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Unhealthy behaviors and psychosocial difficulties among overweight adolescents: the potential impact of familial factors
JOURNAL OF ADOLESCENT HEALTH 2002;31:145–153
ORIGINAL ARTICLE
Unhealthy Behaviors and Psychosocial Difficulties Among Overweight Adolescents: The Potential Impact of Familial Factors ALISON E. MELLIN, Ph.D., DIANNE NEUMARK-SZTAINER, Ph.D., M.P.H., R.D., MARY STORY, Ph.D. R.D., MARJORIE IRELAND, Ph.D., AND MICHAEL D. RESNICK, Ph.D.
Purpose: To compare overweight and non-overweight youth on a selection of self-reported eating, physical activity, dieting, educational, and emotional variables and identify familial factors that serve as protective forces against unhealthy behaviors and psychosocial difficulties among overweight adolescents. Methods: Data were taken from a 1996 cross-sectional school-based survey of 9957 adolescents in grades 7, 9, and 11. Based on self-reported heights and weights, respondents were categorized as “overweight” (body mass index) >85th percentile or “non-overweight.” Student’s t-tests were used to compare the non-overweight and overweight sample on the self-reported health-related behaviors and psychosocial variables. Logistic and linear regressions were used to identify familial factors associated with a reduced risk of engaging in unhealthy behaviors and experiencing psychosocial distress. Results: Overweight adolescents reported engaging in significantly more unhealthy behaviors and experiencing more psychosocial distress than their non-overweight peers. Among the overweight youth, higher levels of reported family connectedness and parental expectations and moderate levels of parental monitoring were associated with the lowest levels of unhealthy behaviors and psychosocial distress. Conclusions: Satisfying and developmentally appropriate parent-adolescent relationships are associated From the Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis, Minnesota (A.E.M., D.N.-S., M.S.); and Division of General Pediatrics and Adolescent Health, University of Minnesota, Minneapolis, Minnesota (M.I., M.D.R.). Address correspondence to: Alison Mellin, Ph.D., Division of Epidemiology, University of Minnesota School of Public Health, Suite 300, 1300 South Second Street, Minneapolis, Minnesota 55454-1015. E-mail: [email protected]. Manuscript accepted October 15, 2001.
with reduced behavioral and psychosocial risk factors associated with overweight during adolescence. © Society for Adolescent Medicine, 2002
KEY WORDS:
Adolescence Family Obesity Overweight Protective factors
Being an overweight adolescent in the United States is becoming increasingly common. Data from the most recent National Health and Nutrition Examination Survey (NHANES III, 1988 –1991) indicate that approximately 22% of adolescents are overweight [1]. Despite the increasing numbers of overweight youth, this group continues to experience stigmatization and discrimination as well as pressure to be thin from the media, their peers, and even health care professionals [2– 6]. Researchers hypothesize that weight discrimination, presence of negative stereotypes, and pressure to conform to an unattainable ideal body shape may be some of the reasons overweight youth are at risk for certain unhealthy behaviors and adverse psychological, social, and economic outcomes. Behavioral correlates of overweight in teenagers include more time in sedentary activities (e.g. television watching), less time in physical activities, and higher consumption of high fat/high sugar foods [7–9]. Overweight adolescent girls are also more
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likely to engage in unhealthy dieting behaviors including skipping meals and binge eating [10]. Overweight during adolescence has also been linked, albeit inconsistently, with lower self-esteem, lower self-concept, and higher rates of psychosocial difficulties [11–14]. In the face of social pressure to be thin, however, there are many overweight adolescents who do not experience psychosocial problems [5,10,11,15]. What could explain the variability in psychosocial functioning among overweight youth? To answer this question, research has examined the impact of familial factors on overweight youth. Bruch [16] studied obese individuals from childhood through adulthood and found a wide variation among individuals in self-concept and psychosocial well-being. Bruch accounted for a large portion of the variation in psychological functioning to the obese child’s family; children in supportive and accepting families fared better in both psychological adjustment and weight management than children who were in a family in which they were admonished for their weight and whose familial relationships were characterized as dysfunctional. Epstein et al. [17] also examined familial correlates of psychological problems in obese children and found that among moderately obese children seeking treatment, parental psychopathology had the strongest relationship with child psychosocial problems, even stronger than the child’s body mass index (BMI). Research on risk and protective factors indicates that family context variables have a strong association with the emotional well-being of adolescents and their health-related behaviors [18 –22]. To date, there is little research examining the impact of family connectedness, parental expectations, and parental monitoring on the health-related behaviors and psychosocial well-being of overweight adolescents. The purpose of this study was to: (a) compare overweight and non-overweight adolescents on selected nutrition, physical activity, and dieting behaviors and psychosocial well-being variables, and (b) examine the association of selected family factors with health-related behaviors and psychosocial variables among overweight adolescents.
Methods Study Population The study population included a representative sampling of 7th, 9th, and 11th grade public school students (N ⫽ 9957) from Connecticut who partici-
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Table 1. Ethnicity of Total Sample Population and Subsample of Overweight Youth
Ethnicity
Total Study Population (%) (n ⫽ 9024)
Overweight Subsample (%) (n ⫽ 1829)
White African-American Hispanic/Latino Asian/Pacific Islander American Indian Multiracial
74.0 8.9 6.9 2.5 0.7 7.0
64.0 13.7 10.1 1.8 0.9 9.1
pated in a statewide survey of adolescent health from 1995 to 1996 [23]. BMI (weight in kilograms/ height in meters squared) was calculated from selfreported weight and height measurements. The 839 youth who did not self-report their height or weight or who had a spuriously high (⬎50) or extremely low BMI (⬍10) were excluded from the study, resulting in a sample of 9118 for analysis. Adolescents with a BMI equal to or above the 85th percentile were classified as overweight [24]. Of females, 15% (n ⫽ 692), and of males, 26% (n ⫽ 1157) were categorized as overweight. The mean age of the entire sample was 14.4 (SD ⫽ 2.88) years with no significant differences in age between the nonoverweight and overweight groups. The mean socioeconomic status (SES) of the entire sample fell between the low-medium and high-medium category (M ⫽ 2.7; SD ⫽ .89). The SES of the overweight group was significantly lower than the SES of the nonoverweight group (p ⬍ .001). Table 1 presents the ethnicity of the total sample and the subsample of overweight youth. The percentages of African-American and Hispanic/Latino youth in the overweight subsample were significantly higher than the percentage of African-Americans and Hispanic/Latino youth in the total sample (p ⬍ .05). There were also fewer white youth represented in the overweight subsample than in the total sample population. Study Design Details of the sampling design and development of the Connecticut Youth Survey have been published previously [25,26]. Briefly, the sampling design ensured that there was proportional representation of school districts and 7th, 9th, and 11th grade students for each of the Connecticut’s five geographical service delivery areas and levels of socioeconomic strata. A total of 61 schools were included in this study. The final sample was geographically and
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socioeconomically representative of youth in public schools throughout the state, compared with the 1990 census data for Connecticut. The Voice of Connecticut Youth Survey [23] was designed as a comprehensive assessment of the health needs and behaviors of Connecticut’s adolescents. A statewide advisory board determined topics to be covered in the survey. Four existing surveys provided most of the items on the survey: The National Longitudinal Study of Adolescent Health (Add Health Survey), 20,000 7th through 12th graders completed this in-home interview in 1994 [18]; the Family Health Assessment Survey, a Pan American Health Organization–sponsored international survey of familial risk and protective factors [27]; the Minnesota Adolescent Health Survey, a 1986 statewide survey of 7th through 12th graders in Minnesota [28]; and the Centers for Disease Control and Prevention’s Youth Risk Behavior Surveillance, a national survey of 9th through 12th graders administered on an ongoing basis [29]. Experts in the field of adolescent health developed the items on these surveys. The items have demonstrated comparable findings in various study populations, and behaviors have correlated with attitudes, other behaviors, and socioeconomic characteristics in expected directions [18,29 –31]. Items on the Connecticut survey underwent a series of reviews, revisions, and pilot testing. The Connecticut survey included 225 items covering key domains of health risk behaviors and theoretically and empirically derived factors known to enhance or protect against these risk behaviors. The anonymous survey was distributed to students in their classrooms and was completed during one class period. Because the University of Minnesota was contracted to design the Connecticut Youth Survey and analyze the data, study protocols were approved by the University of Minnesota’s Institutional Review Board. Measures Although this survey was not specifically designed to study overweight youth, several items on this survey were relevant to this study. Variables were selected and scales were created to capture the health behavior and psychosocial correlates of overweight adolescents. Scales were also created for the familial factors identified in the adolescent health literature as protecting against adolescent risk behaviors. All of the measures were based on the adolescents’ selfreport. When scales were created, the standard measure of reliability, Cronbach alpha, was calculated to
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measure internal consistency of the items [32]. For these scales, a Cronbach alpha above .5 was considered an acceptable level of correlation among the items. Sociodemographic variables included SES, age, gender, and race. SES was calculated on the basis of adolescents’ self-reports of highest level of parental education and employment status and was divided into four levels with level one, representing the lowest SES and level four representing the highest SES. Questions were asked separately for each parent, and the maximum value of either the mother or the father’s categorical measure was used. Data Analyses Most scaled variables (emotional distress, school performance, family connectedness, and parental monitoring) were calculated by taking the mean value of the constituent items. The scales for highfat/high-sugar snack food consumption and fruit and vegetable consumption are the sum of the constituent items so that values represent the number of servings the respondent reports consuming in one day. For the logistic regressions, all scaled variables were rescaled so that their range was from 0 to 1, thus allowing the resultant odds ratio (OR) estimates to be comparable between the continuous and dichotomous independent variables. We compared the two cohorts (BMI ⬍ 85% and BMI ⱖ 85%) using the Student’s t-test on all healthrelated and psychosocial well-being variables. We then evaluated the potential risk or protective effects of each of the independent variables on each of the nine dependent variables using linear regression for the continuous dependent variables and logistic regression for the dichotomous dependent variables. ORs, using logistic regression, were calculated for extreme dieting and eating breakfast, which were categorical variables. ORs of 1.0 indicate no association. ORs ⬍ 1 indicates that the independent variable is protective against the dependent variable. ORs ⬎ 1.0 indicate that the independent variable enhances the dependent variable. Linear parameter estimates, using linear regression, were calculated for all other variables. A linear parameter estimate of zero indicates that there is no association. A linear parameter estimate less than zero indicates that the independent variable is protective against the dependent variable. A linear parameter estimate greater than zero indicates that the independent variable enhances the dependent variable. For some of the associations, a model using a curvilinear term was a
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Table 2. Self-Reported Health-Related Behaviors and Psychosocial Well-Being Among Overweight and NonOverweight Adolescent Boys and Girls Adolescent Girls (n ⫽ 4651) a
Health-related behaviors Extreme dieters (% extreme) Eat breakfast (% eat breakfast daily) Physical activity (number times/week: 0 – 8) Fruit and vegetable consumption (number servings per day: 0 – 4) High-fat/High-sugar snack food consumption (number serving per day: 0 – 4) Television watching (number hours on school day: 0 –5.5) Psychosocial well-being School performance (0 –10) Emotional distress (0 –10) Future educational plans (0 – 6; 5 ⫽ college)
Adolescent Boys (n ⫽ 4467) b
Non-overweight (n ⫽ 3959)
Overweight (n ⫽ 692)
p Valuec
6.81% 54.0% 3.95 2.14
10.6% 45.0% 3.29 1.93
.002 ⬍.001 ⬍.001 ⬍.001
Non-overweighta Overweightb (n ⫽ 3310) (n ⫽ 1157) p Valuec 2.71% 67.0%
4.19% 58.0%
.025 ⬍.001
2.41
2.16
⬍.001
2.21
2.78
⬍.001
2.40
2.70
⬍.001
3.28 5.16
3.50 4.98
.004 ⬍.001
6.59 2.68 4.96
6.46 2.93 4.82
.014 ⬍.001 .002
a
Nonoverweight refers to youth with BMIs less than the 85th percentile for age and gender. Overweight refers to youth with BMIs ⱖ the 85th percentile for age and gender. c p value based on Student’s t-test. b
better fit than the model using the linear term alone. A linear term alone assumes a straight line association between the independent and dependent variable, whereas a curvilinear term permits a U-shaped or an inverted U-shaped association. The curvilinear term was deemed a better fit when the linear term was not significant but the curvilinear term was significant. The curvilinear term was also considered a better fit when the f statistic of the model significantly increased by the presence of the curvilinear term in the model, compared with the model with the linear term alone. Separate analyses controlling for SES, age, and race were run for adolescent girls and boys. For detection of significant differences, alpha was set at .05.
Results Comparison of Overweight and Non-overweight Adolescents Overweight and non-overweight boys and girls were compared on six health-related behaviors and three psychosocial well-being variables (Table 2). For the health-related behaviors, both overweight girls and boys reported higher rates of extreme dieting, skipping breakfast, and increased television watching than their non-overweight peers. Overweight girls reported exercising fewer times in a week and eating fewer servings of fruits and vegetables per day than the non-overweight girls in the sample. Overweight
boys reported eating more servings of high-fat/highsugar snack foods per day than their non-overweight peers. For the psychosocial well-being variables, both overweight girls and boys reported greater levels of emotional distress and lower expectations of their educational future than the non-overweight youth in the sample. Overweight boys rated their school performance as lower than did non-overweight boys.
Associations of Familial Factors With Health-Related Behaviors and Psychosocial Variables Among Overweight Adolescents Within the overweight group of adolescents, family connectedness, parental expectations, and parental monitoring were assessed independently for their association with the health-related behaviors and psychosocial well-being variables. Among the overweight youth, high levels of family connectedness, high levels of parental expectations, and moderate levels of parental monitoring were positively associated with certain healthy behaviors related to overweight and with higher levels of psychosocial wellbeing. Table 3 presents results from the regression analyses. Family connectedness. Among overweight adolescent girls, higher scores on the family connectedness scale were strongly associated with breakfast-eating,
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Table 3. Associations of Self-Reported Familial Factors With Health-Related Behaviors and Psychosocial Variables Among Overweight Adolescentsa Adolescent Girls (n ⫽ 692) Family Connectedness Est.b Health-related behaviors Extreme dieting 0.19 behaviors Eat breakfast 4.65 Physical activity Fruit and vegetable 0.118 consumption High-fat/high-sugar snack food consumption Television watching Psychosocial well-being School performance 0.283 Emotional distress ⫺0.390 Future educational plans
0.104
p Valuec
Parental Expectations Est.b
p Valuec
Adolescent Boys (n ⫽ 1157)
Parental Monitoring Est.b
p Valuec
Family Connectedness Est.b
p Valuec
p Valuec
Est.b
p Valuec
0.36
⬍.001
5.83
.002
0.134 0.102
⬍.001 ⫺0.222 .003
0.12
.001
2.75 0.162 0.130
.002 ⬍.001 ⬍.001
⫺0.135
⬍.001
0.317 ⫺0.358
⬍.001 ⬍.001
0.271 ⫺0.118
0.201
⬍.001
0.287
⬍.001 ⬍.001
0.258 ⫺0.093
⬍.001 .038
.019
0.200
⬍.001
0.257 ⫺0.272d
.064 .048
Parental Monitoring
Est.b
.008
.008
.006
Parental Expectations
⬍.001 .001 ⫺0.219 0.257d ⬍.001 0.220 ⫺0.307d
.049
.049 .019 .042 .004
a
Analysis controlled for age, race, and socioeconomic status. Parameter estimates for the categorical variables extreme dieting and eating breakfast are odds ratios. Parameter estimates for all other variables are linear. c Nonsignificant results not shown. d Curvilinear term. b
greater school performance, and lower levels of emotional distress. Higher reported levels of family connectedness were moderately associated with higher rates of daily fruit and vegetable consumption and greater expectations of educational future and lower rates of extreme dieting behaviors. The pattern of associations was slightly different for overweight adolescent boys with family connectedness being associated with more health-related behaviors among the boys than the girls. Among overweight boys, higher reported levels of family connectedness were strongly associated with almost all of the health-related behaviors and psychosocial well-being variables. Moderate associations were found between higher levels of family connectedness and less frequent extreme dieting behaviors and more frequent breakfast-eating. Parental expectations. Among overweight adolescent girls, there was a strong association of higher parental expectations with greater school performance and higher expectations of their educational future. Higher parental expectations were moderately associated with lower levels of emotional distress. Similar to family connectedness, parental expectations were associated with more health-related behaviors among the overweight boys than the over-
weight girls. Among the overweight adolescent boys, higher parental expectations were strongly associated with higher rates of weekly exercise, greater school performance, higher expectations of educational future, less frequent extreme dieting behaviors, and lower emotional distress. Among boys, higher parental expectations were moderately associated with higher rates of daily fruit and vegetable consumption. Parental monitoring. There appeared to be a curvilinear (U-shaped) association between level of parental monitoring and extreme dieting behaviors among overweight adolescent girls. Even though not statistically significant, the model using the curvilinear term (p ⫽ .157) yielded a lower p value than the model using the linear term alone (p ⫽ .726). Based on our curvilinear model for overweight adolescent girls, we calculated the probability of extreme dieting along the continuum of parental monitoring. Figure 1 depicts this curvilinear relationship between parental monitoring and extreme dieting behaviors, and illustrates that a moderate amount of parental monitoring was associated with the lowest frequency of extreme dieting behaviors and extreme levels of parental monitoring (high and low) were associated with the highest frequency of extreme dieting behav-
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Figure 1 Relationship Between Reported Level of Parental Monitoring and Probability of Extreme Dieting Behaviors in Girls With Body Mass Index ⬍85%.
iors among overweight adolescent girls. Among overweight girls, there was also a curvilinear (inverted U-shaped) association between level of parental monitoring and the expectations the girls have of their educational future. The model using the curvilinear term (p ⫽ .048) yielded a lower p value than the model using the linear term alone (p ⫽ .064). The nonlinear relationships suggest that a moderate amount of parental monitoring was associated with the greatest level of educational aspirations. In contrast, extreme levels of parental monitoring (in either direction) were associated with lower educational expectations. The pattern of associations was slightly different for overweight adolescent boys with parental monitoring associated with more health-related behaviors and psychosocial variables among the boys than the girls. Among the boys, moderate associations were found between higher levels of parental monitoring and higher rates of extreme dieting and less frequent exercise. The relationship between parental monitoring and eating breakfast appears to be curvilinear. Although it was not significant, the model using the curvilinear term (p ⫽ .217) yielded a better p value than the model using the linear term alone (p ⫽ .477), suggesting that a moderate amount of parental monitoring was associated with the highest rates of eating breakfast. There was a curvilinear association between parental monitoring and emotional distress and expectations of their educational future, indicat-
ing that extremes (in either direction) of monitoring were associated with more emotional distress and lower educational aspirations in overweight adolescent boys. Moderate amounts of parental monitoring were associated with the highest levels of emotional well-being and educational aspirations.
Discussion Researchers have hypothesized that the negative stereotyping and stigmatization that overweight youth face makes them more vulnerable to engage in certain unhealthy behaviors and to experience psychosocial difficulties than their non-overweight peers [4,33]. This study found overweight adolescent boys and girls engaged in higher levels of unhealthy behaviors and reported lower frequencies of psychosocial well-being than their non-overweight peers. The higher levels of unhealthy behaviors such as extreme dieting, skipping meals, and television watching in the study sample is consistent with previous research studying the dieting, eating, and activity patterns of overweight youth [7–10]. In the psychosocial domain, the overweight youth in this sample rated their school performance and educational future lower than their non-overweight peers. One explanation may be that overweight adolescents have somehow learned to expect less of their current and future educational attainment. This finding
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should not be surprising in light of previous research indicating that overweight during adolescence, particularly among girls, is associated with fewer years of school completed and higher rates of poverty and unemployment than those who were not overweight during adolescence [4]. Additionally, the higher levels of emotional distress among overweight youth provide further evidence that overweight adolescents are a vulnerable group. Given that overweight adolescents are a vulnerable population, this study examined familial variables that are hypothesized to serve as protective factors by decreasing the frequency of unhealthy behaviors and emotional distress and increasing the presence of healthy behaviors and psychosocial wellbeing. Results of this study are consistent with research identifying familial connectedness and parental expectations as important protective forces against numerous risk behaviors during adolescence [16,18 –22]. Among overweight girls as well as boys, the most powerful protective factor across healthrelated behaviors and psychosocial variables was family connectedness. Overweight teenagers who reported they can talk to their parents about their problems, their parents understand and care about them, and they talk or share activities with their parents were more likely to be involved in healthy behaviors, score higher on the psychosocial wellbeing scales, and to be involved in fewer healthcompromising behaviors. Higher parental expectations was also associated with healthy behaviors among boys but appeared unrelated to the health behaviors of girls. Higher parental expectations, however, appear to act as a protective factor for psychosocial difficulties among both overweight boys and girls. Higher levels of parental monitoring was associated with only a few health-related behaviors among boys. Moderate amounts of parental monitoring, however, were associated with the highest rates of breakfast consumption and educational aspirations and the lowest rates of emotional distress among boys. Moderate amounts of parental monitoring were associated with the lowest rates of extreme dieting behaviors and the highest educational aspirations among girls. Extremes in parental monitoring (high and low) were associated with lower educational aspirations among boys and girls, lower breakfast consumption among boys, higher emotional distress among boys, and higher rates of extreme dieting behaviors among girls. It is important to recognize that parents’ level of monitoring of their teenager does not develop in a vacuum; rather, it is
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likely to be a function of numerous variables including their teenagers’ past and present behavior. In light of the reciprocal manner in which levels parental monitoring develop, this finding is congruent with what is known developmentally about adolescents; having the opportunity to make some decisions without parental involvement serves the adolescents’ developmental need for autonomy and independence and is likely to lead to better psychosocial adjustment during adolescence. When considering the findings of this study, both strengths and limitations should be taken into account. Strengths of the study were the large, diverse, and statewide representative sample of adolescents in the study population; the comprehensive survey instrument; and the study being one of the first to examine these associations in overweight youth. Using data derived from a comprehensive, anonymous, self-report survey, however, has its constraints. First, one relinquishes the ability to gather in-depth and specific information on all variables and must, at times, use a few questions to represent complex domains. Findings, therefore, can provide direction for potential areas for more in-depth future studies. Second, using an anonymous survey precludes the verification of responses and external validation of important variables such as BMI and fruit, vegetable, and snack food consumption. With regard to BMI, adolescents who are overweight tend to underreport their weight [34 –36]. This may explain why when using the self-reported data on height and weight to calculate BMI, the prevalence of overweight in girls was lower than the most recent national estimate [1]. The large difference in the number of girls reporting heights and weights in the overweight range, compared with boys (15% vs. 26%, respectively), may be because girls are more sensitive to weight-related issues than boys, and, therefore, overweight girls may have been more likely than overweight boys to underestimate their weight or leave this item blank. The impact of fewer girls in the overweight sample may have resulted in lower power for the analyses and highlights the need for examining the research questions with actual BMI data. With regard to fruit, vegetable, and snack food consumption, although the limitations of previous day diet recall methods are acknowledged, the questions used in the Connecticut Youth Survey are widely accepted, commonly used, and have been previously used in a large national youth survey [29]. In addition, when drawing conclusions from this study, it is also important to remember that this is a cross-sectional design, which does not provide infor-
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mation about the direction of causality of associations. It may be that among overweight youth engaging in health-compromising behaviors, parental expectations (or perceived expectations) have been lowered or parental monitoring has increased. Therefore, we cannot conclude that familial factors are influencing behavioral patterns, although it seems likely in light of consistent previous research findings. Finally, although there was a higher representation of ethnic minority and lower SES adolescents in the overweight group, the differences found in overweight status among ethnic groups and SES are consistent with previous studies documenting higher rates of overweight in African-American and other ethnic minorities than in white Americans and an inverse association between overweight and SES [1,37,38]. These findings highlight family factors related to healthy psychosocial development and health maintenance among overweight adolescents. Results of this study suggest that improving the relationship between adolescents who are overweight and their parents may have a positive impact on the healthrelated behaviors and psychosocial well-being of the adolescent. The positive family relationship may serve as a protective factor against the negative stereotyping and discrimination that overweight teenagers are likely to face. Satisfying and developmentally appropriate parent-adolescent relationships appear to be associated with reduced behavioral and psychosocial risk factors associated with overweight during adolescence. This study was supported in part by the University of Minnesota Adolescent Health Training Program, Grant #5-T71-MC-00006-22, Maternal and Child Health Bureau, Health Resources and Services Administration, U.S. Department of Health and Human Resources.
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image perceptions in adolescents. Int J Eat Disord 1995;18: 173–9. Cronbach LJ. Coefficient alpha and the internal structure of tests. Psychometrika 1951;48:99 –111. Ross C. Overweight and depression. J Health Soc Behav 1994;35:63–78. Fortenberry JD. Reliability of adolescents’ reports of height and weight. J Adolesc Health 1992;13:114 –7. Hauck FR, White L, Guichan C, et al. Inaccuracy of selfreported weights and heights among American Indian adolescents. Ann Epidemiol 1995;5:386 –92. Himes JH, Story M. Validity of self-reported weight and stature of American Indian youth. J Adolesc Health 1992;13: 118 –20. Wolf AM, Gortmaker SL, Cheung L, et al. Activity, inactivity, and obesity: Racial, ethnic, and age differences among schoolgirls. Am J Public Health 1993;83:1625–7. National Heart, Lung, and Blood Institute Growth and Health Study Research Group. Obesity and cardiovascular disease risk factors in black and white girls: The NHLBI growth and health study. Am J Public Health 1992;82:1613–20.
ORIGINAL ARTICLE
Unhealthy Behaviors and Psychosocial Difficulties Among Overweight Adolescents: The Potential Impact of Familial Factors ALISON E. MELLIN, Ph.D., DIANNE NEUMARK-SZTAINER, Ph.D., M.P.H., R.D., MARY STORY, Ph.D. R.D., MARJORIE IRELAND, Ph.D., AND MICHAEL D. RESNICK, Ph.D.
Purpose: To compare overweight and non-overweight youth on a selection of self-reported eating, physical activity, dieting, educational, and emotional variables and identify familial factors that serve as protective forces against unhealthy behaviors and psychosocial difficulties among overweight adolescents. Methods: Data were taken from a 1996 cross-sectional school-based survey of 9957 adolescents in grades 7, 9, and 11. Based on self-reported heights and weights, respondents were categorized as “overweight” (body mass index) >85th percentile or “non-overweight.” Student’s t-tests were used to compare the non-overweight and overweight sample on the self-reported health-related behaviors and psychosocial variables. Logistic and linear regressions were used to identify familial factors associated with a reduced risk of engaging in unhealthy behaviors and experiencing psychosocial distress. Results: Overweight adolescents reported engaging in significantly more unhealthy behaviors and experiencing more psychosocial distress than their non-overweight peers. Among the overweight youth, higher levels of reported family connectedness and parental expectations and moderate levels of parental monitoring were associated with the lowest levels of unhealthy behaviors and psychosocial distress. Conclusions: Satisfying and developmentally appropriate parent-adolescent relationships are associated From the Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis, Minnesota (A.E.M., D.N.-S., M.S.); and Division of General Pediatrics and Adolescent Health, University of Minnesota, Minneapolis, Minnesota (M.I., M.D.R.). Address correspondence to: Alison Mellin, Ph.D., Division of Epidemiology, University of Minnesota School of Public Health, Suite 300, 1300 South Second Street, Minneapolis, Minnesota 55454-1015. E-mail: [email protected]. Manuscript accepted October 15, 2001.
with reduced behavioral and psychosocial risk factors associated with overweight during adolescence. © Society for Adolescent Medicine, 2002
KEY WORDS:
Adolescence Family Obesity Overweight Protective factors
Being an overweight adolescent in the United States is becoming increasingly common. Data from the most recent National Health and Nutrition Examination Survey (NHANES III, 1988 –1991) indicate that approximately 22% of adolescents are overweight [1]. Despite the increasing numbers of overweight youth, this group continues to experience stigmatization and discrimination as well as pressure to be thin from the media, their peers, and even health care professionals [2– 6]. Researchers hypothesize that weight discrimination, presence of negative stereotypes, and pressure to conform to an unattainable ideal body shape may be some of the reasons overweight youth are at risk for certain unhealthy behaviors and adverse psychological, social, and economic outcomes. Behavioral correlates of overweight in teenagers include more time in sedentary activities (e.g. television watching), less time in physical activities, and higher consumption of high fat/high sugar foods [7–9]. Overweight adolescent girls are also more
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likely to engage in unhealthy dieting behaviors including skipping meals and binge eating [10]. Overweight during adolescence has also been linked, albeit inconsistently, with lower self-esteem, lower self-concept, and higher rates of psychosocial difficulties [11–14]. In the face of social pressure to be thin, however, there are many overweight adolescents who do not experience psychosocial problems [5,10,11,15]. What could explain the variability in psychosocial functioning among overweight youth? To answer this question, research has examined the impact of familial factors on overweight youth. Bruch [16] studied obese individuals from childhood through adulthood and found a wide variation among individuals in self-concept and psychosocial well-being. Bruch accounted for a large portion of the variation in psychological functioning to the obese child’s family; children in supportive and accepting families fared better in both psychological adjustment and weight management than children who were in a family in which they were admonished for their weight and whose familial relationships were characterized as dysfunctional. Epstein et al. [17] also examined familial correlates of psychological problems in obese children and found that among moderately obese children seeking treatment, parental psychopathology had the strongest relationship with child psychosocial problems, even stronger than the child’s body mass index (BMI). Research on risk and protective factors indicates that family context variables have a strong association with the emotional well-being of adolescents and their health-related behaviors [18 –22]. To date, there is little research examining the impact of family connectedness, parental expectations, and parental monitoring on the health-related behaviors and psychosocial well-being of overweight adolescents. The purpose of this study was to: (a) compare overweight and non-overweight adolescents on selected nutrition, physical activity, and dieting behaviors and psychosocial well-being variables, and (b) examine the association of selected family factors with health-related behaviors and psychosocial variables among overweight adolescents.
Methods Study Population The study population included a representative sampling of 7th, 9th, and 11th grade public school students (N ⫽ 9957) from Connecticut who partici-
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Table 1. Ethnicity of Total Sample Population and Subsample of Overweight Youth
Ethnicity
Total Study Population (%) (n ⫽ 9024)
Overweight Subsample (%) (n ⫽ 1829)
White African-American Hispanic/Latino Asian/Pacific Islander American Indian Multiracial
74.0 8.9 6.9 2.5 0.7 7.0
64.0 13.7 10.1 1.8 0.9 9.1
pated in a statewide survey of adolescent health from 1995 to 1996 [23]. BMI (weight in kilograms/ height in meters squared) was calculated from selfreported weight and height measurements. The 839 youth who did not self-report their height or weight or who had a spuriously high (⬎50) or extremely low BMI (⬍10) were excluded from the study, resulting in a sample of 9118 for analysis. Adolescents with a BMI equal to or above the 85th percentile were classified as overweight [24]. Of females, 15% (n ⫽ 692), and of males, 26% (n ⫽ 1157) were categorized as overweight. The mean age of the entire sample was 14.4 (SD ⫽ 2.88) years with no significant differences in age between the nonoverweight and overweight groups. The mean socioeconomic status (SES) of the entire sample fell between the low-medium and high-medium category (M ⫽ 2.7; SD ⫽ .89). The SES of the overweight group was significantly lower than the SES of the nonoverweight group (p ⬍ .001). Table 1 presents the ethnicity of the total sample and the subsample of overweight youth. The percentages of African-American and Hispanic/Latino youth in the overweight subsample were significantly higher than the percentage of African-Americans and Hispanic/Latino youth in the total sample (p ⬍ .05). There were also fewer white youth represented in the overweight subsample than in the total sample population. Study Design Details of the sampling design and development of the Connecticut Youth Survey have been published previously [25,26]. Briefly, the sampling design ensured that there was proportional representation of school districts and 7th, 9th, and 11th grade students for each of the Connecticut’s five geographical service delivery areas and levels of socioeconomic strata. A total of 61 schools were included in this study. The final sample was geographically and
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socioeconomically representative of youth in public schools throughout the state, compared with the 1990 census data for Connecticut. The Voice of Connecticut Youth Survey [23] was designed as a comprehensive assessment of the health needs and behaviors of Connecticut’s adolescents. A statewide advisory board determined topics to be covered in the survey. Four existing surveys provided most of the items on the survey: The National Longitudinal Study of Adolescent Health (Add Health Survey), 20,000 7th through 12th graders completed this in-home interview in 1994 [18]; the Family Health Assessment Survey, a Pan American Health Organization–sponsored international survey of familial risk and protective factors [27]; the Minnesota Adolescent Health Survey, a 1986 statewide survey of 7th through 12th graders in Minnesota [28]; and the Centers for Disease Control and Prevention’s Youth Risk Behavior Surveillance, a national survey of 9th through 12th graders administered on an ongoing basis [29]. Experts in the field of adolescent health developed the items on these surveys. The items have demonstrated comparable findings in various study populations, and behaviors have correlated with attitudes, other behaviors, and socioeconomic characteristics in expected directions [18,29 –31]. Items on the Connecticut survey underwent a series of reviews, revisions, and pilot testing. The Connecticut survey included 225 items covering key domains of health risk behaviors and theoretically and empirically derived factors known to enhance or protect against these risk behaviors. The anonymous survey was distributed to students in their classrooms and was completed during one class period. Because the University of Minnesota was contracted to design the Connecticut Youth Survey and analyze the data, study protocols were approved by the University of Minnesota’s Institutional Review Board. Measures Although this survey was not specifically designed to study overweight youth, several items on this survey were relevant to this study. Variables were selected and scales were created to capture the health behavior and psychosocial correlates of overweight adolescents. Scales were also created for the familial factors identified in the adolescent health literature as protecting against adolescent risk behaviors. All of the measures were based on the adolescents’ selfreport. When scales were created, the standard measure of reliability, Cronbach alpha, was calculated to
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measure internal consistency of the items [32]. For these scales, a Cronbach alpha above .5 was considered an acceptable level of correlation among the items. Sociodemographic variables included SES, age, gender, and race. SES was calculated on the basis of adolescents’ self-reports of highest level of parental education and employment status and was divided into four levels with level one, representing the lowest SES and level four representing the highest SES. Questions were asked separately for each parent, and the maximum value of either the mother or the father’s categorical measure was used. Data Analyses Most scaled variables (emotional distress, school performance, family connectedness, and parental monitoring) were calculated by taking the mean value of the constituent items. The scales for highfat/high-sugar snack food consumption and fruit and vegetable consumption are the sum of the constituent items so that values represent the number of servings the respondent reports consuming in one day. For the logistic regressions, all scaled variables were rescaled so that their range was from 0 to 1, thus allowing the resultant odds ratio (OR) estimates to be comparable between the continuous and dichotomous independent variables. We compared the two cohorts (BMI ⬍ 85% and BMI ⱖ 85%) using the Student’s t-test on all healthrelated and psychosocial well-being variables. We then evaluated the potential risk or protective effects of each of the independent variables on each of the nine dependent variables using linear regression for the continuous dependent variables and logistic regression for the dichotomous dependent variables. ORs, using logistic regression, were calculated for extreme dieting and eating breakfast, which were categorical variables. ORs of 1.0 indicate no association. ORs ⬍ 1 indicates that the independent variable is protective against the dependent variable. ORs ⬎ 1.0 indicate that the independent variable enhances the dependent variable. Linear parameter estimates, using linear regression, were calculated for all other variables. A linear parameter estimate of zero indicates that there is no association. A linear parameter estimate less than zero indicates that the independent variable is protective against the dependent variable. A linear parameter estimate greater than zero indicates that the independent variable enhances the dependent variable. For some of the associations, a model using a curvilinear term was a
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Table 2. Self-Reported Health-Related Behaviors and Psychosocial Well-Being Among Overweight and NonOverweight Adolescent Boys and Girls Adolescent Girls (n ⫽ 4651) a
Health-related behaviors Extreme dieters (% extreme) Eat breakfast (% eat breakfast daily) Physical activity (number times/week: 0 – 8) Fruit and vegetable consumption (number servings per day: 0 – 4) High-fat/High-sugar snack food consumption (number serving per day: 0 – 4) Television watching (number hours on school day: 0 –5.5) Psychosocial well-being School performance (0 –10) Emotional distress (0 –10) Future educational plans (0 – 6; 5 ⫽ college)
Adolescent Boys (n ⫽ 4467) b
Non-overweight (n ⫽ 3959)
Overweight (n ⫽ 692)
p Valuec
6.81% 54.0% 3.95 2.14
10.6% 45.0% 3.29 1.93
.002 ⬍.001 ⬍.001 ⬍.001
Non-overweighta Overweightb (n ⫽ 3310) (n ⫽ 1157) p Valuec 2.71% 67.0%
4.19% 58.0%
.025 ⬍.001
2.41
2.16
⬍.001
2.21
2.78
⬍.001
2.40
2.70
⬍.001
3.28 5.16
3.50 4.98
.004 ⬍.001
6.59 2.68 4.96
6.46 2.93 4.82
.014 ⬍.001 .002
a
Nonoverweight refers to youth with BMIs less than the 85th percentile for age and gender. Overweight refers to youth with BMIs ⱖ the 85th percentile for age and gender. c p value based on Student’s t-test. b
better fit than the model using the linear term alone. A linear term alone assumes a straight line association between the independent and dependent variable, whereas a curvilinear term permits a U-shaped or an inverted U-shaped association. The curvilinear term was deemed a better fit when the linear term was not significant but the curvilinear term was significant. The curvilinear term was also considered a better fit when the f statistic of the model significantly increased by the presence of the curvilinear term in the model, compared with the model with the linear term alone. Separate analyses controlling for SES, age, and race were run for adolescent girls and boys. For detection of significant differences, alpha was set at .05.
Results Comparison of Overweight and Non-overweight Adolescents Overweight and non-overweight boys and girls were compared on six health-related behaviors and three psychosocial well-being variables (Table 2). For the health-related behaviors, both overweight girls and boys reported higher rates of extreme dieting, skipping breakfast, and increased television watching than their non-overweight peers. Overweight girls reported exercising fewer times in a week and eating fewer servings of fruits and vegetables per day than the non-overweight girls in the sample. Overweight
boys reported eating more servings of high-fat/highsugar snack foods per day than their non-overweight peers. For the psychosocial well-being variables, both overweight girls and boys reported greater levels of emotional distress and lower expectations of their educational future than the non-overweight youth in the sample. Overweight boys rated their school performance as lower than did non-overweight boys.
Associations of Familial Factors With Health-Related Behaviors and Psychosocial Variables Among Overweight Adolescents Within the overweight group of adolescents, family connectedness, parental expectations, and parental monitoring were assessed independently for their association with the health-related behaviors and psychosocial well-being variables. Among the overweight youth, high levels of family connectedness, high levels of parental expectations, and moderate levels of parental monitoring were positively associated with certain healthy behaviors related to overweight and with higher levels of psychosocial wellbeing. Table 3 presents results from the regression analyses. Family connectedness. Among overweight adolescent girls, higher scores on the family connectedness scale were strongly associated with breakfast-eating,
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Table 3. Associations of Self-Reported Familial Factors With Health-Related Behaviors and Psychosocial Variables Among Overweight Adolescentsa Adolescent Girls (n ⫽ 692) Family Connectedness Est.b Health-related behaviors Extreme dieting 0.19 behaviors Eat breakfast 4.65 Physical activity Fruit and vegetable 0.118 consumption High-fat/high-sugar snack food consumption Television watching Psychosocial well-being School performance 0.283 Emotional distress ⫺0.390 Future educational plans
0.104
p Valuec
Parental Expectations Est.b
p Valuec
Adolescent Boys (n ⫽ 1157)
Parental Monitoring Est.b
p Valuec
Family Connectedness Est.b
p Valuec
p Valuec
Est.b
p Valuec
0.36
⬍.001
5.83
.002
0.134 0.102
⬍.001 ⫺0.222 .003
0.12
.001
2.75 0.162 0.130
.002 ⬍.001 ⬍.001
⫺0.135
⬍.001
0.317 ⫺0.358
⬍.001 ⬍.001
0.271 ⫺0.118
0.201
⬍.001
0.287
⬍.001 ⬍.001
0.258 ⫺0.093
⬍.001 .038
.019
0.200
⬍.001
0.257 ⫺0.272d
.064 .048
Parental Monitoring
Est.b
.008
.008
.006
Parental Expectations
⬍.001 .001 ⫺0.219 0.257d ⬍.001 0.220 ⫺0.307d
.049
.049 .019 .042 .004
a
Analysis controlled for age, race, and socioeconomic status. Parameter estimates for the categorical variables extreme dieting and eating breakfast are odds ratios. Parameter estimates for all other variables are linear. c Nonsignificant results not shown. d Curvilinear term. b
greater school performance, and lower levels of emotional distress. Higher reported levels of family connectedness were moderately associated with higher rates of daily fruit and vegetable consumption and greater expectations of educational future and lower rates of extreme dieting behaviors. The pattern of associations was slightly different for overweight adolescent boys with family connectedness being associated with more health-related behaviors among the boys than the girls. Among overweight boys, higher reported levels of family connectedness were strongly associated with almost all of the health-related behaviors and psychosocial well-being variables. Moderate associations were found between higher levels of family connectedness and less frequent extreme dieting behaviors and more frequent breakfast-eating. Parental expectations. Among overweight adolescent girls, there was a strong association of higher parental expectations with greater school performance and higher expectations of their educational future. Higher parental expectations were moderately associated with lower levels of emotional distress. Similar to family connectedness, parental expectations were associated with more health-related behaviors among the overweight boys than the over-
weight girls. Among the overweight adolescent boys, higher parental expectations were strongly associated with higher rates of weekly exercise, greater school performance, higher expectations of educational future, less frequent extreme dieting behaviors, and lower emotional distress. Among boys, higher parental expectations were moderately associated with higher rates of daily fruit and vegetable consumption. Parental monitoring. There appeared to be a curvilinear (U-shaped) association between level of parental monitoring and extreme dieting behaviors among overweight adolescent girls. Even though not statistically significant, the model using the curvilinear term (p ⫽ .157) yielded a lower p value than the model using the linear term alone (p ⫽ .726). Based on our curvilinear model for overweight adolescent girls, we calculated the probability of extreme dieting along the continuum of parental monitoring. Figure 1 depicts this curvilinear relationship between parental monitoring and extreme dieting behaviors, and illustrates that a moderate amount of parental monitoring was associated with the lowest frequency of extreme dieting behaviors and extreme levels of parental monitoring (high and low) were associated with the highest frequency of extreme dieting behav-
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Figure 1 Relationship Between Reported Level of Parental Monitoring and Probability of Extreme Dieting Behaviors in Girls With Body Mass Index ⬍85%.
iors among overweight adolescent girls. Among overweight girls, there was also a curvilinear (inverted U-shaped) association between level of parental monitoring and the expectations the girls have of their educational future. The model using the curvilinear term (p ⫽ .048) yielded a lower p value than the model using the linear term alone (p ⫽ .064). The nonlinear relationships suggest that a moderate amount of parental monitoring was associated with the greatest level of educational aspirations. In contrast, extreme levels of parental monitoring (in either direction) were associated with lower educational expectations. The pattern of associations was slightly different for overweight adolescent boys with parental monitoring associated with more health-related behaviors and psychosocial variables among the boys than the girls. Among the boys, moderate associations were found between higher levels of parental monitoring and higher rates of extreme dieting and less frequent exercise. The relationship between parental monitoring and eating breakfast appears to be curvilinear. Although it was not significant, the model using the curvilinear term (p ⫽ .217) yielded a better p value than the model using the linear term alone (p ⫽ .477), suggesting that a moderate amount of parental monitoring was associated with the highest rates of eating breakfast. There was a curvilinear association between parental monitoring and emotional distress and expectations of their educational future, indicat-
ing that extremes (in either direction) of monitoring were associated with more emotional distress and lower educational aspirations in overweight adolescent boys. Moderate amounts of parental monitoring were associated with the highest levels of emotional well-being and educational aspirations.
Discussion Researchers have hypothesized that the negative stereotyping and stigmatization that overweight youth face makes them more vulnerable to engage in certain unhealthy behaviors and to experience psychosocial difficulties than their non-overweight peers [4,33]. This study found overweight adolescent boys and girls engaged in higher levels of unhealthy behaviors and reported lower frequencies of psychosocial well-being than their non-overweight peers. The higher levels of unhealthy behaviors such as extreme dieting, skipping meals, and television watching in the study sample is consistent with previous research studying the dieting, eating, and activity patterns of overweight youth [7–10]. In the psychosocial domain, the overweight youth in this sample rated their school performance and educational future lower than their non-overweight peers. One explanation may be that overweight adolescents have somehow learned to expect less of their current and future educational attainment. This finding
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should not be surprising in light of previous research indicating that overweight during adolescence, particularly among girls, is associated with fewer years of school completed and higher rates of poverty and unemployment than those who were not overweight during adolescence [4]. Additionally, the higher levels of emotional distress among overweight youth provide further evidence that overweight adolescents are a vulnerable group. Given that overweight adolescents are a vulnerable population, this study examined familial variables that are hypothesized to serve as protective factors by decreasing the frequency of unhealthy behaviors and emotional distress and increasing the presence of healthy behaviors and psychosocial wellbeing. Results of this study are consistent with research identifying familial connectedness and parental expectations as important protective forces against numerous risk behaviors during adolescence [16,18 –22]. Among overweight girls as well as boys, the most powerful protective factor across healthrelated behaviors and psychosocial variables was family connectedness. Overweight teenagers who reported they can talk to their parents about their problems, their parents understand and care about them, and they talk or share activities with their parents were more likely to be involved in healthy behaviors, score higher on the psychosocial wellbeing scales, and to be involved in fewer healthcompromising behaviors. Higher parental expectations was also associated with healthy behaviors among boys but appeared unrelated to the health behaviors of girls. Higher parental expectations, however, appear to act as a protective factor for psychosocial difficulties among both overweight boys and girls. Higher levels of parental monitoring was associated with only a few health-related behaviors among boys. Moderate amounts of parental monitoring, however, were associated with the highest rates of breakfast consumption and educational aspirations and the lowest rates of emotional distress among boys. Moderate amounts of parental monitoring were associated with the lowest rates of extreme dieting behaviors and the highest educational aspirations among girls. Extremes in parental monitoring (high and low) were associated with lower educational aspirations among boys and girls, lower breakfast consumption among boys, higher emotional distress among boys, and higher rates of extreme dieting behaviors among girls. It is important to recognize that parents’ level of monitoring of their teenager does not develop in a vacuum; rather, it is
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likely to be a function of numerous variables including their teenagers’ past and present behavior. In light of the reciprocal manner in which levels parental monitoring develop, this finding is congruent with what is known developmentally about adolescents; having the opportunity to make some decisions without parental involvement serves the adolescents’ developmental need for autonomy and independence and is likely to lead to better psychosocial adjustment during adolescence. When considering the findings of this study, both strengths and limitations should be taken into account. Strengths of the study were the large, diverse, and statewide representative sample of adolescents in the study population; the comprehensive survey instrument; and the study being one of the first to examine these associations in overweight youth. Using data derived from a comprehensive, anonymous, self-report survey, however, has its constraints. First, one relinquishes the ability to gather in-depth and specific information on all variables and must, at times, use a few questions to represent complex domains. Findings, therefore, can provide direction for potential areas for more in-depth future studies. Second, using an anonymous survey precludes the verification of responses and external validation of important variables such as BMI and fruit, vegetable, and snack food consumption. With regard to BMI, adolescents who are overweight tend to underreport their weight [34 –36]. This may explain why when using the self-reported data on height and weight to calculate BMI, the prevalence of overweight in girls was lower than the most recent national estimate [1]. The large difference in the number of girls reporting heights and weights in the overweight range, compared with boys (15% vs. 26%, respectively), may be because girls are more sensitive to weight-related issues than boys, and, therefore, overweight girls may have been more likely than overweight boys to underestimate their weight or leave this item blank. The impact of fewer girls in the overweight sample may have resulted in lower power for the analyses and highlights the need for examining the research questions with actual BMI data. With regard to fruit, vegetable, and snack food consumption, although the limitations of previous day diet recall methods are acknowledged, the questions used in the Connecticut Youth Survey are widely accepted, commonly used, and have been previously used in a large national youth survey [29]. In addition, when drawing conclusions from this study, it is also important to remember that this is a cross-sectional design, which does not provide infor-
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mation about the direction of causality of associations. It may be that among overweight youth engaging in health-compromising behaviors, parental expectations (or perceived expectations) have been lowered or parental monitoring has increased. Therefore, we cannot conclude that familial factors are influencing behavioral patterns, although it seems likely in light of consistent previous research findings. Finally, although there was a higher representation of ethnic minority and lower SES adolescents in the overweight group, the differences found in overweight status among ethnic groups and SES are consistent with previous studies documenting higher rates of overweight in African-American and other ethnic minorities than in white Americans and an inverse association between overweight and SES [1,37,38]. These findings highlight family factors related to healthy psychosocial development and health maintenance among overweight adolescents. Results of this study suggest that improving the relationship between adolescents who are overweight and their parents may have a positive impact on the healthrelated behaviors and psychosocial well-being of the adolescent. The positive family relationship may serve as a protective factor against the negative stereotyping and discrimination that overweight teenagers are likely to face. Satisfying and developmentally appropriate parent-adolescent relationships appear to be associated with reduced behavioral and psychosocial risk factors associated with overweight during adolescence. This study was supported in part by the University of Minnesota Adolescent Health Training Program, Grant #5-T71-MC-00006-22, Maternal and Child Health Bureau, Health Resources and Services Administration, U.S. Department of Health and Human Resources.
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