Applied Research and Evaluation PREDICTING CHILDHOOD OBESITY PREVENTION BEHAVIORS USING SOCIAL COGNITIVE THEORY AMONG UPPER ELEMENTARY AFRICAN-AMERICAN CHILDREN
SHAKEYRAH ELMORE MANOJ SHARMA, MBBS, MCHES, PH.D. University of Cincinnati, Ohio
ABSTRACT
Childhood obesity is a major public health problem in the African-American community. Commonly suggested public health strategies to reduce childhood obesity are limiting television viewing, encouraging daily moderately intense physical activity of at least 60 minutes per day, increasing fruit and vegetable intake to five or more cups per day, and increasing water consumption. This study examined the extent to which selected social cognitive theory constructs can predict these four behaviors in African-American upper elementary children. A 56-item valid and reliable scale was administered to 222 students. Glasses of water consumed were predicted by self-control for drinking water and self-efficacy for drinking water (R2 = 0.123). Fruits and vegetables consumed were predicted by self-efficacy for eating fruits and vegetables (R2 = 0.083). For designing primary prevention interventions to reduce childhood obesity in the African-American community, social cognitive theory provides a useful framework.
Int’l. Quarterly of Community Health Education, Vol. 34(2) 187-197, 2013-2014 Ó 2014, Baywood Publishing Co., Inc. doi: http://dx.doi.org/10.2190/IQ.34.2.f http://baywood.com 187
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INTRODUCTION Childhood obesity is a major public health concern for the United States. Childhood obesity has tripled since 1980 [1]. African Americans are disproportionally affected by overweight and obesity. Healthy People 2020 estimates that the rate for the black non-Hispanic population is more than one-and-a-half times the rate for their white non-Hispanic counterparts [2]. Childhood obesity among African-American children ages 2-19 is 35.9% [3]. Obesity has a negative and deleterious impact on the physical, social, behavioral, and psychological health of children [4]. It is estimated that the national healthcare expenditures related to overweight and obesity has increased by 68.5 billion dollars from 1998 to 2008 to about 147 billion dollars [5]. Therefore, government initiatives and resources to promote reduction of childhood obesity implemented at the primary level of prevention is an increasing trend. There have also been a substantial number of research studies conducted that have focused on obesity in children. Provisions in the Patient Protection and Affordable Care Act, the First Lady’s Let’s Move initiative, and the recommendations of the Presidential Task Force on Childhood Obesity offers a strong foundation for creating broader initiatives to reduce childhood obesity, but they seldom specifically address racial and ethnic disparities in obesity [6]. It is evident that more successful health education programs need to be implemented, particularly in the African-American community that addresses ethic and cultural differences. The development of obesity in the African-American community is due to a number of influences, including genetic factors and cultural differences, such as those related to diet and social norms, which include the acceptance of surplus weight [4]. Overweight and obesity are likely to persist into adulthood; children who are overweight or obese are more likely than their normal weight counterparts to be overweight or obese as adults. This increases the likelihood of adult diseases [7]. Three of the four top leading causes of death in the African-American community as determined by the Centers for Disease Control and Prevention (CDC) provide obesity, physical inactivity, and diet as risk factors [8]. African Americans who are overweight or obese are more likely to have high cholesterol and high blood pressure, and other factors that increase the risk for heart disease and stroke— which are the top two leading causes of death in the African-American community—and diabetes—which is the 4th leading cause of death in the population [8]. The health disparities which exist in the African-American community are important especially in children, because they have less control over factors that are considered risk factors for obesity, for example environment or socioeconomic status. There is also a lack of research literature related to childhood obesity focusing specifically on African-American children. Social cognitive theory provides a useful framework for designing primary prevention interventions to reduce childhood obesity in African Americans. The
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major personal level constructs of social cognitive theory include self-efficacy, self-control, and expectations. In approaching behavior change, self-efficacy is an important requirement. Self-efficacy describes a person’s confidence in completing a particular behavior at a given moment. Self-control describes a person’s capability to regulate their behavior. Self-control includes strategies which encourage proximal and distal goal-setting and self-rewards. Expectations are the anticipation of the outcome of a particular behavior and the value one places on those outcomes. Different types of expectations include physical outcomes, social outcomes which include approval and disapproval, and self-evaluated positive and negative reactions. Therefore, the purpose of the study was to examine the extent to which social cognitive constructs (self-efficacy, selfcontrol, and expectations) can predict the four behaviors of limiting television viewing, performing daily moderately intense physical activity of at least 60 minutes per day, increasing fruit and vegetable intake to five or more cups per day, and increasing water consumption in upper elementary AfricanAmerican children. METHODS Population and Sample The sample population consisted of 4th through 6th grade African-American students. There were 222 students who participated in the study. The sample population came from three public schools in two large Midwestern cities. In calculating sample size, power was set at 0.80 and alpha was set at 0.05, based on previous studies population correlation coefficient was assumed to be 0.20 and that yielded a sample size of 197 [9]. An approximate 10% inflation to the sample was done to account for missing values. Design The design for the study was cross sectional. The dependent variables were the four behaviors and the independent variables for each behavior were the three constructs of social cognitive theory (self-efficacy, self-control, and expectations) along with gender, age, and whether they had been taught about physical activity and nutrition in school. Instrumentation A 56-item scale was developed and validated in a previous study in a two-round process by a panel of six experts, which included three university professionals and three experts from the school system [10]. Cronbach’s alpha and test-retest reliability coefficients were found to be over 0.70 and thus acceptable. The first items on the scale were about demographical information including age, race,
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and gender. The next two items asked the students about previous exposure to physical activity and nutrition programs taught in school; four choices were provided including none, one, two, and three or more class lessons. In the next five items, students were asked to do a 24-hour recall for the four behaviors. Students were asked to write the exact amount of time in minutes they exercised or participated in physical activity at home, the number of hours they spent watching TV, the number of glasses of water drank, and the number of fruits and vegetables eaten. The next 16 items were about anticipatory outcomes/outcome expectations of physical activity, watching less TV, drinking water, and eating fruits and vegetables. The scale provided five choices on a 0-4 scale, where 0 = never, 1 = hardly ever, 2 = sometimes, 3 = almost always, and 4 = always. Physical activity items for anticipatory outcomes/outcome expectations included not getting sick as often, having more confidence, having more fun, and looking better. Items for watching less TV included having more friends, having more free time, having more fun, and being more relaxed. Items for drinking water included being more relaxed, feeling better, having more energy, and having better weight. Items for eating fruits and vegetables included having more energy, feeling better, not getting sick as often, and having better weight. The next 10 items corresponded to the importance the child places on each of the anticipatory outcomes/outcome expectation items; these are called as outcome expectancies. The scale provided five choices on a 0-4 scale, where 0 = not important at all, 1 = slightly important, 2 = moderately important, 3 = very important, and 4 = extremely important. The outcome expectations were multiplied with corresponding outcome expectancies to derive expectation scores for all behaviors. The last 20 items were designed around the four behaviors and presented in sets of five items—one set per behavior. The scale provided five choices, including not at all sure (0), slightly sure (1), moderately sure (2), very sure (3), and completely sure (4). The first item in each set was about self-efficacy to perform the behavior, the second and third items were about self-efficacy in overcoming challenges that are presented while performing the behavior, the fourth item was about self-control as measured by the child’s ability to set goals to perform the behavior, and the last item was also about self-control as measured by the child’s ability to self-reward for performing the behavior. Data Collection Data were collected between May and June 2013. Institutional Review Board (IRB) permission from the parent University was obtained before initiating the study. Permission was also obtained from principals of the schools before distributing parental permission slips. Parent permission was also obtained. Child assent was obtained through an age appropriate brief write-up, which was
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presented before beginning the instrument. Inclusion criteria for participation in the study included being a 4th through 6th grade student, being identified as African American, having permission from a parent, and giving child assent. Data Analyses All data were analyzed by the Statistical Package for Social Sciences (SPSS), Version 19.0. Descriptive statistics were computed for all the variables. Stepwise multiple regression was to model the predictors for each of the four behaviors. The a priori criteria of probability of F to enter the predictor in the model was chosen as less than and equal to 0.05, and for removing the predictor as greater than and equal to 0.10. The predictors used in the model included age, gender, number of times taught about healthy eating in school, number of times taught at school to do physical activity or exercise at home, expectations for performing each of the four behaviors, and self-efficacy and self-control to perform each of the four behaviors. RESULTS The scale was administered to 222 students in grades 4th through 6th. Some students were eliminated from data analysis if they had given unrealistic answers (such as watching TV for 24 hours or drinking 100 glasses of water), if they did not identify themselves as African American, or if they had large amounts of missing information, which constitutes as an incomplete survey. A total of 14 students met the criteria for elimination; therefore only 208 students were used in the data analysis. The ages of the respondents ranged from 9 to 13 years old. The majority of the respondents (69; 33.2%), were 11 years old, 68 (32.7%) were 10 year olds, 48 (23.1%) were 12 year olds, 16 (7.7%) were 9 years old, and 7 (3.4%) were 13 years old. There was an equal amount of male (104; 50%) and female (104; 50%) participants. All of the participants identified themselves as African American (208; 100%). More than half of the students (53.4%) had been exposed to three or more sessions about healthy eating in school, 51 (24.5%) to two sessions, 35 (16.8%) to one session, and 9 (4.3%) had not been exposed to any sessions about healthy eating in school. One hundred and twenty-six (60.6%) of the students had been exposed to three or more sessions in school about engaging in physical activity or exercise at home, 44 (21.2%) to two sessions, 25 (12%) to one session, and 10 (4.8%) had not been exposed to any sessions in school about engaging in physical activity or exercise at home. Table 1 presents descriptive statistics about the four behaviors including minutes of daily moderately intense physical activity, number of hours of TV watching, number of glasses of water per day, and number of cups of fruits and vegetable consumed per day. The average number of minutes exercised was above the recommended total of 60 minutes of daily physical activity. The other
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Table 1. Means and Standard Deviations of Number of Minutes Exercised at Home, Number of Hours of TV Watched, Glasses of Water Consumed, and Number of Servings of Fruits and Vegetables Eaten in Past 24 Hours n
Minimum Maximum Mean
SD
Number of minutes exercised at home in past 24 hours
202
0
360
73.72
82.47
Number of hours watched TV in past 24 hours
191
0
10
2.58
2.38
Number of glasses of water consumed in past 24 hours
198
0
15
4.33
3.19
Number of servings of fruits eaten in past 24 hours
202
0
10
2.47
2.17
Number of servings of vegetables eaten in past 24 hours
200
0
10
1.83
1.99
Number of fruits and vegetables eaten in past 24 hours
200
0
15
4.27
3.18
average values were below the recommendations for number of glasses of water consumed per day, and number of fruits and vegetables consumed per day. The number of hours of TV watching was above the recommended level of 2 hours per day. Table 2 presents means and standard deviations of the constructs of social cognitive theory, which includes: expectations for engaging in each behavior, self-efficacy to perform each behavior, and self-control to perform each behavior. The means for the constructs of social cognitive theory for the four behaviors were all in the middle of the possible range of values. For physical activity and television watching one of the social cognitive theory constructs or other variables were predictive. Table 3 summarizes the parameter estimates from the stepwise regression of number of glasses of water drank. The two significant predictors for drinking water were self-control for drinking water and self-efficacy for drinking water and the two together accounted for approximately 12.3% of the variance. Table 4 summarizes the parameter estimates from the stepwise regression of the number of fruits and vegetables eaten. The significant predictor was self-efficacy for eating fruits and vegetables, which accounts for 8.3% of the variance.
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Table 2. Means and Standard Deviations of Scores of Social Cognitive Theory Constructs for the Four Behaviors n
Minimum Maximum Mean
SD
Expectations for exercising 30 min daily
198
0
64
28.79
13.75
Self-efficacy for exercising 30 min daily
206
0
12
6.93
3.08
Self-control to set goals for exercising 30 min daily
203
0
8
5.73
2.09
Expectations for watching less than 2 hours of TV daily
194
0
64
27.24
16.03
Self-efficacy for watching less than 2 hours of TV daily
198
0
12
6.30
3.43
Self-control for restricting TV watching to less than 2 hours daily
203
0
8
4.78
2.67
Expectations for drinking 8 or more glasses of water per day
199
0
64
37.63
16.27
Self-efficacy for drinking 8 glasses of water per day
202
0
12
8.63
3.23
Self-control for drinking 8 glasses of water per day
207
0
8
5.09
2.36
Expectations for eating five or more servings of fruits and vegetables daily
203
0
64
35.93
16.42
Self-efficacy for eating five or more servings of fruits and vegetables daily
206
0
12
7.82
3.39
Self-control for eating five or more servings of fruits and vegetables daily
206
0
8
5.77
2.19
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Table 3. Parameter Estimates from the Final Regression Model for Number of Glasses of Water Consumed in the Past 24 Hours as Predicted by Self-Efficacy for Drinking Water and Self-Control for Drinking Water (Adjusted R2 = 0.123) Unstandardized coefficients B
Std. error
1.293
.626
Self-control for drinking water
.298
.117
.226
2.546
.012
Self-efficacy for drinking water
.169
.084
.177
1.996
.047
(Constant)
Standardized coefficients Beta
t
p-Value
2.067
Table 4. Parameter Estimates from the Final Regression Model for Fruits and Vegetables Consumed in the Past 24 Hours as Predicted by Self-Efficacy for Eating Fruits and Vegetables (Adjusted R2 = 0.083)
(Constant) Self-efficacy for eating fruits and vegetables
Unstandardized coefficients B
Std. error
1.933
.623
.311
.073
Standardized coefficients Beta
.296
t
p-Value
3.104
.002
4.246
.000
DISCUSSION The purpose of this study was to examine the extent to which selected social cognitive theory constructs (self-efficacy, self-control, and expectations) can predict the four behaviors of daily moderately intense physical activity for at least 60 minutes per day, limiting television viewing, increasing fruit and vegetable intake to five or more cups per day, and increasing water consumption in upper elementary African-American children. Results of the study found that only two of the constructs were significant predictors in two of the four behaviors.
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In the case of drinking water, self-control for drinking water (p < 0.012) and self-efficacy for drinking water (p < 0.047) were significant predictors. These are two important constructs of social cognitive theory and emphasize the need for building behavior specific confidence and self-control to modify water drinking behavior in African-American children. These findings are different from the findings done in a study with predominantly White children in which the significant construct was expectations [10]. Perhaps for African-American children the constructs of self-efficacy and self-control are more important. To our knowledge there was no specific intervention for the target population that was implemented prior to the study that modified these two constructs. So the level of this behavior seems to be what would be expected in this population. The mean number of glasses of water consumed in a day was 4.33, which is less than the recommendation of eight or more glasses of water per day. In regard to increasing water consumption among upper elementary African-American students, there is a need for health education interventions. These interventions can be based on social cognitive theory. In the case of eating fruits and vegetables, self-efficacy for eating fruits and vegetables was the only significant predictor (p < 0.001). The other two constructs of self-control and expectations were not found to be significant predictors. These findings are similar to the findings done in a study with predominantly White children also in which the significant construct was self-efficacy [10]. The most important construct in social cognitive theory is claimed to be self-efficacy and this study is indicating that assertion. Children usually eat foods based on their liking of the taste, appearance, and ease. All these are important in building self-efficacy toward fruits and vegetables. The mean number of fruits and vegetables consumed for the sample population was 4.27, which is slightly below the recommendation of 5 or more servings of fruits and vegetables per day. This finding is particularly encouraging as it shows that a greater number of African-American children are eating fruits and vegetables. In the case of physical activity there were no significant predictors. The mean score of physical activity was 73.72 minutes, which is more than the recommendation of 60 minutes per day. These findings are different from the findings done in a study with predominantly White children in whom the significant constructs were self-efficacy and number of times taught in school [10]. In this study we had selected only the personal level constructs of social cognitive theory and did not reify environmental constructs. For African-American children the constructs of environment and situational perception are also important. Future studies must focus on these constructs. In the case of watching television there also were no significant predictors. These findings are different from the findings done in a study with predominantly White children in whom the significant constructs were self-control and number of times taught in school [10]. Once again, in this study we had selected only the personal level constructs of social cognitive theory and did not reify
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environmental constructs. For African-American children, the constructs of environment and situational perception are also important. The students in these particular groups may not have access to a TV or cable, which in turn prevents them from watching more TV. There were some limitations to this study. First, random selection of subjects was not used in this study; this introduces the possibility of sampling bias. Second, to measure primary dependent variables participants were asked to do a 24-hour recall. While this method increases accuracy, student’s answers may not represent a typical day for the participant. Third, self-report was used for the entire instrument, this introduces measurement bias. However, to decrease measurement bias and account for varying levels of readability, the instrument was read to the participants. Finally, nothing can be discussed about the temporality of association, because the study was cross-sectional in nature. IMPLICATIONS FOR PRACTICE According to the results of the study it is apparent that more health promotion and education programs need to be targeted specifically to African-American children. An increase in programs that promote limiting television viewing, encouraging daily physical activity, increasing fruit and vegetable intake, and increasing water consumption also need to be implemented in the AfricanAmerican community. Social cognitive theory offers an excellent framework to design such programs and interventions for African-American youth. In order to build expectations, the benefits of these behaviors must be highlighted. For developing self-efficacy, breaking down each behavior into small steps, using role models, reducing stress, and using persuasion must be utilized. For building self-control, goal setting and self-rewards are helpful. Interventions can be implemented by health and physical education teachers. REFERENCES 1. C. L. Ogden, M. D. Carroll, L. R. Curtin, M. M. Lamb, and K. M. Flegal, Prevalence of High Body Mass Index in U.S. Children and Adolescents, 2007-2008, Journal of the American Medical Association, 303:3, pp. 242-249, 2010. 2. United States Department of Health and Human Services (USDHHS), Healthy People 2020: Nutrition, Physical Activity, and Obesity, 2013. Available at http://healthy people.gov/2020/lhi/nutrition.aspx?tab=data 3. C. L. Ogden, M. D. Carroll, B. K. Kit, and K. M. Flegal, Prevalence of Obesity and Trends in Body Mass Index among US Children and Adolescents, 1999-2010. Journal of the American Medical Association, 307:5, pp. 483-490, 2012. 4. M. J. Ickes and M. Sharma, A Review of Childhood Obesity Prevention Interventions Targeting African American Children, Vulnerable Children and Youth Studies, 6:2, pp. 103-123, 2011.
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5. E. A. Finkelstein, J. G. Trogdon, J. W. Cohen, and W. Dietz, Annual Medical Spending Attributable to Obesity: Payer- and Service-Specific Estimates, Health Affairs, 28:5, pp. w822-w831, 2009. 6. S. Sekhar, The Significance of Childhood Obesity in Communities of Color, Center for American Progress, 2010. Available at http://www.americanprogress.org/ issues/healthcare/report/2010/06/14/7908/the-significance-of-childhood-obesity-incommunities-of-color/ 7. W. H. Dietz, Health Consequences of Obesity in Youth: Childhood Predictors of Adult Disease, Pediatrics, 101, pp. 518-525, 1998. 8. Centers for Disease Control and Prevention, Black or African American populations, July 2013. Available at http://www.cdc.gov/minorityhealth/populations/ REMP/black.html 9. D. F. Polit and B. P. Hungler, Nursing Research. Principles and Methods, Lippincott Williams & Wilkins, Philadelphia, 1999. 10. M. Sharma, D. Wagner, and J. Wilkerson, Predicting Childhood Obesity Prevention Behaviors Using Social Cognitive Theory, International Quarterly of Community Health Education, 24:3, pp. 191-203, 2005.
Direct reprint requests to: Manoj Sharma, MBBS, MCHES, Ph.D., FAAHB Professor, Health Promotion & Education University of Cincinnati P.O. Box 210068 Cincinnati, OH 45221-0068 e-mail: [email protected]
SHAKEYRAH ELMORE MANOJ SHARMA, MBBS, MCHES, PH.D. University of Cincinnati, Ohio
ABSTRACT
Childhood obesity is a major public health problem in the African-American community. Commonly suggested public health strategies to reduce childhood obesity are limiting television viewing, encouraging daily moderately intense physical activity of at least 60 minutes per day, increasing fruit and vegetable intake to five or more cups per day, and increasing water consumption. This study examined the extent to which selected social cognitive theory constructs can predict these four behaviors in African-American upper elementary children. A 56-item valid and reliable scale was administered to 222 students. Glasses of water consumed were predicted by self-control for drinking water and self-efficacy for drinking water (R2 = 0.123). Fruits and vegetables consumed were predicted by self-efficacy for eating fruits and vegetables (R2 = 0.083). For designing primary prevention interventions to reduce childhood obesity in the African-American community, social cognitive theory provides a useful framework.
Int’l. Quarterly of Community Health Education, Vol. 34(2) 187-197, 2013-2014 Ó 2014, Baywood Publishing Co., Inc. doi: http://dx.doi.org/10.2190/IQ.34.2.f http://baywood.com 187
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INTRODUCTION Childhood obesity is a major public health concern for the United States. Childhood obesity has tripled since 1980 [1]. African Americans are disproportionally affected by overweight and obesity. Healthy People 2020 estimates that the rate for the black non-Hispanic population is more than one-and-a-half times the rate for their white non-Hispanic counterparts [2]. Childhood obesity among African-American children ages 2-19 is 35.9% [3]. Obesity has a negative and deleterious impact on the physical, social, behavioral, and psychological health of children [4]. It is estimated that the national healthcare expenditures related to overweight and obesity has increased by 68.5 billion dollars from 1998 to 2008 to about 147 billion dollars [5]. Therefore, government initiatives and resources to promote reduction of childhood obesity implemented at the primary level of prevention is an increasing trend. There have also been a substantial number of research studies conducted that have focused on obesity in children. Provisions in the Patient Protection and Affordable Care Act, the First Lady’s Let’s Move initiative, and the recommendations of the Presidential Task Force on Childhood Obesity offers a strong foundation for creating broader initiatives to reduce childhood obesity, but they seldom specifically address racial and ethnic disparities in obesity [6]. It is evident that more successful health education programs need to be implemented, particularly in the African-American community that addresses ethic and cultural differences. The development of obesity in the African-American community is due to a number of influences, including genetic factors and cultural differences, such as those related to diet and social norms, which include the acceptance of surplus weight [4]. Overweight and obesity are likely to persist into adulthood; children who are overweight or obese are more likely than their normal weight counterparts to be overweight or obese as adults. This increases the likelihood of adult diseases [7]. Three of the four top leading causes of death in the African-American community as determined by the Centers for Disease Control and Prevention (CDC) provide obesity, physical inactivity, and diet as risk factors [8]. African Americans who are overweight or obese are more likely to have high cholesterol and high blood pressure, and other factors that increase the risk for heart disease and stroke— which are the top two leading causes of death in the African-American community—and diabetes—which is the 4th leading cause of death in the population [8]. The health disparities which exist in the African-American community are important especially in children, because they have less control over factors that are considered risk factors for obesity, for example environment or socioeconomic status. There is also a lack of research literature related to childhood obesity focusing specifically on African-American children. Social cognitive theory provides a useful framework for designing primary prevention interventions to reduce childhood obesity in African Americans. The
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major personal level constructs of social cognitive theory include self-efficacy, self-control, and expectations. In approaching behavior change, self-efficacy is an important requirement. Self-efficacy describes a person’s confidence in completing a particular behavior at a given moment. Self-control describes a person’s capability to regulate their behavior. Self-control includes strategies which encourage proximal and distal goal-setting and self-rewards. Expectations are the anticipation of the outcome of a particular behavior and the value one places on those outcomes. Different types of expectations include physical outcomes, social outcomes which include approval and disapproval, and self-evaluated positive and negative reactions. Therefore, the purpose of the study was to examine the extent to which social cognitive constructs (self-efficacy, selfcontrol, and expectations) can predict the four behaviors of limiting television viewing, performing daily moderately intense physical activity of at least 60 minutes per day, increasing fruit and vegetable intake to five or more cups per day, and increasing water consumption in upper elementary AfricanAmerican children. METHODS Population and Sample The sample population consisted of 4th through 6th grade African-American students. There were 222 students who participated in the study. The sample population came from three public schools in two large Midwestern cities. In calculating sample size, power was set at 0.80 and alpha was set at 0.05, based on previous studies population correlation coefficient was assumed to be 0.20 and that yielded a sample size of 197 [9]. An approximate 10% inflation to the sample was done to account for missing values. Design The design for the study was cross sectional. The dependent variables were the four behaviors and the independent variables for each behavior were the three constructs of social cognitive theory (self-efficacy, self-control, and expectations) along with gender, age, and whether they had been taught about physical activity and nutrition in school. Instrumentation A 56-item scale was developed and validated in a previous study in a two-round process by a panel of six experts, which included three university professionals and three experts from the school system [10]. Cronbach’s alpha and test-retest reliability coefficients were found to be over 0.70 and thus acceptable. The first items on the scale were about demographical information including age, race,
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and gender. The next two items asked the students about previous exposure to physical activity and nutrition programs taught in school; four choices were provided including none, one, two, and three or more class lessons. In the next five items, students were asked to do a 24-hour recall for the four behaviors. Students were asked to write the exact amount of time in minutes they exercised or participated in physical activity at home, the number of hours they spent watching TV, the number of glasses of water drank, and the number of fruits and vegetables eaten. The next 16 items were about anticipatory outcomes/outcome expectations of physical activity, watching less TV, drinking water, and eating fruits and vegetables. The scale provided five choices on a 0-4 scale, where 0 = never, 1 = hardly ever, 2 = sometimes, 3 = almost always, and 4 = always. Physical activity items for anticipatory outcomes/outcome expectations included not getting sick as often, having more confidence, having more fun, and looking better. Items for watching less TV included having more friends, having more free time, having more fun, and being more relaxed. Items for drinking water included being more relaxed, feeling better, having more energy, and having better weight. Items for eating fruits and vegetables included having more energy, feeling better, not getting sick as often, and having better weight. The next 10 items corresponded to the importance the child places on each of the anticipatory outcomes/outcome expectation items; these are called as outcome expectancies. The scale provided five choices on a 0-4 scale, where 0 = not important at all, 1 = slightly important, 2 = moderately important, 3 = very important, and 4 = extremely important. The outcome expectations were multiplied with corresponding outcome expectancies to derive expectation scores for all behaviors. The last 20 items were designed around the four behaviors and presented in sets of five items—one set per behavior. The scale provided five choices, including not at all sure (0), slightly sure (1), moderately sure (2), very sure (3), and completely sure (4). The first item in each set was about self-efficacy to perform the behavior, the second and third items were about self-efficacy in overcoming challenges that are presented while performing the behavior, the fourth item was about self-control as measured by the child’s ability to set goals to perform the behavior, and the last item was also about self-control as measured by the child’s ability to self-reward for performing the behavior. Data Collection Data were collected between May and June 2013. Institutional Review Board (IRB) permission from the parent University was obtained before initiating the study. Permission was also obtained from principals of the schools before distributing parental permission slips. Parent permission was also obtained. Child assent was obtained through an age appropriate brief write-up, which was
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presented before beginning the instrument. Inclusion criteria for participation in the study included being a 4th through 6th grade student, being identified as African American, having permission from a parent, and giving child assent. Data Analyses All data were analyzed by the Statistical Package for Social Sciences (SPSS), Version 19.0. Descriptive statistics were computed for all the variables. Stepwise multiple regression was to model the predictors for each of the four behaviors. The a priori criteria of probability of F to enter the predictor in the model was chosen as less than and equal to 0.05, and for removing the predictor as greater than and equal to 0.10. The predictors used in the model included age, gender, number of times taught about healthy eating in school, number of times taught at school to do physical activity or exercise at home, expectations for performing each of the four behaviors, and self-efficacy and self-control to perform each of the four behaviors. RESULTS The scale was administered to 222 students in grades 4th through 6th. Some students were eliminated from data analysis if they had given unrealistic answers (such as watching TV for 24 hours or drinking 100 glasses of water), if they did not identify themselves as African American, or if they had large amounts of missing information, which constitutes as an incomplete survey. A total of 14 students met the criteria for elimination; therefore only 208 students were used in the data analysis. The ages of the respondents ranged from 9 to 13 years old. The majority of the respondents (69; 33.2%), were 11 years old, 68 (32.7%) were 10 year olds, 48 (23.1%) were 12 year olds, 16 (7.7%) were 9 years old, and 7 (3.4%) were 13 years old. There was an equal amount of male (104; 50%) and female (104; 50%) participants. All of the participants identified themselves as African American (208; 100%). More than half of the students (53.4%) had been exposed to three or more sessions about healthy eating in school, 51 (24.5%) to two sessions, 35 (16.8%) to one session, and 9 (4.3%) had not been exposed to any sessions about healthy eating in school. One hundred and twenty-six (60.6%) of the students had been exposed to three or more sessions in school about engaging in physical activity or exercise at home, 44 (21.2%) to two sessions, 25 (12%) to one session, and 10 (4.8%) had not been exposed to any sessions in school about engaging in physical activity or exercise at home. Table 1 presents descriptive statistics about the four behaviors including minutes of daily moderately intense physical activity, number of hours of TV watching, number of glasses of water per day, and number of cups of fruits and vegetable consumed per day. The average number of minutes exercised was above the recommended total of 60 minutes of daily physical activity. The other
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Table 1. Means and Standard Deviations of Number of Minutes Exercised at Home, Number of Hours of TV Watched, Glasses of Water Consumed, and Number of Servings of Fruits and Vegetables Eaten in Past 24 Hours n
Minimum Maximum Mean
SD
Number of minutes exercised at home in past 24 hours
202
0
360
73.72
82.47
Number of hours watched TV in past 24 hours
191
0
10
2.58
2.38
Number of glasses of water consumed in past 24 hours
198
0
15
4.33
3.19
Number of servings of fruits eaten in past 24 hours
202
0
10
2.47
2.17
Number of servings of vegetables eaten in past 24 hours
200
0
10
1.83
1.99
Number of fruits and vegetables eaten in past 24 hours
200
0
15
4.27
3.18
average values were below the recommendations for number of glasses of water consumed per day, and number of fruits and vegetables consumed per day. The number of hours of TV watching was above the recommended level of 2 hours per day. Table 2 presents means and standard deviations of the constructs of social cognitive theory, which includes: expectations for engaging in each behavior, self-efficacy to perform each behavior, and self-control to perform each behavior. The means for the constructs of social cognitive theory for the four behaviors were all in the middle of the possible range of values. For physical activity and television watching one of the social cognitive theory constructs or other variables were predictive. Table 3 summarizes the parameter estimates from the stepwise regression of number of glasses of water drank. The two significant predictors for drinking water were self-control for drinking water and self-efficacy for drinking water and the two together accounted for approximately 12.3% of the variance. Table 4 summarizes the parameter estimates from the stepwise regression of the number of fruits and vegetables eaten. The significant predictor was self-efficacy for eating fruits and vegetables, which accounts for 8.3% of the variance.
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Table 2. Means and Standard Deviations of Scores of Social Cognitive Theory Constructs for the Four Behaviors n
Minimum Maximum Mean
SD
Expectations for exercising 30 min daily
198
0
64
28.79
13.75
Self-efficacy for exercising 30 min daily
206
0
12
6.93
3.08
Self-control to set goals for exercising 30 min daily
203
0
8
5.73
2.09
Expectations for watching less than 2 hours of TV daily
194
0
64
27.24
16.03
Self-efficacy for watching less than 2 hours of TV daily
198
0
12
6.30
3.43
Self-control for restricting TV watching to less than 2 hours daily
203
0
8
4.78
2.67
Expectations for drinking 8 or more glasses of water per day
199
0
64
37.63
16.27
Self-efficacy for drinking 8 glasses of water per day
202
0
12
8.63
3.23
Self-control for drinking 8 glasses of water per day
207
0
8
5.09
2.36
Expectations for eating five or more servings of fruits and vegetables daily
203
0
64
35.93
16.42
Self-efficacy for eating five or more servings of fruits and vegetables daily
206
0
12
7.82
3.39
Self-control for eating five or more servings of fruits and vegetables daily
206
0
8
5.77
2.19
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Table 3. Parameter Estimates from the Final Regression Model for Number of Glasses of Water Consumed in the Past 24 Hours as Predicted by Self-Efficacy for Drinking Water and Self-Control for Drinking Water (Adjusted R2 = 0.123) Unstandardized coefficients B
Std. error
1.293
.626
Self-control for drinking water
.298
.117
.226
2.546
.012
Self-efficacy for drinking water
.169
.084
.177
1.996
.047
(Constant)
Standardized coefficients Beta
t
p-Value
2.067
Table 4. Parameter Estimates from the Final Regression Model for Fruits and Vegetables Consumed in the Past 24 Hours as Predicted by Self-Efficacy for Eating Fruits and Vegetables (Adjusted R2 = 0.083)
(Constant) Self-efficacy for eating fruits and vegetables
Unstandardized coefficients B
Std. error
1.933
.623
.311
.073
Standardized coefficients Beta
.296
t
p-Value
3.104
.002
4.246
.000
DISCUSSION The purpose of this study was to examine the extent to which selected social cognitive theory constructs (self-efficacy, self-control, and expectations) can predict the four behaviors of daily moderately intense physical activity for at least 60 minutes per day, limiting television viewing, increasing fruit and vegetable intake to five or more cups per day, and increasing water consumption in upper elementary African-American children. Results of the study found that only two of the constructs were significant predictors in two of the four behaviors.
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In the case of drinking water, self-control for drinking water (p < 0.012) and self-efficacy for drinking water (p < 0.047) were significant predictors. These are two important constructs of social cognitive theory and emphasize the need for building behavior specific confidence and self-control to modify water drinking behavior in African-American children. These findings are different from the findings done in a study with predominantly White children in which the significant construct was expectations [10]. Perhaps for African-American children the constructs of self-efficacy and self-control are more important. To our knowledge there was no specific intervention for the target population that was implemented prior to the study that modified these two constructs. So the level of this behavior seems to be what would be expected in this population. The mean number of glasses of water consumed in a day was 4.33, which is less than the recommendation of eight or more glasses of water per day. In regard to increasing water consumption among upper elementary African-American students, there is a need for health education interventions. These interventions can be based on social cognitive theory. In the case of eating fruits and vegetables, self-efficacy for eating fruits and vegetables was the only significant predictor (p < 0.001). The other two constructs of self-control and expectations were not found to be significant predictors. These findings are similar to the findings done in a study with predominantly White children also in which the significant construct was self-efficacy [10]. The most important construct in social cognitive theory is claimed to be self-efficacy and this study is indicating that assertion. Children usually eat foods based on their liking of the taste, appearance, and ease. All these are important in building self-efficacy toward fruits and vegetables. The mean number of fruits and vegetables consumed for the sample population was 4.27, which is slightly below the recommendation of 5 or more servings of fruits and vegetables per day. This finding is particularly encouraging as it shows that a greater number of African-American children are eating fruits and vegetables. In the case of physical activity there were no significant predictors. The mean score of physical activity was 73.72 minutes, which is more than the recommendation of 60 minutes per day. These findings are different from the findings done in a study with predominantly White children in whom the significant constructs were self-efficacy and number of times taught in school [10]. In this study we had selected only the personal level constructs of social cognitive theory and did not reify environmental constructs. For African-American children the constructs of environment and situational perception are also important. Future studies must focus on these constructs. In the case of watching television there also were no significant predictors. These findings are different from the findings done in a study with predominantly White children in whom the significant constructs were self-control and number of times taught in school [10]. Once again, in this study we had selected only the personal level constructs of social cognitive theory and did not reify
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environmental constructs. For African-American children, the constructs of environment and situational perception are also important. The students in these particular groups may not have access to a TV or cable, which in turn prevents them from watching more TV. There were some limitations to this study. First, random selection of subjects was not used in this study; this introduces the possibility of sampling bias. Second, to measure primary dependent variables participants were asked to do a 24-hour recall. While this method increases accuracy, student’s answers may not represent a typical day for the participant. Third, self-report was used for the entire instrument, this introduces measurement bias. However, to decrease measurement bias and account for varying levels of readability, the instrument was read to the participants. Finally, nothing can be discussed about the temporality of association, because the study was cross-sectional in nature. IMPLICATIONS FOR PRACTICE According to the results of the study it is apparent that more health promotion and education programs need to be targeted specifically to African-American children. An increase in programs that promote limiting television viewing, encouraging daily physical activity, increasing fruit and vegetable intake, and increasing water consumption also need to be implemented in the AfricanAmerican community. Social cognitive theory offers an excellent framework to design such programs and interventions for African-American youth. In order to build expectations, the benefits of these behaviors must be highlighted. For developing self-efficacy, breaking down each behavior into small steps, using role models, reducing stress, and using persuasion must be utilized. For building self-control, goal setting and self-rewards are helpful. Interventions can be implemented by health and physical education teachers. REFERENCES 1. C. L. Ogden, M. D. Carroll, L. R. Curtin, M. M. Lamb, and K. M. Flegal, Prevalence of High Body Mass Index in U.S. Children and Adolescents, 2007-2008, Journal of the American Medical Association, 303:3, pp. 242-249, 2010. 2. United States Department of Health and Human Services (USDHHS), Healthy People 2020: Nutrition, Physical Activity, and Obesity, 2013. Available at http://healthy people.gov/2020/lhi/nutrition.aspx?tab=data 3. C. L. Ogden, M. D. Carroll, B. K. Kit, and K. M. Flegal, Prevalence of Obesity and Trends in Body Mass Index among US Children and Adolescents, 1999-2010. Journal of the American Medical Association, 307:5, pp. 483-490, 2012. 4. M. J. Ickes and M. Sharma, A Review of Childhood Obesity Prevention Interventions Targeting African American Children, Vulnerable Children and Youth Studies, 6:2, pp. 103-123, 2011.
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5. E. A. Finkelstein, J. G. Trogdon, J. W. Cohen, and W. Dietz, Annual Medical Spending Attributable to Obesity: Payer- and Service-Specific Estimates, Health Affairs, 28:5, pp. w822-w831, 2009. 6. S. Sekhar, The Significance of Childhood Obesity in Communities of Color, Center for American Progress, 2010. Available at http://www.americanprogress.org/ issues/healthcare/report/2010/06/14/7908/the-significance-of-childhood-obesity-incommunities-of-color/ 7. W. H. Dietz, Health Consequences of Obesity in Youth: Childhood Predictors of Adult Disease, Pediatrics, 101, pp. 518-525, 1998. 8. Centers for Disease Control and Prevention, Black or African American populations, July 2013. Available at http://www.cdc.gov/minorityhealth/populations/ REMP/black.html 9. D. F. Polit and B. P. Hungler, Nursing Research. Principles and Methods, Lippincott Williams & Wilkins, Philadelphia, 1999. 10. M. Sharma, D. Wagner, and J. Wilkerson, Predicting Childhood Obesity Prevention Behaviors Using Social Cognitive Theory, International Quarterly of Community Health Education, 24:3, pp. 191-203, 2005.
Direct reprint requests to: Manoj Sharma, MBBS, MCHES, Ph.D., FAAHB Professor, Health Promotion & Education University of Cincinnati P.O. Box 210068 Cincinnati, OH 45221-0068 e-mail: [email protected]
