SciELO - Scientific Electronic Library Online

 
vol.21 número1Livro infantil especializado como estratégia de prevenção do abuso sexualRisk factors, psychosocial protection, and work: organizations that emancipate or kill índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados

Journal

artigo

Indicadores

Compartilhar


Psicologia: teoria e prática

versão impressa ISSN 1516-3687

Psicol. teor. prat. vol.21 no.1 São Paulo jan./abr. 2019

https://doi.org/10.5935/1980-6906/psicologia.v21n1p220-235 

ARTICLES
HUMAN DEVELOPMENT

 

Relations among adolescents' life purpose, household chores, and school performance

 

Relaciones entre proyectos de vida, tareas domésticas y desempeño escolar en adolescentes

 

 

Fredericko WichmannI; Letícia L. Dellazzana-ZanonII; Lia Beatriz de L. FreitasIII; Marco Antônio P. TeixeiraIV

IInstitute of Psychology, Federal University of Rio Grande do Sul (UFRGS)
IIPsychology School, Pontifical Catholic University of Campinas (PUC-Campinas)
IIIInstitute of Psychology, Federal University of Rio Grande do Sul (UFRGS)
IVInstitute of Psychology, Federal University of Rio Grande do Sul (UFRGS)

Mailling address

 

 


ABSTRACT

This study investigated relations among adolescents' life purposes, household responsibilities, and school impairment. Participants were 113 Brazilian adolescents, between 14 and 16 years old, students from municipal schools. The instruments were a record of biosociodemographic data, the Household and Sibling Care Questionnaire, and a written testimony of life purpose. Results indicated a significant difference for the relation among household responsibilities level and purposes related to material goods (t = -2.88, p = 0.00), and no significant results for school performance variables. However, when the sample was stratified by sex, different relations were found, and school impairment was only found in the female group (t = -3.13, p = 0.00). We concluded that there are relations among the investigated variables, which justifies new studies, and that the sex variable should be considered when analyzing these relations.

Keywords: purpose; household responsibilities; gender; adolescence; development.


RESUMEN

Este estudio investigó relaciones entre proyectos de vida, tareas domésticas y prejuicios en el desempeño escolar en adolescentes. Participaron 113 adolescentes brasileños, de 14 a 16 años, alumnos de escuelas municipales. Se utilizó una ficha de datos biosociodemográficos, el Cuestionario de Tareas Domésticas y Cuidado entre Hermanos y un testimonio escrito sobre proyectos de vida. Los resultados indicaron diferencia significativa para la relación entre tareas domésticas y proyectos relacionados con bienes materiales (t = -2,88, p = 0,00), y ninguna diferencia significativa en las variables de desempeño escolar. Sin embargo, cuando estratificada la muestra por sexo, se encontraron relaciones diferentes, y perjuicio escolar sólo en el grupo femenino (t = -3,13, p = 0,00). Se concluyó que hay relaciones entre las variables investigadas, lo que justifica la realización de nuevos estudios, y que se debe considerar la variable sexo cuando se analizan esas relaciones.

Palabras clave: proyectos de vida; tareas domésticas; género; adolescencia; desarrollo.


 

 

1. Introduction

The objective of this study was to investigate relations among life purposes, household chores, and poor school performance among adolescents.

Planning life is an essential task in an individual's development and the way it takes place changes throughout all phases of human development, though during adolescence, it is a concrete possibility considering the cognitive, affective, and moral advancements that take place during this period (Dellazzana-Zanon & Freitas, 2015). Studies suggest that life purposes are essential during adolescence and their presence is associated with psychological well-being and achievements in adult life, in addition to playing an essential role in the establishment of self-concept (Massey, Gebhardt, & Garnefski, 2008).

A scientific interest for life purposes recently emerged (Lewis, Turiano, Payne, & Hill, 2016). In a literature review, Dellazzana-Zanon and Freitas (2015) report that most of the revised studies (63.6%) did not present an explicit definition of life purpose, while differences between concepts were found among those that did present a clear definition. In this paper, life purpose is considered "a set of aspirations one intends to achieve by means of steps to be overcome toward an ideal, which permits organization and orientation towards its accomplishment in the future" (Silveira, Machado, Zappe, & Dias, 2015, p. 53).

Studies report evidence that contextual factors such as environment, family, peers, and activities are determinant for the planning of life purposes (Massey et al., 2008). Few empirical studies, however, investigate what such factors are, especially among samples from vulnerable populations. In this sense, studies addressing socioeconomic differences in the development of life purposes are needed (Bronk, 2014).

A potential factor of influence that is present mainly in low-income families has to do with household chores. There is a discussion about which tasks should be included in this category, and also about the boundaries in terms of household chores performed during childhood and adolescence between what is considered part of the familial experience and domestic child labor, which is prohibited for those under 18 years old (Patriota & Alberto, 2014).

Even though a clear definition of this concept had not been established at the time, a synthesis of the Social Indicators provided by the Brazilian Institute of Geography and Statistics [IBGE] (2015) included the following tasks under the household chores category: a) clean or tidy up part of or the entire home; b) cook or prepare meals, iron clothes, do the laundry or the dishes, using electrical appliances or not to perform tasks for oneself or other residents; c) instruct or supervise domestic workers performing household chores; d) take care of children or minors; and e) clean the backyard or area around the house. The last IBGE survey found that 37.6% of Brazilian boys and 68.5% of Brazilian girls aged from 10 to 15 years old reported the performance of household chores. The impact of these responsibilities on the development of these individuals, however, has not yet received the attention it deserves.

There is not a consensus among researchers about the participation of youths in household chores. On the one hand, authors suggest that household chores may negatively affect development because, in addition to having little time for leisure, adolescents who perform household chores have their school performance affected, more frequently miss classes, and experience school failures, and have less time to do school work (Dellazzana-Zanon, Zanon, & Freitas, 2014). This factor is also related to life purposes because school performance plays a vital role in prospects (Oyserman, Bybee, & Terry, 2006).

On the other hand, authors suggest that positive effects may arise from performing household chores during adolescence as these tasks represent the first "job" with most people are faced. If performed under appropriate conditions, household chores offer the opportunity for adolescents to experience achievement and success as it demand responsibility and independence and promote self-control and persistence, which are considered necessary for the development of self-efficacy (Riggio, Valenzuela, & Weuser, 2010). The study by Pestana et al. (2016), for instance, addresses whether variables related to household chores would influence school performance. The authors found that adolescents who collaborate with family members performing household chores have a better school performance than those who do not.

What are the factors explaining such divergences concerning effects (positive and negative)? In addition to the amount of time spent, Riggio et al. (2010) suggest that differences lie in the quality of tasks, the reasons why parents assign tasks, beliefs of children and adolescents such as whether they are choosing or being "forced" to perform such tasks, and the quality of parental relationships.

Another critical reason may be associated with sex. There seems to be a consensus in the literature (Cunha, André, Aparício, Santos, & Nunes, 2016; Sousa & Guedes, 2016) regarding differences between men and women concerning household chores. Sousa and Guedes (2016) note that, despite considerable changes that have taken place in terms of the sex ratio on the job market and the relations established between work and families in recent decades, household chores remain a primarily feminine responsibility. In a systematic literature review, Cunha et al. (2016) found that this inequality is even more accentuated among low-income families.

In summary, studies indicate that: a) the development of life purposes is an essential developmental task that may be influenced by contextual factors; b) adolescents' performance of household chores is a recurrent phenomenon in Brazil, the effects of which on one's development still demand an investigation; c) performing household chores is related to school performance, which in turn is also related with life purposes; and d) the performance of household chores is established differently between men and women. For these reasons, we propose the following hypotheses: (H1) the frequency and amount of household chores is different between groups with and without the presence of certain areas of life purpose; (H2) the level of household chores is higher among those with poor school performance; and (H3) there are differences in the performance of household chores in function of the adolescents' sex. The objectives of this study were to investigate associations among life purposes, household chores, and poor school performance among adolescents.

 

2. Method

This cross-sectional study with a non-experimental quantitative design is based on a review of studies addressing relations among areas of interest in life purposes, level of household chores, and poor school performance of adolescents (school failure, expulsion or drop out).

2.1 Participants

A total of 113 adolescents attending public schools participated in this study, 61.9% were girls. Inclusion criteria were: a) being between 14 and 16 years old; b) attending a local public school located in (name of the city); and c) living with at least one younger sibling. The average age of the participants was 14.7 years old (SD = 0.8). With regard to education, 4.4% were attending the 5th grade; 12.4% the 6th grade; 38.1% the 7th grade; and 40.7% the 8th grade (4.4% did not report the grade). Students from public schools were recruited because the literature reports that adolescents who perform household chores are more frequently found among those attending public schools. Note that an age group was established to avoid very distinct life purposes between younger and older adolescents.

Regarding the composition of the participants' families, 55% belonged to nuclear families; 20.7% to blended families, and 20.7% to single-parent families. With regard to the parents' education, 57.7% of the mothers and 82.4% of the fathers had not completed the first nine years of formal education. Many families (59.5%) received some financial assistance from the government. Each adolescent had four siblings on average.

2.2 Instruments

Record of Biosociodemographic Data: instrument especially developed for this study to characterize the sample regarding biosociodemographic data and collect information concerning the study's objectives, such as family composition, parents' education, and the following indicators of poor school performance: a) school failure, b) drop out; and c) expulsion.

Household Responsibilities and Sibling Care Questionnaire (HRSCQ): this questionnaire was developed by Riggio et al. (2010) and adapted for the Brazilian population by Dellazzana-Zanon et al. (2014). It is intended to measure variables concerning care provided to siblings (four items) and the performance of household chores (five items, e.g., doing the laundry, cooking), containing a five-point Likert scale where 1) never, 2) once or twice a week, 3) three or four times a week, 4) five or six times a week, and 5) always. Both factors concerning care provided to siblings and household chores present appropriate alpha coefficients, 0.75 and 0.69 respectively.

Written testimony on life purposes (D'Aurea-Tardeli, 2008): it consists of a self-report open-ended question. The participants are asked to write a testimony based on a hypothetical problem-situation: "Think about the person you are today. Imagine yourself ten years from now. Describe how you would like your life to be".

2.3 Data collection

Data were collected in situ from eight local schools located in (name of the city). These schools covered the four regions of the municipal school district. The scores obtained for the five items addressing household responsibilities in the HRSCQ were totaled to identify the level of household chores, considering the frequency and how many tasks were performed. The form addressing biosociodemographic data collected indicators concerning poor school performance: a) failure, b) drop out, and c) expulsion.

2.4 Data analysis

Content analysis (Laville & Dionne, 1999) was used to analyze the written testimony on life purposes. A mixed model was used to categorize items, that is, categories are established beforehand, but they can be modified over the process of data exploration according to what the analysis indicates. The life purposes were grouped into five broad categories concerning areas of interest in the adolescents' life purposes: a) career, b) family, c) material goods, d) good life, and e) virtues. The presence or absence of a given category was coded as 0 when a life purpose was not mentioned or 1 when it was. The category "career" included life purposes related to studies and having a job. The category "family" was composed of life purposes that included the family of origin (e.g., living near parents or siblings) or the constitution of a new family (having a spouse or children). The category "material goods" included life purposes such as the acquisition of goods (e.g., buying a house, a motorcycle, traveling), also including life purposes related to being financially independent and having financial stability. The category of "good life" was composed of life purposes linked to the aspiration of self-happiness and happiness of their families. The "virtues" category was composed of life purposes related to generosity (e.g., giving back or helping others) or other virtues. The life purposes not classified under any of these categories (e.g., having a boyfriend or a girlfriend or staying away from drugs) were coded as others. Two judges independently coded the answers. Inter-rater reliability was estimated using coefficient Kappa, and measures ranged from 0.78 to 1.

Groups were compared to test the three hypotheses (Student's t-test). The mean scores obtained in the HRSCQ by the groups with and without one of the areas of interest in life purposes were compared to check hypothesis 1. For hypothesis 2, the mean scores obtained in the HRSCQ by the groups with and without the presence of poor school performance were compared. Moreover, the same analyses were performed according to sex to test hypothesis 3.

 

3. Results

The hypothesis that the level of household chores would be related to the areas of interest in adolescents' life purposes (hypothesis 1) was partially confirmed. A significant difference was found only between the means obtained by the groups with and without life purposes related to material goods (Table 3.1), that is, those who mentioned the acquisition of material goods in their life purposes scored significantly higher in the HRSCQ.

 

 

The second hypothesis was that there was a relation between the level of household chores and adolescents' school performance. The results for the general sample, however, did not present significant differences between the groups with and without the presence of poor school performance (i.e., failure, drop out, and expulsion).

The third hypothesis suggested that these analyses were performed according to sex. Regarding the level of household chores and areas of interest in life purposes (hypothesis 1), the boys presented results different from those presented by the girls. While the girls presented a significant difference between the means obtained by the groups with and without the presence of life purposes related to material goods, the boys presented significant differences in areas related to virtues and the good life (Table 3.2). These results indicate that, for the boys, the level of household chores is related to a tendency to plan life purposes related to virtues and good life, while for the girls, a higher level of household chores is related to a tendency to plan life purposes linked to the acquisition of material goods. No significant differences were found in the remaining areas of interest between the participants of each group.

 

 

Significant differences were found after stratifying the sample by sex in regard to the relation between the level of household chores and school performance (hypothesis 2), that is, between the means concerning the level of household chores obtained by the groups with and without school failure (having failed at least once). The differences, however, were found only for the girls (Table 3.3), suggesting that the higher the level of household chores, the greater the possibility of girls failing at school.

 

 

4. Discussion

This study investigated relations among life purposes, household chores, and poor school performance among adolescents. The results suggest that the adolescent's life purposes may be associated with the performance of household chores while this association may be mediated by a different relation established between sexes and household chores. In general, these findings support ideas that: a) the adolescent's cultural context needs to be taken into account to better understand their life purposes (Bronk, 2014; Dellazzana-Zanon et al., 2014); b) performing household chores is a contextual factor that may influence the development of life purposes (Massey et al., 2008).

Initially, we verified that a higher level of household chores was only associated with the presence of life purposes related to material goods. Perhaps the need to perform a high level of household chores during adolescence leads to a more significant concern with material aspects in the future. Note that the interest of adolescents in material goods does not necessarily have a negative connotation. Csikszentmihalyi and Rochberg-Halton (1981) explain that there are different forms of materialism: instrumental and terminal materialism. Terminal materialism is when the search for material possession has no other purpose rather than possession itself, with the intention to cause envy or admiration in others or as a symbol of status. These authors argue that material possessions may be positive in life when they have an instrumental nature, that is when they serve as a means to seek and support personal values and life purposes.

In a later analysis, however, we found that the relationship between life purposes and household chores is different between boys and girls. Even when the level of household chores is equivalent, the relations established between the factors were different. While significant differences were found in the area of material goods for the girls, the boys presented significant differences with regard to the other two areas of interest: good life and virtues.

The findings related to girls are in agreement with various studies reporting differences between female and male groups concerning materialism (Ladeira, Santini, & Araújo, 2016); female children and adolescents find shopping more pleasurable. Most material goods mentioned by the girls in this sample, however, are things that lack in their lives and their families - such as not having a house of their, a car, for instance -, which characterizes the instrumental materialism mentioned by Csikszentmihalyi and Rochberg-Halton (1981).

At a first glimpse, the association between household chores and life purposes of a good life, identified among the boys, seems to indicate that having a higher level of household chores would lead them to include aspirations regarding their happiness and that of their families in their life purposes. A more detailed analysis of the boys' responses included in this category, however, shows that most boys provided simplistic answers (e.g., being happy). Such answers may indicate a lack of life purposes with well-established aspirations and goals rather than the presence of a real ethical aspiration. Future studies are needed to understand why there is this relationship with household chores and why this relation appears only for the boys.

To understand the association between household chores and virtues, note that life purposes related to generosity (e.g., helping others) predominated. This relation may be understood from the logic of solidarity. The study conducted by Grusec, Goodnow, and Cohen (1996) suggests that having household chores may lead to greater consideration for others. The fact that adolescents are supportive in the present helping out with household tasks may make a difference with what they want for the future. According to Amazonas, Damasceno, Terto, and Silva (2003), this rationale is typical of low-income families. These authors note that this type of family has to establish survival strategies in which the entire family network needs to collaborate with the maintenance of the group. For this reason, family members promote a supportive relationship, which "reorders values and subordinates personal accomplishments to the interests or needs of the family group" (Amazonas et al., 2003, p. 13).

Once again, we should note that the relation with generosity found in this sample is linked to the gender of the adolescents and is present only among the boys. These results should not be interpreted as boys being more generous than girls; instead, the interpretation is that household chores influence this relation only for the boys, not for the girls. Because culturally, the social role of men is more frequently associated with a paid job to support the family, there is a symbolic construction that household chores are women responsibilities (Sousa & Guedes, 2016). Therefore, it is possible that when men perform household chores, they interpret that they are helping with something that is not their obligation. This interpretation may explain the intention to reproduce this "generosity" in their life purposes.

Differences between the sexes concerning household chores were also observed in the association with poor school performance. The results show a negative association between these two variables, as opposed to data reported by Pestana et al. (2016). This negative association, however, may indicate that a higher level of household responsibilities leads to a tendency, only among girls, to have failed at least once at school.

Note that the entire sample presents academic delay, that is, 14-year-old adolescents are supposed to attend the 9th grade, but the adolescents addressed in this study are a year behind. Dellazzana and Freitas (2010) found that this gap between age and school grade tends to be large among adolescents from lower socioeconomic background. These authors note that low family income is related to poor access to child education and with high levels of school failure. This finding, however, does not explain the difference between boys and girls concerning household chores and poor school performance.

A potential explanation for this difference between the sexes is the fact that the instrument used to measure the level of household chores considers how frequently tasks are performed (how many times a week) rather than the time spent with tasks. According to data from IBGE (2015), girls spend 60% more time on this type of activity on average (i.e., 12.6 weekly hours compared to 7.9 hours for the boys).

Another explanation is that girls more frequently become responsible for the care of their siblings, as verified by Dellazzana and Freitas (2010), who report that adolescents responsible for caring for their younger siblings tend to miss classes more frequently, have less time to study, and present higher dropout rates.

Note that this study presents some limitations: a) the sample is small, which impedes the generalization of results; b) the statistical design adopted here does not allow for the establishment of cause and effect relations among the phenomena under study; c) the instrument used to collect data concerning life purposes - a single self-reported question - does not provide further information regarding the level of elaboration of life purposes and the underlying motivations; and d) the HRSCQ assesses how frequently household tasks are performed (how many times a week) rather than the amount of time spent, a variable that may explain the differences found between the sexes.

Nevertheless, this paper brought essential contributions to developmental psychology both with regard to life purposes and household chores. About life purposes, a greater understanding was obtained with regard to which daily activities may influence which area of future plans that adolescents devised. What the household chores are concerned, advancement was also achieved in terms of the potential consequences of these tasks - both for life purposes and school performance - reaffirming that this phenomenon is still negatively affected by gender inequality present in our society.

The results presented here reveal the need for more studies adopting more robust samples that allow for the generalization of results. Additionally, to better understand the relations discussed in this paper, we suggest that the time spent on household chores is included as a variable and that qualitative studies are conducted to identify the beliefs of adolescents with regard to household chores and their relations with their life purposes.

 

References

Amazonas, M. C. L. A., Damasceno, P. R., Terto, L. M. S., & Silva, R. R. (2003). Arranjos familiares de crianças das camadas populares. Psicologia em Estudo, 8,11-20. doi: 10.1590/S1413-73722003000300003        [ Links ]

Bronk, K. C. (2014). Purpose in life: A critical component of optimal youth development. Springer: Netherlands.         [ Links ]

Cunha, M., André, S., Aparício, G., Santos, E., & Nunes, C. (2016). Organization of housework in heterosexual couples: Systematic review of the literature. Procedia - Social and Behavioral Sciences, 217(5),459-469. doi: 10.1016/j.sbspro.2016.02.014        [ Links ]

Csikszentmihalyi, M., & Rochberg-Halton, E. (1981). The meaning of things: Domestic symbols and the self. Cambridge: Cambridge University Press.         [ Links ]

D'Aurea-Tardeli, D. (2008). A manifestação da solidariedade em adolescentes: Um estudo sobre a personalidade moral. Psicologia Ciência e Profissão, 28(2),208-303. doi: 10.1590/S1414-98932008000200006        [ Links ]

Dellazzana, L. L., & Freitas, L. B. L. (2010). Um dia na vida de irmãos que cuidam de irmãos. Psicologia: Teoria e Pesquisa, 26(4),595-603. doi: 10.1590/S0102-37722010000400003        [ Links ]

Dellazzana-Zanon, L. L., & Freitas, L. B. L. (2015). Uma revisão de literatura sobre a definição de projeto de vida na adolescência. Interação em Psicologia, 19(2),281-292.doi: 10.5380/psi.v19i2.35218        [ Links ]

Dellazzana-Zanon, L. L., Zanon, C., & Freitas, L. B. (2014). Adaptação do questionário de tarefas domésticas e de cuidado de irmãos. Estudos de Psicologia (Campinas), 31(4),477-487. doi: 10.1590/0103-166X2014000400002        [ Links ]

Grusec, J. E., Goodnow, J. J., & Cohen, L. (1996). Household work and the development of concern for others. Developmental Psychology, 32,999-1007. doi: 10.1037/0012-1649.32.6.999        [ Links ]

Instituto Brasileiro de Geografia e Estatística - IBGE (2015). Trabalho infantil e trabalho infantil doméstico no Brasil: Avaliação a partir dos microdados da Pnad/IBGE (2012-2013). Rio de Janeiro: IBGE. Retrieved from http://www.fnpeti.org.br/biblioteca/ver/615-trabalho-infantil-e-trabalho-infantil-domestico-no-brasil.html        [ Links ]

Ladeira, W. J., Santini, F. O., & Araújo, C. F. (2016). Comportamento materialista em adolescentes e crianças: Uma meta-análise dos antecedentes e dos consequentes. Revista de Administração Contemporânea, 20(5),610-629. doi: 10.1590/1982-7849rac2016150151        [ Links ]

Laville, C., & Dionne, J. (1999). A construção do saber: Manual de metodologia da pesquisa em ciências humanas. Porto Alegre: Artmed.         [ Links ]

Lewis, N. A., Turiano, N. A., Payne, B. R., & Hill, P. L. (2016). Purpose in life and cognitive functioning in adulthood. Aging, Neuropsychology and Cognition, 23(1),1-10. doi: 10.1080/13825585.2016.1251549        [ Links ]

Massey, E., Gebhardt, W., & Garnefski, N. (2008). Adolescent goal content and pursuit: A review of the literature from the past 16 years. Developmental Review, 28(4),421-460. doi: 10.1016/j.dr.2008.03.002        [ Links ]

Oyserman, D., Bybee, D., & Terry, K. (2006). Possible selves and academic outcomes: How and when possible selves impel action. Journal of Personality and Social Psychology, 91,188-204. doi: 10.1037/0022-3514.91.1.188        [ Links ]

Patriota, G. F. R., & Alberto, M. F. P. (2014). Trabalho infantil doméstico no interior dos lares: As faces da invisibilidade. Estudos e Pesquisas em Psicologia, 14(3),893-913.         [ Links ]

Pestana, L., Duarte, J., Coutinho, E., Chaves, C., Nelas, P., & Amaral, O. (2016). Repercussões das atividades domésticas e de lazer no rendimento escolar dos adolescentes. International Journal of Developmental and Educational Psychology, 1(2),347-357. doi: 10.17060/ijodaep.2016.n2.v1.581        [ Links ]

Riggio, H. R., Valenzuela, A. M., & Weiser, D. A. (2010). Household responsibilities in the family of origin: Relations with self-efficacy in young adulthood. Personality and Individual Differences, 48,568-573. doi: 10.1016/j.paid.2009.12.008        [ Links ]

Silveira, K. S. S., Machado, J. C., Zappe, J. G., & Dias, A. C. G. (2015). Projetos futuros de adolescentes privados de liberdade: Implicações para o processo socioeducativo. Psicologia: Teoria e Prática, 17(2),52-63. doi: 10.15348/1980-6906        [ Links ]

Sousa, L. P., & Guedes, D. R. (2016). A desigual divisão sexual do trabalho: Um olhar sobre a última década. Estudos Avançados, 30(87),123-239. doi: 10.1590/S0103-40142016.30870008        [ Links ]

 

 

Mailling address:
Fredericko Wichmann
LAPEGE, Instituto de Psicologia
Rua Ramiro Barcelos, 2600, sala 118
Porto Alegre, RS, Brazil. CEP 90035-003
E-mail: frederickow@hotmail.com

Submission: 08/05/2018
Acceptance: 20/12/2018

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons