual risks and benefits of

proposed interventions. Moreover, the patients worth

about preferences regarding private, personal

concerns and expectations brought to the

appointment are considered in clinical decisions.

Systematically, the EBP includes the steps:

1. Transformation of the problem into a question to

be answered;

2. Identifying the best evidence to answer the raised

question;

3. Critical analysis of the evidence in order to

validate its applicability and its impact in relation

to the question;

4. Integrating clinical skills, values and cultural

aspects of the patient related to the previously

extracted procedures;

5. Evaluation of the efficiency and effectiveness in

the results of each step.

In crime prevention, the concept of EBP is defined

as: the correlations practice that has been proven

through scientific research aimed to reduce the

recidivism of offenders. In Warren (2007), EPB

principles used by judicial units in order to reduce

criminal recidivism are presented. EBP considers the

risk and needs principle of the offender, use of

risk/needs assessment instruments, integration of

treatment and community-based sanctions.

In CBR, the approach to get a solution for a

certain problem is based on a comparative analysis

of previous realities with a new similar reality. There

is an analogical reasoning process based on the

degree of similarity in form of deductive inference

(Pal and Shiu, 2004; Russel and Norvig, 2003).

CBR and EBP have common aspects such as (i)

use of procedures to support decision-making; (ii) be

based on a problem presented by a motivator agent;

(iii) use of search and similarity measures involving

the current situation and previously stored situations;

(iv) they presents the results in ranking schemes.

The two approaches can be considered

complementary for a good decision-making. While

CBR takes advantage retrieving the history of

previous cases, whereas EBP aims finding

documents containing updated evidence based

consolidated research results (see Figure 1).

INTEGRATING CASE-BASED REASONING WITH EVIDENCE-BASED PRACTICE FOR DECISION SUPPORT

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While CBR search uses a structured case-base,

usually presented in the organizational environment

of the problem, the EBP approach searches evidence

in unstructured document usually obtained over the

Internet.

We describe the integration preserving

compatibility with the classic model on CBR.

1. Retrieve cases - Obtain cases with similar

problems to new case and antecedent cases of the

motivator agent. In the retrieve the search is textual

and the key terms in the new case are confronted

with the contents of the attached evidence, in

addition to the content of the founded cases. The

similarity calculation considers the attached

evidence with its associated weight.

2. Retrieve and process research evidence – It

contains four sub-activities:

2.1 - Transform problem in question – it aims to

build a template, from a given problem, to conduct

the research for documents containing evidence;

2.2 - Evidence Retrieval – obtain documents that

contain evidences considering the template

previously made. It is based on Information

Retrieval techniques involving similarity metrics and

ranking schemes;

2.3 - Critical Evaluation – this sub-activity includes

steps for the selection, the rejection and the

acceptance of documents, besides of evidences

extraction;

2.4 - Selects the best research evidence – involves

the consolidation of evidences showing result

presentation and discussion, considering aspect

several, e.g., practical decisions, methodological

limitations, quality of original material, etc. (Muñoz

et al., 2002).

3. Reuses – The first reuse activity treats the

construction of new solutions, with mechanisms for

adjustments and adaptations, considering (i) similar

cases solutions (or part of them), (ii) historical of

motivator agent cases, and (iii) the best research

evidence confronted with attached evidences to

similar cases. It corresponds to classic solution on

CBR. The second reuse activity must collect the

values and preferences of the motivator agent and

request his/her participation in decision-making.

Reuse examples: (i) medical diagnosis and

treatment; (ii) judgment and designation of

activities/service institutions to penal execution.

4. Revise and Retain – The same of the classic

model on CBR.

3 EXAMPLE – APPLICATION TO

CRIMINAL JUSTICE

This example is applied on a real case of abortion

from the State of Bahia Court, Brazil, whose

practice is considered a crime. The subject of the

new case is “voluntary abortion”.

The Table 1 contains the general evidence and

case structure for criminal justice. A prototype was

developed in Java language that interacts with the

framework JColibri using the CBR model (Bello-

Tomás, 2004).

The Figure 2 presents data of the problem (fact

and his/her author, witness and material proofs).

Figure 2: Data of the problem.

Table 1: Evidence and Case Structure.

Structure Attributes

Problem (fact) Description, Objective, Circumstances, Author (Name, Adress, District, Conduct, Behaviour,

Needs, Risk condition, Preferences), Witness proof (Name, Content, Date), Material proof

(Organization, Content, Date, Responsible person)

Research

Evidence

Question, Defined terms, Keywords for search, Sources, Search criteria, Result (Type of study,

Considerations), Discussion

Solution (trial) Sentence, Criteria, Recommendation (Permit, Institution)

Outcome Final situation, Consequences, Final comments

Learning Procedures to case solution, Comments search for evidences

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Figure 3: Retrieved case for judgment support.

One similar case about therapeutic abortion was

found in the Evidences and Cases Base, but it isn’t

sufficient to give support to the solution, forcing the

judge to search by research evidences (see Figure 3).

The activity Retrieve and process research

evidence began with the transformation of the

problem in a question. Initially, defined terms,

keywords, sources and search criteria are informed.

After analysis of the documents retrieved, the

history of retrieve, the results and discussion are

informed agree with the Figure 4.

Figure 4: Template of the search for evidence.

The first activity reuse was based in evidences

attached to the case, discussion, and the court

sentence was in favour of the "voluntary interruption

of pregnancy", based on criteria of the Brazilian

Penal Code. Aiming to learning, procedures to case

solution describe the steps that it took to reach this

verdict coming to be used in the activity retain. In

the second activity reuse, the preferences of the

pregnant woman were agree with the list of

indicated hospitals (institutions) and medical

surgeons of the court. In the decision with

recommendation, the court attended the

recommendation of the concerned pregnant. It was

consigned a charter authorizing the surgery (permit)

as soon as possible and awaited the final outcome.

4 CONCLUSIONS

This work proposes the integration of CBR with

EBP for decision support. The activities of the basic

cycle of CBR and the systematic steps of the EBP in

the medical and justice areas served of bases for

built this propose.

The main contributions are: (i) representation of

the EBP procedures; (ii) knowledge representation

to retain cases and evidences together; (iii) extension

of CBR regarding evidences attached to the cases;

and (iv) the representation of the EBP procedures

integrated to CBR.

Future researches encompass the formalization

of the computing model towards Evidence and Case-

Based Reasoning and the creation of a semi-

automatic Evidence-Oriented Information Extractor.

REFERENCES

Bello-Tomás, J. J., Gonzáles-Calero, P. A., Diaz-Agudo,

B. (2004). JColibri: An Object-Oriented Framework

for Building CBR Systems. ECCBR (pp. 32–46).

Madrid, Spain.

Loriggio, A. (2002). De onde vêm os problemas. São

Paulo, Brazil: Negócio Editora.

Muñoz, S.I.S., Takayanagui, A.M.M., Santos, C.B.,

Sanchez-Sweatman, O. (2002). Systematic literature

review and meta-analysis. Proc. 8th Brazilian Nursing

Communication Symposium. São Paulo, Brazil.

Pal, S., Shiu, S.C.K. (2004). Foundations of Soft Case-

Based Reasoning. New Jersey: Wiley-Intersciense

publication.

Russel, S., Norvig, P. (2003). Artificial Intelligence: A

Modern Approach. New Jersey: Prentice Hall.

Sackett, D.L., Straus, S.E., Richardson, W.S., Rosenberg,

W., Haynes, R. B. (2001). Evidence-based medicine:

how to practice and teach EBM. New York: Elsevier

Health Sciences.

Warren, R.K. (2007). Evidence-Based Practice to Reduce

Recidivism: Implications for State Judiciaries.

Available: http://works.bepress.com/roger_warren/1.

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