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Stages of change in parents' discussions with their children about HIV/Aids prevention

Abstracts

This study aimed to know the stages of behavior change of parents in relation to communication held with their adolescent children on sex, sexuality and HIV/Aids prevention. Prochask and Diclement' stages of change model was used. Interviews were carried out with 26 parents of adolescents from a public school in Fortaleza, CE, Brazil. Parents were classified according to the stages of change. The majority of them reported talking to their children about the issue or intending to do it, though some of them faced difficulties in doing so. The promotion of further information about HIV/Aids prevention and unwanted pregnancies is needed. Strategies should be developed jointly with families, schools and health services in order to promote better communication in the context of adolescents' family, towards a healthier sexual life for the adolescents.

adolescent; family; HIV; acquired immunodeficiency syndrome; health education; health promotion


Objetivou-se, com este estudo, conhecer o estágio de mudança do comportamento dos pais em relação à comunicação com os filhos adolescentes sobre sexo/sexualidade e medidas preventivas de HIV/AIDS. A Teoria de Estágios de Mudanças, de Prochaska e Diclement foi utilizada como referencial metodológico. Entrevistou-se 26 pais de adolescentes matriculados em uma escola pública do município de Fortaleza, CE, Brasil, classificados nos diferentes estágios de mudança. A maioria relatou que conversam ou têm interesse em conversar com os filhos sobre a temática, apesar de alguns terem evidenciado dificuldades para isso, havendo necessidade de maior esclarecimento sobre medidas preventivas de HIV/AIDS ou gravidez indesejada. Estratégias devem ser criadas juntamente com a família, escola e unidades de saúde para promover melhor comunicação no contexto familiar dos adolescentes, de forma a favorecer-lhes uma vida sexual e reprodutiva mais saudável.

adolescente; família; HIV; síndrome de imunodeficiência adquirida; educação em saúde; promoção da saúde


Este estudio tuvo como objetivo conocer las etapas de cambio del comportamiento de los padres en relación a la comunicación con los hijos adolescentes sobre sexo/sexualidad y medidas preventivas de HIV/SIDA. La Teoría de Etapas de Cambios, de Prochaska y Diclement, fue utilizada como marco teórico. Se entrevistaron 26 padres de adolescentes matriculados en una escuela pública del municipio de Fortaleza, Ceará, Brasil, clasificados en las diferentes etapas de cambio. La mayoría relató que conversan o tienen interés en conversar con los hijos sobre la temática, a pesar de que algunos reconocieron tener dificultades para esto, habiendo la necesidad de un mayor esclarecimiento sobre las medidas preventivas de HIV/SIDA o de gravidez indeseada. Las estrategias deben ser creadas juntamente con la familia, escuela y unidades de salud para promover una mejor comunicación en el contexto familiar de los adolescentes, de forma a proporcionarles una vida sexual y reproductiva más saludable.

adolescente; familia; VIH; síndrome de inmunodeficiencia adquirida; educación en salud; promoción de la salud


ARTIGO ORIGINAL

Stages of change in parents' discussions with their children about HIV/Aids prevention1 1 Universidade Federal do Ceará, Brasil: This research was supported by Council for Scientific and Technological Development, CNPq, Brazil, Process nº 409365/2006-8;

Stella Maia BarbosaI; Patrícia Neyva Pinheiro da CostaII; Neiva Francenely Cunha VieiraIII

IUniversidade Federal do Ceará, Brasil: Nursing undergraduate student, e-mail: stella.mb@ig.com.br

IIUniversidade Federal do Ceará, Brasil: Ph.D. in Nursing, Adjunct Professor, e-mail: neyva@ufc.br

IIIUniversidade Federal do Ceará, Brasil: Ph.D., Adjunct Professor, e-mail: neivafrancenely@hotmail.com

ABSTRACT

This study aimed to know the stages of behavior change of parents in relation to communication held with their adolescent children on sex, sexuality and HIV/Aids prevention. Prochask and Diclement' stages of change model was used. Interviews were carried out with 26 parents of adolescents from a public school in Fortaleza, CE, Brazil. Parents were classified according to the stages of change. The majority of them reported talking to their children about the issue or intending to do it, though some of them faced difficulties in doing so. The promotion of further information about HIV/Aids prevention and unwanted pregnancies is needed. Strategies should be developed jointly with families, schools and health services in order to promote better communication in the context of adolescents' family, towards a healthier sexual life for the adolescents.

Descriptors: adolescent; family; HIV; acquired immunodeficiency syndrome; health education; health promotion

INTRODUCTION

The family is considered a relevant social structure in the education of its children in growth and development, especially in terms of sexuality. However, it has been unable to work on children's sexual education due to the difficulties parents report regarding sexual issues(1).

Adolescents have had an intense share in the AIDS epidemic, and the number of cases is substantial among young people. Studies show that the adopted preventive practices basically consist in the distribution of preservatives, which is not fully efficient, and that further research on sexual and reproductive health of these people is needed(2).

Over the years, infection by HIV/AIDS has indistinctly affected men, women, adolescents and children. The initial notion of "risk groups" gave place to the idea of risk behavior, which essentially considers the practices that lead the individual to a higher or lower level of exposure to HIV. Associated to this notion, the concept of vulnerability is also used for individuals or groups as a guide in prevention strategies.

The vulnerability concept has been widely used in situations where there is risk of Aids. The individual's vulnerability to a certain hazard is determined by a series of social and cultural factors(3). Adolescents can be considered vulnerable to the epidemic because while they experience changes typical of their age, they also face situations related to the family structure and living conditions like poverty, unemployment, low education level and violence, in addition to a lack of access to communication means, health services and prevention measures(4).

Health interventions in the social environment adolescents live in should aim to provide them with knowledge and reduce the vulnerability they are exposed to, contribute to the citizens' education, subjects of rights, able to decide and take responsibility for their choices(5).

Thus, this study aims to contribute to improve knowledge regarding families and adolescents in the discussion on sexuality and potential risks of acquiring STD/HIV/Aids.

It aims to investigate, through Prochaska and Diclement's Stage of Changes theory, the stage parents or guardians have reached in terms of their discussions on sex/sexuality with their adolescent children, with a view to changing their behavior with regard to HIV/Aids prevention measures.

METHOD

The study is based on a research carried out in a primary and secondary public school in Fortaleza, CE, Brazil. Participants were parents of adolescents between 10 and 19 years old enrolled in the school above.

Parents who attended a meeting at school were invited to participate in the study. The researcher (first author) also attended this meeting and proposed a conversation, aiming to approach and interact with potential study subjects. After this activity, a schedule of visits was defined, with days and times established and agreed between parents and the researcher, for interviews to be held at their homes.

Data were collected through semi-structured interviews, a field diary and observation. The participants signed a fully detailed free and informed consent term regarding their rights and the research goals. Interviews were tape-recorded.

The home visits presented some advantages for this study because they allowed researchers to better observe the context adolescents live in and capture their families' dynamics. It also represented an opportunity to establish bonds, invite them for educational activities and identify risk situations(6).

The stage of changes theory was used as a guide in the data collection, description and analysis. The stage of changes model distinguishes different stages individuals, groups and families present with regard to health behaviors. In this model, behavior change is considered a process in which people present varied levels of motivation and willingness to change. Stages or levels of change are: pre-contemplation, contemplation, action and maintenance(7). This model helped in the identification of barriers or difficulties to adopt health behaviors, in this case, conversations between parents and adolescent children on sex/sexuality and HIV/Aids preventive measures. Data were organized and analyzed through thematic categories, which were related with the stage of changes proposed by the model.

This study complied with Resolution number 196/96, from the Brazilian National Health Council, which addresses research with human beings, respecting their rights and ethics(8). The Ethics Research Committee at Ceará Federal University approved this study.

RESULTS

To contextualize the study objective, the profile of participants and data regarding the parents' stage of change in relation to conversations with their adolescent children on STD/HIV/AIDS prevention are presented.

The adolescents' parents were invited to participate in the study when they attended a meeting at school with teachers. Eighty-four adolescents' parents or guardians participated in this meeting and 32 (38%) spontaneously manifested their interest to participate in the study. They provided their addresses and phone numbers so that household visits could be held. However, only 26 (31%) parents were interviewed because the remainder either provided incomplete addresses, did not have a telephone or were not available on accessible hours.

Profile of parents participating in the study

Of all those participating in the study, 25 (96%) were female and 01 (4%) male. In terms of age, participants were between 35 and 55 years, with a higher frequency (88.4%) between 35 and 48 years.

Regarding their education level, 14 (53.8%) had incomplete primary school; four (15.3%) had complete primary school; four had complete secondary school; two (7.8%) had never gone to school; one (3.9%) had incomplete secondary school and 01 (3.9%) had incomplete higher education.

Distribution between working and non-working parents was balanced: 15 (57.6%) did not have formal work (housewives); 11 (42.4%) worked, though 09 (81.8%) of them worked at home (as dressmakers or craftworkers) and 02 (18.2%) worked out-of-home.

In terms of economic status, 11 (42.3%) reported family income lower than one minimum wage; nine (34.6%) between one and two minimum wages; four (15.4%) reported three minimum wages and two (7.7 %) reported an income of four minimum wages.

Regarding the number of children, the study shows that 14 (53.8%) parents have one to two children; nine (34.6%) have three to four children, and three (11.6%) have five children. The distribution of children regarding gender was balanced; parents of 69 adolescents (100%) were interviewed, 39 (56.5%) female and 30 (43.5%) male.

Adolescents' age is uniformly distributed: 23 (33.3%) are between 11 and 13 years; 21 (30.4%) between 14 and 16 years; 23 (33.3%) between 17 and 19 years and two (3%) are 20 years old.

Propositions that reflect the different stages of change were created from the thematic categories originated in the parents' reports.

Parents' Stages of change in relation to their conversations with children on the prevention of STD/AIDS

Stage of change: Pre-contemplation

The following was used in this study as a proposition to characterize the pre-contemplation stage: "Parents do not recognize their adolescent children's risk of infection by HIV/Aids, even being aware of the disease's existence". In this stage, the informants' statements show low perception of risk for their adolescent children.

Parents were asked whether their children were at risk of acquiring STD/HIV/Aids and 20 (77%) of them answered NO, providing the following justifications:

They are not at risk of acquiring these diseases because we talk to them (children); because we know they protect themselves; because they are smart and will not get into it (B).

There is no risk because I know they don't walk around with drugged people, neither prostitutes (H).

Among parents who believe their children are at some risk, 06 (23 %), report that:

There is always some risk; because I don't know if they'll always use condoms (A).

Everybody is at risk because the condom can tear; one day they might forget to use it (C).

What characterized this stage of change most strongly were reports regarding the risk of acquiring STD/HIV/Aids. Some parents fit in this stage of change, however, according to the following statements:

I don't talk about this issue with my son because I don't like to talk about it. I feel embarrassed. He can talk about this with friends or at school if he wants to (F).

Mothers should not talk about this, because children are not respecting their mothers anymore... Imagine if we talk about something like this (R).

Stage of Change: Contemplation

In this study, the following proposition was used to characterize the contemplative stage: "Parents acknowledge their children's risk of infection by STD/HIV/Aids but do not talk with them about the issue or do not see the need of talking to them yet". In this stage, reports show the concern with the risks of acquiring STD/HIV/Aids but do not show interest or motivation to talk with their children, according to the following reports:

I know there's always the risk of getting these diseases, but I think that nothing is going to change if I don't talk about it with them (F).

I'm somewhat interested in talking to them, though there are smart, because I know they've attended lectures at the health unit and at school and more knowledgeable people are better than I to talk with (...) I've never talked about HIV and Aids because I don't know how to explain it to them, I feel embarrassed (C).

Regarding conversation on the specific theme "HIV/Aids", the majority of parents [19 (73%)] said they did not talk about it, because they do not know how to talk about this issue; because they did not see the need to talk about it yet or did not have the opportunity to do it. Some parents [07 (27%)] said they had already talked about it, either when they had seen their children arriving with condoms or when the subject was on TV.

Stage of change: action

The proposition adopted for the stage of action was: "Parents perceive the importance of clarifying their children on the sex/sexuality issue and preventive measures against HIV/Aids and talk to them about it". In this phase, informants show concern and interest in talking to their children about this topic, as follows:

I always talk about it 'cause I think it is necessary and if we don't, they can get a disease because of a lack of explanation (L).

I'm interested in talking to my daughters because nowadays, all you see are these young girls pregnant in hospitals (G).

Twenty-four (92.3%) parents show interest in talking to their children about sex/sexuality, despite difficulties some face to address the issue; two (7.7%) of them said they had no interest in talking to their children because they deemed it unimportant and had no stimulus or motivation to do it.

Twenty-two (84.6%) parents reported that they really talk to their children about sex/sexuality because they think it is important to provide explanations on the subject; two (7.7%) report that they rarely talk about it because it is very difficult for them due to embarrassment, insecurity and because they do not feel motivated to do so and two (7.7%) said they do not talk about it because they do not think this is an important practice.

Stage of change: maintenance

The proposition used to characterize the maintenance stage was: "Parents talk to adolescent children on sex/sexuality and HIV/Aids preventive measures and search for information to better explain it to the children in future conversations". In this stage, informants show interest in searching information to better clarify their children on the subject. Few parents fit in this stage of behavior, however, according to the reports:

I talk a lot with my daughters and look for information, whenever I think it's necessary, with people who have more knowledge than I do. I only know this world here and more knowledgeable people know the world out there and are able to give better explanations than I do"(N).

I always go the gynecologist and get information, I ask about any doubts I have or my daughters, things they've asked me and I didn't know how to answer. They hardly ask me anything I can't answer, but when they do, I say: "Child, I'll ask and tell you later!" I take notes of any doubts I have and take them with me to ask (P).

In total, 14 (53.8%) parents look for some source of information to clarify their doubts or those of their children, on sex/sexuality; five (35.8%) of them reported TV as a source of information; three (21.4%) mentioned school; three (21.4%) said they talked to friends or relatives; and three (21.4%) looked for health professionals to clarify their doubts. From those who reported not to look for information on the subject, 12 (46.2%) reported either lack of interest, did not know where to look for or never needed to clarify any doubts.

All parents approved their children talking about sex/sexuality at school.

DISCUSSION

Profile of study participants

The high percentage of women in the study was predictable due to the great responsibility given to women in children's education, especially in terms of sexuality(9).

It is believed that education is a factor that influences the communication process between parents and children. Low education level can be a difficulting factor for dialog with children on sexuality, as well as for access to information on sex/sexuality and HIV/Aids preventive measures. The parents' economic condition is evidenced by the low education level, the fact that the majority of participants in this study do not work and also by the activities some mothers perform to help in their families' income.

Regarding the number of children, the result shows these parents do not have many children. It used to be more common to find large families, especially among those with low education level and purchasing power(10). Regarding the adolescents' age, parents are interested in participating in a study regarding conversations about their children's sexuality in the initial or final phases of adolescence and are not concerned with girls only, as sex/sexuality used to be culturally treated.

Parents' stages of change in relation to conversation with children regarding STD/Aids prevention

The study analysis revealed parents who report talking with their children about sex/sexuality and HIV/Aids preventive measures (action stage). On the other hand, in one of the reports, the parent does not attribute risk of HIV/Aids infection to his(er) children, because they were not friends with "risk groups" (pre-contemplative stage). According to the Stage of change theory(11), the individual does not go through stages linearly. The changes of stages are better represented as a spiral in which people can progress or regress without a logical order.

In general, the majority of parents reported talking or interest in talking to children on the subject, though some of them admitted difficulties in doing so. However, it is observed that these talks occur superficially. There is no clarification on STD/HIV/Aids preventive measures or on how to prevent an unwanted pregnancy.

The pre-contemplative stage is defined as a stage in which there is no intention to change, not even a critique regarding the conflict involving the behavior-problem(7) (in the case of discussions on sex/sexuality with their adolescent children). In this stage, reproduced reports show that these parents did not perceive the risk of acquiring STD/HIV/Aids which their adolescent children are exposed to and some did not show interest in talking to their children about the issue, neither reported any intention to change.

It is said that people are in the contemplation stage as they start to admit there is a problem and consider the need to face it, but do not really do it(12). In this stage, the described reports show that parents perceived the problem but alleged difficulties in talking to their children on sex/sexuality, especially about HIV/Aids, and there was no intention of changing this behavior in a near future. It is believed that this result illustrates the difficulty of parents in explaining their children about HIV/Aids, which can be related to the parents' low education and difficulty in obtaining information on the subject.

The action stage is when the client chooses a strategy to realize the change of behavior and make it happen. Described reports show that these parents were interested and had the attitude to manage talking to their children. Results show that the majority of parents took interest in talking to their children about the issue, but not all of them actually did it, and some even reported difficulties in their dialog with children. It shows that these parents are susceptible to change of behavior, that is, activities of education in health would encourage dialog on sexuality and HIV/Aids preventive measures.

The results show that, in the maintanence stage, some parents did not look for any kind of information to better inform their children, and those who did used the most accessible means, especially TV or friends/relatives, which are not always sufficient. Regarding discussions on sex/sexuality at school, parents who were interested in talking with their children supported the school's initiative of promoting debates on the subject. Those parents who did not talk to children about sex/sexuality delegated this responsibility to school, since they did not do it for several reasons, like embarrassment and lack of interest, among others. Maintenance is the stage in which continuity of a behavior aquired during the action stage is encouraged. It is a difficult phase but necessary for the ideal behavior. Few parents fit in this stage of change, however, showing interest in searching for information to clarify their own doubts and better dialog with their children. Thus, an important role of nurses, as educators in health, is to help these individuals to reach this stage of health behavior.

FINAL CONSIDERATIONS

Studies carried out using Stage of change theory were validated in several health behaviors, including alcohol consumption, smoking and preservative use(13). In contact with this theory, it is perceived that evaluating motivational stages with a view to the motivation to change is the essential path for professionals working with health prevention and promotion, working towards sound results with individuals and families.

This study showed that parents are in different stages of change in terms of their participation in the HIV/Aids prevention of their adolescent children, that is, varying from pre-contemplation to maintenance. The difficulty in talking about sex/sexuality, the lack of interest in searching for information on these issues or even lack of knowledge were obstacles that impeded parents to play a more pro-active role in the prevention of this epidemic.

In this perspective, it can be inferred that adolescents are socially vulnerable due to the low or limited family support they receive in terms of preventive behavior.

It is necessary to work with families to devise means to strenghthen, mobilize and encourage them to reach equilibrium and wellbeing, transcending the biological aspects of family members and finding strategies to facilitate the development of daily tasks, whether directly or indirectly related to health. At the same time, supporting the family in its educative role is also necessary, stressing its value and capacity to educate(14).

This study showed that the majority of parents have the interest and motivation to talk to their adolescent children. Nevertheless, it is necessary to create means and strategies to work with these parents, so that they can help their children to have healthy sexual and reproductive lives.

Therefore, strategies should be created to promote adolescents' health jointly with the family, school and health units because, when these social actors are united, understanding the adolescents' difficulties in the face of the epidemic will be more feasible, with a view to the achievement of the adolescents' health promotion and prevention.

REFERENCES

1. Dias ACG, Gomes WB. Conversas sobre sexualidade na família e gravidez na adolescência: a percepção dos pais. Estudos Psicología 1999 janeiro-junho; 4(1):79-106.

2. Borges ALV, Schor N. Homens adolescentes e vida sexual: heterogeneidades nas motivações que cercam a iniciação sexual. [Online] [Acesso em: 20/10/07]. Disponível em: http://www.scielo.br/scielo.php?script=sci_arttext&pid =S010211X2007000100024&lng=en&nrm=iso&tlng=en

3. Seffner F. O conceito de vulnerabilidade: uma ferramenta útil em seu consultório [online] [Acesso em 17/03/08] Disponível em: http://ww1.unilasalle.edu.br/seffner/artigo4.htm

4. Castro MG, Abramovay M, Silva LB. Juventude e sexualidade. Brasília (DF): UNESCO Brasil; 2004.

5. Secretaria da Saúde (SP). Manual de atenção à saúde do adolescente. São Paulo (SP): SMS; 2006.

6. Ministério da Saúde (BR). Saúde integral de adolescentes e jovens: orientações para a organização de serviços de saúde. Brasília (DF): Ministério da Saúde; 2005.

7. Prochaska JO, Diclemente C. Transtheorical therapy: toward a more integrative model of change. Psycotherapy: theory, research and practice 1982; 20:161-73.

8. Ministério da Saúde (BR) Conselho Nacional de Saúde. Brasília (DF): Ministério da Saúde; 2002.

9. Borges ALV, Nichiata LYI, Schor N. Conversando sobre sexo: a rede sociofamiliar como base de promoção da saúde sexual e reprodutiva de adolescentes. Rev Latino-am Enfermagem 2006 maio-junho; 14(3):422-7.

10. Instituto Brasileiro de Geografia e Estatísticas, IBGE. Censo demográfico 2000: características da população e dos domicílios. Rio de Janeiro (RJ): IBGE; 2001.

11. Prochaska JO, Diclemente CC, Norcross JC. Search of how people change: Applications to addictive behaviors. Am Psychol 1992; 47:1102-13.

12. Toral N, Slater B. Abordagem do modelo transteórico no comportamento alimentar. [online] [Acesso em: 01/05/07] Disponível em: http://www.abrasco.org.br/cienciaesaudec oletiva/artigos/artigo_int.php?id_artigo=452.

13. Yoshida EMP. Escala de estágios de mudança: uso clínico e em pesquisa. Psicologia USP 2002 janeiro-junho; 7(1):59-66.

14. Marconi SS. Criando os filhos e construindo maneiras de cuidar. In.: Else I, Marconi SS, Silva MRS, organizadoras. O viver em familia e sua interface com a saúde e a doença. 2. ed. Maringá: Eduem; 2004.

Recebido em: 16.8.2007

Aprovado em: 10.8.2008

  • 1. Dias ACG, Gomes WB. Conversas sobre sexualidade na família e gravidez na adolescência: a percepção dos pais. Estudos Psicología 1999 janeiro-junho; 4(1):79-106.
  • 3. Seffner F. O conceito de vulnerabilidade: uma ferramenta útil em seu consultório [online] [Acesso em 17/03/08] Disponível em: http://ww1.unilasalle.edu.br/seffner/artigo4.htm
  • 4. Castro MG, Abramovay M, Silva LB. Juventude e sexualidade. Brasília (DF): UNESCO Brasil; 2004.
  • 5
    Secretaria da Saúde (SP). Manual de atenção à saúde do adolescente. São Paulo (SP): SMS; 2006.
  • 6
    Ministério da Saúde (BR). Saúde integral de adolescentes e jovens: orientações para a organização de serviços de saúde. Brasília (DF): Ministério da Saúde; 2005.
  • 7. Prochaska JO, Diclemente C. Transtheorical therapy: toward a more integrative model of change. Psycotherapy: theory, research and practice 1982; 20:161-73.
  • 8
    Ministério da Saúde (BR) Conselho Nacional de Saúde. Brasília (DF): Ministério da Saúde; 2002.
  • 9. Borges ALV, Nichiata LYI, Schor N. Conversando sobre sexo: a rede sociofamiliar como base de promoção da saúde sexual e reprodutiva de adolescentes. Rev Latino-am Enfermagem 2006 maio-junho; 14(3):422-7.
  • 10
    Instituto Brasileiro de Geografia e Estatísticas, IBGE. Censo demográfico 2000: características da população e dos domicílios. Rio de Janeiro (RJ): IBGE; 2001.
  • 11. Prochaska JO, Diclemente CC, Norcross JC. Search of how people change: Applications to addictive behaviors. Am Psychol 1992; 47:1102-13.
  • 12. Toral N, Slater B. Abordagem do modelo transteórico no comportamento alimentar. [online] [Acesso em: 01/05/07] Disponível em: http://www.abrasco.org.br/cienciaesaudec oletiva/artigos/artigo_int.php?id_artigo=452
  • 13. Yoshida EMP. Escala de estágios de mudança: uso clínico e em pesquisa. Psicologia USP 2002 janeiro-junho; 7(1):59-66.
  • 14. Marconi SS. Criando os filhos e construindo maneiras de cuidar. In.: Else I, Marconi SS, Silva MRS, organizadoras. O viver em familia e sua interface com a saúde e a doença. 2. ed. Maringá: Eduem; 2004.
  • 1
    Universidade Federal do Ceará, Brasil: This research was supported by Council for Scientific and Technological Development, CNPq, Brazil, Process nº 409365/2006-8;
  • Publication Dates

    • Publication in this collection
      16 Feb 2009
    • Date of issue
      Dec 2008

    History

    • Received
      16 Aug 2007
    • Accepted
      10 Aug 2008
    Escola de Enfermagem de Ribeirão Preto / Universidade de São Paulo Av. Bandeirantes, 3900, 14040-902 Ribeirão Preto SP Brazil, Tel.: +55 (16) 3315-3451 / 3315-4407 - Ribeirão Preto - SP - Brazil
    E-mail: rlae@eerp.usp.br