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This article was downloaded by: [Universitat Politècnica de València]On: 25 October 2014, At: 23:34Publisher: RoutledgeInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,37-41 Mortimer Street, London W1T 3JH, UK
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Parental Locus of Control: Associations to Adherenceand Outcomes in the Treatment of PediatricOverweightEve A. Rosno a , Ric G. Steele a , Craig A. Johnston a & Brandon S. Aylward aa Clinical Child Psychology Program , University of Kansas , Lawrence, KSPublished online: 25 Apr 2008.
To cite this article: Eve A. Rosno , Ric G. Steele , Craig A. Johnston & Brandon S. Aylward (2008) Parental Locus of Control:Associations to Adherence and Outcomes in the Treatment of Pediatric Overweight, Children's Health Care, 37:2, 126-144,DOI: 10.1080/02739610802006544
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Children’s Health Care, 37:126–144, 2008
Copyright © Taylor & Francis Group, LLC
ISSN: 0273-9615 print/1532-6888 online
DOI: 10.1080/02739610802006544
Parental Locus of Control: Associationsto Adherence and Outcomes in theTreatment of Pediatric Overweight
Eve A. Rosno, Ric G. Steele, Craig A. Johnston, andBrandon S. Aylward
Clinical Child Psychology Program
University of Kansas, Lawrence, KS
This study examined the association of parents’ locus of control (LOC) to child
adherence and outcomes in a behaviorally based family treatment for pediatric
overweight. A condition-specific multidimensional health LOC measure was ad-
ministered to parents of 63 overweight children enrolled in a 10-week obesity
treatment program. Hierarchical multiple regression analyses indicated that parents
who reported a strong belief in the influence of powerful others had children who
were more successful throughout treatment .p < :01/. In contrast, those parents
who reported that their child’s outcome was due to chance had children with worse
treatment outcomes .p < :05/. Regarding adherence, parents with strong beliefs
in chance and those who felt they were more responsible for the child’s weight
problem (i.e., higher parent-internal LOC) attended fewer sessions. The findings
of this study lend preliminary support to the role of parental LOC in relation to the
treatment of pediatric overweight. Research and clinical implications are discussed
in light of the findings of this study.
As the prevalence of pediatric overweight continues to increase, and the age of
onset for pediatric weight problems continues to decrease, weight management
and obesity prevention programs for children and youth will continue to capture
the attention of researchers, clinicians, and policymakers for the foreseeable
future. Simply put, a greater proportion of children are becoming overweight,
Correspondence should be addressed to Ric G. Steele, Clinical Child Psychology Program,
2011 Dole Human Development Center, University of Kansas, 1000 Sunnyside Ave., Lawrence, KS
66045-7555. E-mail: [email protected]
126
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LOCUS OF CONTROL AND OVERWEIGHT 127
children are becoming overweight at earlier ages, and the health consequences
resulting from child weight problems are affecting greater percentages of chil-
dren than ever before (Jolliffe, 2004; Ogden et el., 2006; Schwimmer, Burwinkle,
& Varni, 2003; Stein & Colditz, 2004).
Fortunately, a number of programs have been developed to treat children who
are overweight, many of them demonstrating clinical efficacy and effectiveness
(see Jelalian & Saelens, 1999). These programs generally include behavioral
techniques such as stimulus control, self-monitoring, reinforcement of behavior
change, and modeling of healthier behavior, in conjunction with nutrition edu-
cation and promotion of increased physical activity (e.g., Epstein, 1996; Israel,
Stolmaker, Sharp, Silverman, & Simon, 1984). However, beyond the inclusion
of these treatment components, research consistently indicates that parental
involvement is one crucial element in the treatment of child weight problems
(e.g., Brann & Skinner, 2005; Epstein, Wing, & Valoski, 1985; Kirschenbaum,
Germann, & Rich, 2005). Such studies indicate that programs involving both
children and their parents in attempts to manage childhood weight problems fare
better than programs designed for children alone.
The association of parental involvement to child weight management success
is intuitively appealing. Parents are responsible for much of their children’s
environments (e.g., food availability; reinforcement), adherence to some pro-
gram components (e.g., attendance), and modeling of healthier lifestyles (e.g.,
increased physical activity). However, the degree to which parents actually
promote adherence to behaviorally based weight management programs for
children remains largely unknown. Thus, a greater understanding of parents’
decision-making processes vis-à-vis child weight management programs remains
necessary to maximize youth outcomes in prevention and treatment programs
(Zeller & Daniels, 2004).
Among the factors that may explain some portion of the variance in child
health outcomes are parents’ beliefs about the causes of, potential solutions
to, and confidence in managing their children’s weight problems. Perceived
behavioral control, which has been defined as the perceived ease or difficulty
of performing a behavior, has been proposed as an overarching construct com-
prising two subordinate components: self-efficacy and locus of control (LOC;
see Ajzen, 2002). Self-efficacy (Bandura, 1977) is an individual’s confidence in
his or her ability to effectively cope in a given situation. Although some studies
have found significant associations between self-efficacy and both weight loss
and later weight loss maintenance (e.g., Dennis & Goldberg, 1996; Rodin, Elias,
Silberstein, & Wagner, 1988; Teixeira et al., 2004), some recent studies do not
entirely confirm these findings (e.g., Cargill, Clark, Pera, Niaura, & Abrams,
1999; Fontaine & Cheskin, 1997).
Also included within the umbrella of perceived behavioral control, the concept
of LOC (Rotter, 1954) has received substantial support as a predictor of numer-
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128 ROSNO, STEELE, JOHNSTON, AYLWARD
ous health outcomes (e.g., Kelly et al., 1990; Quadrel & Lau, 1989; Spikmans
et al., 2003). Generally, these studies suggest that individuals evidencing an
internal health LOC (i.e., the perception that health outcomes are the result of
individuals’ behaviors) have greater success in a variety of health promoting
programs than adults evidencing an external LOC. Similar findings have been
reported in the adult weight management literature as well (e.g., Allison &
Engel, 1995; Holt, Clark, & Kreuter, 2001; Nir & Neumann, 1995; Silverman,
Israel, & Shapiro, 1986), despite some findings to the contrary (e.g., Tobias
& MacDonald, 1977; Williams, Grow, Freedman, Ryan, & Deci, 1996). In
examining the relation between self-efficacy and LOC, Holt and colleagues
suggested that although there may be some similarity between the concept of
self-efficacy and internal LOC, self-efficacy does not appear to address issues
of external LOC to the same degree.
In considering the mechanisms of the association between LOC and weight-
related outcomes, a number of studies suggest that LOC may be related to indi-
viduals’ adherence to recommended behavioral and nutritional changes. For ex-
ample, Springer, Bogue, Arnold, Yankou, and Oakley (1994) found that healthy
dietary behavior was positively related to internal LOC, and there is some support
suggesting that individuals with an internal LOC are more likely to engage in
activities related to successful weight loss, weight loss maintenance, or both (for
a review, see Elfhag & Rösser, 2005).
In contrast to the research on adult LOC, weight loss, and adherence be-
haviors, very little research has addressed the association of parental LOC on
child weight loss. In one investigation of 49 families with children receiving
treatment for overweight, Favaro and Santonastaso (1995) found that mothers’
internal LOC as measured by Rotter’s (1966) I-E scale was unrelated to child
weight loss. Similarly, Kirschenbaum, Harris, and Tomarken (1984) examined
parental LOC as a predictor of child weight loss in a cognitive-behavioral
group treatment that involved both parents and children aged 9 to 13 years.
Consistent with Favaro and Santonastaso, general parent LOC did not predict
success throughout treatment or at the 1-year follow up.
Several significant limitations are evident in the small research literature
on LOC and children’s weight loss that perhaps explain these unimpressive
findings. First, the previous evaluations have been limited by the use of a
unidimensional measure of LOC (i.e., the Rotter, 1966, I-E scale). Second,
previous investigations of LOC and child weight management have used a
general measure of LOC, rather than a measure that assesses beliefs specific
to weight problems. In addition, these investigations focused only on parent’s
perceptions of their own general beliefs, not beliefs specifically related to their
child’s health.
With regard to the first limitation, some investigations suggest that the LOC
construct is more accurately measured with a multidimensional scale that in-
cludes internal LOC as well as external LOC influenced by chance, doctors,
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LOCUS OF CONTROL AND OVERWEIGHT 129
and powerful others (Wallston, Stein, & Smith, 1994; Wallston, Wallston, &
DeVellis, 1978). Based on findings from the adult literature on health promotion
behaviors (e.g., Christensen, Benotsch, Wiebe, & Lawton, 1995; Myers & Myers,
1999; Steptoe & Wardle, 2001), it is reasonable to expect a relation between
these subscales reflecting external LOC and the behavioral changes necessary
for weight loss in children.
With regard to the second limitation, a majority of previous research on
weight management has assessed general LOC using Rotter’s (1966) I-E scale
or the Multidimensional Health Locus of Control scale (Wallston et al., 1978)
that focuses on general health beliefs (i.e., not specific to weight). Rotter (1975)
theorized that situation- or condition-specific measurement of LOC would lead
to better prediction of behaviors or outcomes than a more generalized approach.
The goal of this study was to examine the associations between adherence to
treatment, treatment outcomes, and parent control beliefs regarding their child’s
overweight. To address these associations, this study employed a condition-
specific measure of parental health LOC for childhood overweight. The speci-
ficity of the measure was expected to yield a better understanding of whether
parents’ attitudes about pediatric overweight were related to adherence and,
ultimately, to success in treatment. Given the research findings that suggest
believing in someone may lead to increased adherence and outcomes (e.g.,
Poll & De-Nour, 1980; Read, Brunner, St. Jeor, Scott, & Carmody, 1991), it
was hypothesized that both internal and external components of parents’ health
LOC would be related to treatment outcomes. Specifically, parents with higher
internal, doctors, or powerful others scores were expected to have children with
improved treatment outcomes. High chance scores, in contrast, were expected
to be associated with the poorest outcomes.
The relation between parental LOC and specific measures of child adherence
has not been addressed in the research literature; therefore, this study is a
preliminary exploration of these relations. However, it was expected that the
findings would be similar to those hypothesized regarding treatment outcome.
Specifically, higher scores on internal, powerful others, or doctors subscales were
expected to be associated with higher levels of adherence. Conversely, higher
chance scores were expected to be related to lower levels of adherence.
METHOD
Participants
Participants were recruited from families who were self-referred to two clinics
in the Midwest offering a specific pediatric weight loss program provided by the
authors and affiliated clinic staff. Families were initially screened onsite, and 74
children were identified as meeting criteria for inclusion in this study. Inclusion
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130 ROSNO, STEELE, JOHNSTON, AYLWARD
criteria included (a) being designated overweight by treatment center staff (i.e.,
at least 10% overweight), (b) between the ages of 6 and 18 years, and (c)
having at least one parent willing to attend weekly sessions. Six children were
excluded from analyses due to a sibling or other close relative being targeted as
the identified patient. Five participants did not return questionnaires and were,
therefore, not included in the sample. Thus, the number of participating children
was 63, with a mean age of 11.6 years. On average, the participants began the
program at about the 99.1 body mass index (BMI) percentile for age and gender.
The sample was largely European American (83%), but also included partici-
pants who reported being African American (6%), Native American (4%), and
those reporting “other” ethnicities (8%). The participating guardians included
46 mothers, 11 fathers, 2 stepparents, and 4 described as “other.” Parents who
completed the measures provided information regarding their educational level.
As demonstrated in Table 1, most parents had completed either an associate’s
or bachelors degree. Complete descriptive statistics for the sample can be found
in Table 1.
TABLE 1
Demographic Information for the Sample
Variable n (%) M (SD)
Age 11.63 (2.49)
Child gender
Female 33 (52)
Male 30 (48)
Participating parent
Mother 46 (73)
Father 11 (18)
Other 6 (10)
Ethnicity
European American 45 (83)
Native American 2 (4)
African American 3 (6)
Other 4 (8)
Not reported 9
Parent education level
High school graduate 6 (11)
Attended some college 7 (13)
Completed junior college or associate’s degree 11 (20)
College graduate 10 (19)
Some post-graduate work 5 (9)
Graduate degree 14 (26)
Not reported 10
Body mass index percentile 99.12 (5.13)
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LOCUS OF CONTROL AND OVERWEIGHT 131
Intervention
Children and parents participated in a group-based family intervention for pedi-
atric overweight comprising 10 weekly sessions. The intervention was delivered
by two master’s level therapists under the supervision of a licensed doctoral
level psychologist. The intervention focused on three primary components: nu-
trition education, exercise education, and behavior modification. The program is
described in greater detail elsewhere (Johnston & Steele, 2007), and was based
on Epstein, Wing, Koeske, Andrasik, and Ossip’s (1981) Traffic Light Program
(TLP). The TLP has received perhaps the most empirical support in terms of
weight loss for children (e.g., Kazdin & Weisz, 1998) and has been shown to
have maintenance effects at 10 years post intervention (Epstein, Valoski, Wing,
& McCurley, 1990, 1994).
Specific behavioral treatment components included self-monitoring, praise
and modeling, reinforcement and contracting, and stimulus control, as described
later.
Self-monitoring. Participants were taught to monitor and record dietary
intake including the specific food eaten, the preparation of the food, and the size
of the serving. In addition, they were instructed in recording physical activity,
including intensity, duration, and frequency of exercise sessions and activities
of daily living. Parents and children were asked to review daily progress and
records.
Praise and modeling. Parents and children were instructed on the impor-
tance of setting an appropriate example for other family members with regard to
food intake, exercise, and so forth. In addition, family members were encouraged
to support and praise all progress by others. Specifically, parents and children
were trained to recognize and acknowledge positive healthy change in each
other.
Reinforcement and contracting. Parents were instructed to contract with
their children for reinforcers related to short-term goal attainment (i.e., weight
loss and habit change). Parents and children were encouraged to develop their
own individualized contracts. Reinforcements were encouraged to be activities
that promote further positive change such as taking family bike rides, going to
a park, or going swimming.
Stimulus control. Because the types of foods that are stored in the home
influence child food preferences, families were instructed to remove all “junk”
foods from their homes. In addition, parents and children were encouraged to
increase their intake of novel healthy foods (e.g., fruits and vegetables).
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132 ROSNO, STEELE, JOHNSTON, AYLWARD
Measures
Demographics. Demographic information including parents’ current mar-
ital status, level of education, height, presence of weight problem, and history
of weight problem was obtained from the parent. Parents also provided their
child’s ethnicity, the number of children currently in the home, and whether
other children in the home have a weight problem.
Anthopometric measures. Participants’ weights were measured using a
digital wall-mounted scale with participants wearing light clothing and no footwear.
Height was measured on a laboratory-constructed height board, again with no
footwear. BMI was calculated using the standard metric provided by the Centers
for Disease Control (CDC) and Prevention (2000; BMI D kg/m2� 10,000/:
A standardized BMI (z score) was used as the primary outcome measure for
the study. A BMI z score was used because of limitations inherent in the use of
raw BMI scores, particularly in child samples. Specifically, because of factors
such as onset of puberty, normal differences in adiposity, changes in height, and
the velocity of height change, BMI must be interpreted in the context of age and
gender. A BMI z score statistically adjusts for these factors and allows a direct
comparison of children of different ages and gender. The calculation of BMI
z scores was completed using CDC criteria (Kuczmarski et al., 2000). Week 1
weight and height were used for the initial standardized BMI. Week 10 weight
and height (or the last known measurements at termination of the program) were
used to calculate posttreatment standardized BMI.
Treatment adherence. Self-reported treatment adherence was calculated
across a number of dimensions of the intervention, including fruit and vegetable
intake, and caloric output. Average percentage of adherence for fruit and veg-
etable consumption and physical activity for the overall program was determined
by totaling each of the weekly percentages and dividing by the number of
weeks with available data. The two measures of percentages of adherence were
converted to standardized z scores and averaged to obtain one overall adherence
score for the self-report measures.
Attendance, record keeping, and home inventories were used to provide more
objective measures of adherence to the program. The percentage of sessions
attended was divided by the total number of sessions (i.e., 10) and multiplied by
100 to obtain the percentage of adherence for attendance. Next, the presence or
absence of record keeping was noted each week. Record keeping alone has been
shown to be a predictor of outcomes in weight loss treatment (e.g., Israel, Silver-
man, & Solotar, 1988). Parents and children were given the joint responsibility
of record keeping. In the cases where children were unable to keep records
(e.g., the children were too young), parents were responsible for completing
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LOCUS OF CONTROL AND OVERWEIGHT 133
self-monitoring records. Depending on each child’s ability, children were given
self-monitoring tasks to encourage active participation in their lifestyle change
(Israel, Stolmaker, & Andrian, 1985). The total number of weeks for which
records were kept was divided by the total weeks in attendance to determine a
percentage of adherence for record keeping. Because this information was used
during the actual intervention, children and parents were instructed to complete
these records before each weekly meeting. This information was collected by
the group facilitator.
Finally, an inventory of foods in the parent-identified food storage areas in
each participant’s home was taken by trained master’s level therapists prior to
treatment and at the end of treatment. Attention was given to the variety of
food types (e.g., snack chips, non-diet soda, green beans, grapes), rather than
the quantity of each type of food. All foods were then grouped into one of three
categories (i.e., red, yellow, or green) based on nutritional value as outlined by
Epstein et al. (1985): red (foods to be eaten sparingly; i.e., foods with >7 g
of fat or 12 g of sugar), yellow (foods to be eaten in moderate amounts), and
green (foods to be eaten without restriction; e.g., most fruits and vegetables).
This categorization system was used to correspond with the treatment being
delivered (the TLP).
This home inventory was reliable across the four trained staff members, with
95% interrater agreement for recorded foods in the home. Coding of foods
into green, yellow, and red categories was also highly reliable (average 91%
agreement across 5 cases). Given research indicating that decreasing unhealthy
food in the home is related to greater weight loss success (Epstein, McCurley,
Wing, & Valoski, 1990), the change in red foods was the primary variable used
in analyses. Specifically, the number of red foods at Time 2 was subtracted from
the number of red foods at Time 1 to achieve a change score.
LOC for child weight. The 18-item Multidimensional Health Locus of
Control–Form C (MHLC–C; Wallston et al., 1994) is a condition-specific mea-
sure of health LOC. The original measure was intended to assess adult health
LOC for a specific health condition. In each question, the words “my condition”
were replaced with the specific condition of interest (e.g., weight problems).
The original MHLC–C is comprised of four subscales corresponding to internal
(e.g., “I am directly responsible for my condition getting better or worse”),
external chance (e.g., “Luck plays a big part in determining how my condition
improves”), doctors (e.g., “If I see my doctor regularly, I am less likely to
have problems with my condition”), and powerful others (e.g., “In order for my
condition to improve, it is up to other people to see that the right things happen”).
Wallston and colleagues (1994) reported adequate internal consistency estimates
for the four subscales (Cronbach’s ˛ D :86 for the internal subscale, .80 for the
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134 ROSNO, STEELE, JOHNSTON, AYLWARD
chance subscale, .71 for the doctors subscale, and .70 for the powerful others
subscale).
For this study, the MHLC–C was adapted in two ways. First, the measure
was adapted to assess parents’ LOC for their children’s weight problem rather
than for their own weight problem. Second, because the questionnaire related to
the child’s weight problem rather than the adult’s, a second internal scale was
added: Six questions were added to assess the parent’s belief that the weight
problem was internal to the child. The original scales measured only internal
beliefs for the person filling out the questionnaire (i.e., the parent). For the
second internal scale, the wording of the items in the existing internal scale
(e.g., “I am directly responsible for my child’s weight problem getting better
or worse.”) was changed to reflect the responsibility being internal to the child
(e.g., “My child is directly responsible for his or her weight problem getting
better or worse.”). Cronbach’s alpha for each of the subscales in this study was
as follows: internal-parent, ˛ D :85I internal-child, ˛ D :85I chance, ˛ D :86I
doctors, ˛ D :70I powerful others, ˛ D :76:
Procedure
Children and their parents were enrolled in a pediatric weight loss program
that included nutrition education, exercise education, and behavior modification.
Treatment was received in a group-based format. A typical group consisted of 6
children and their parents. Because these were children who were self-initiated
referrals, groups were formed as children presented for treatment. To the extent
possible, groups were comprised of children of similar ages, with some leeway
allowing for rapid onset of treatment. Questionnaires including demographic
information and parental LOC were distributed prior to the first week of class
to be returned at the first class. Parental consent and child assent were obtained
before the first session. Prior to each session, parents’ and children’s weights
were recorded and self-report measures were collected. All procedures and
information gathered were part of the standard program protocol. Participating
in research did not alter the program requirements or benefits. This procedure
was approved by Human Subjects Committee (institutional review board) of the
investigators’ institution.
RESULTS
Preliminary Analyses
Prior to addressing the primary study questions, the associations of study vari-
ables (e.g., LOC, adherence, BMI z score change) to demographic variables
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LOCUS OF CONTROL AND OVERWEIGHT 135
were examined. Pearson’s correlations were conducted between the continuous
demographic variables (i.e., child age and initial BMI z score) and LOC vari-
ables. Internal-child ratings by parents were found to be positively correlated
with child age, r.52/ D :35; p < :01: Specifically, parents of older children
were more likely to describe the child’s weight problem as internal to the child.
No other scales of the MHLC–C were significantly related to child age. Further,
the LOC scales were not significantly related to the participant’s initial BMI
z score.
Next, independent samples t tests were conducted to examine categorical
variables (i.e., child gender and parent gender) in relation to the dependent
variables. No difference in LOC was found for parent gender. Regarding child
gender, parents rated doctors as more important for male children when com-
pared to female children t.58/ D 5:33; p < :05: There were no significant
effects for child gender with the other LOC scales. Finally, a multivariate
analysis of variance with parental education level as the independent variable,
and each of the LOC subscales as the dependent variables indicated that parental
education level was not associated with LOC: Wilks’s � D :72; F.25; 161/ D
0:61; p > .50. No other significant associations between demographic variables
and study variables were identified.
LOC and Treatment Outcome
To examine the association between LOC and treatment outcome, a hierarchical
multiple regression analysis was performed with change in BMI z score (i.e.,
initial BMI z score minus final BMI z score) entered as the dependent variable.
Age was entered as a control variable on the first step of the equation, and
the five LOC scales were entered as independent variables on the second step.
Step 2 of the model was significant, F.5; 43/ D 2:50; p < :05; and indicated
that the powerful others scale and chance scale were significant predictors of
outcomes. Specifically, higher powerful others ratings and lower chance ratings
were predictive of greater change in BMI z score. The internal-parent scale of
the LOC measure approached significance .p D :08/; but not in the direction
that was hypothesized (see Table 2).
LOC and Adherence
To examine the association between LOC and adherence to treatment, a series
of Pearson correlations were calculated, using the four indexes of adherence
(self-report, attendance, record keeping, and observed changes in red foods
present in the home) and the five LOC subscales. Three significant relations
were identified. First, child attendance to sessions was found to be signifi-
cantly and inversely related to scores on the chance scale of the health LOC
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136 ROSNO, STEELE, JOHNSTON, AYLWARD
TABLE 2
Hierarchical Multiple Regression Analyses Results for Locus of Control Predicting Change
in BMI z Score
Variable B SE B ˇ �R2 �F
Step 1 .041 2.061
Child age �.001 .001 �.203
Step 2 .216 2.501*
Child age �.001 .001 �.184
Internal-parent �.005 .003 �.254***
Internal-child .005 .003 .207
Powerful others .015 .006 .436**
Doctors �.002 .005 �.061
Chance �.008 .004 �.323*
*p < :05: **p < :01: ***p < :10:
measure, r.58/ D �:34; p < :01: Specifically, parents who rated the child’s
weight problem as being due to chance had children who attended sessions
less frequently. Second, internal-parent ratings were negatively correlated with
attendance, r.60/ D �:27; p < :05; such that parents who felt they were more
responsible for the child’s weight problem attended fewer sessions. Third, change
in red foods in the home was positively correlated to parents’ internal-child
ratings, r.36/ D :44; p < :01: Parents who indicated that the child was more
responsible for his or her weight problem had greater decreases in the number
of red foods at the end of treatment. No other correlations between treatment
adherence and LOC variables were significant.
DISCUSSION
Throughout the literature on the treatment of pediatric overweight, parents are
recognized as key partners for success (e.g., Epstein et al., 1985). However,
research attempting to systematically evaluate the specific parental factors that
may impact adherence and outcomes in treating pediatric overweight remains
lacking. The goal of this study was to examine the relation of parents’ social
cognitive variables with child adherence and outcomes in treatment. Specifi-
cally, parents’ health LOC was explored as a potential factor influencing child
adherence and outcomes in family-based treatment for pediatric overweight.
Regarding parents’ LOC for child weight problems, it was expected that
parents endorsing greater confidence in internal factors or in other professionals
would have children with greater levels of adherence and success in treatment.
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LOCUS OF CONTROL AND OVERWEIGHT 137
By contrast, those parents who reported that their child’s weight was due to
chance were expected to have children who were less adherent and have less
significant treatment gains.
The hypotheses regarding parents’ LOC were partially supported. As ex-
pected, higher powerful others scores were related to improved treatment out-
comes. This finding was consistent with previous studies linking the powerful
others scale to health behaviors such as taking vitamin supplements and adhering
to cystic fibrosis and diabetes treatment (Christensen et al., 1995; Myers &
Myers, 1999; Read et al., 1991). The association between belief in powerful
other people and treatment outcome is significant, given the prominent role that
professionals play in facilitating treatment. This study suggests that parents who
place confidence in powerful others such as treatment providers have children
who are more successful in treatment. Perhaps more confidence in powerful
others indicates a greater willingness on the part of parents to accept and
implement professional recommendations that a structured treatment program
provides.
Previous research has provided strong support for the relation between in-
ternal LOC and health outcomes (e.g., Kelly et al., 1990; Silverman et al.,
1986), but research had not addressed parents’ perceptions of their own con-
trol separate from control internal to the child. It was hypothesized that both
internal-child and internal-parent scores would be predictive of positive treatment
outcomes. Regarding internal-parent, the finding approached significance, but in
the opposite direction. Parents who rated themselves as more responsible for the
child’s weight problem had children with marginally less successful outcomes
in treatment. Further, parents who rated themselves as more responsible for
the child’s weight problem had children with significantly poorer attendance.
Although unanticipated in this study, the combination of low internal scores
with high powerful other scores was also found to be predictive of adult health
behaviors by Christensen and colleagues (1995). Again, parents who place more
confidence in others such as treatment providers may be more likely to be open
to treatment recommendations than those who feel responsible for treatment
themselves.
A second potential explanation for the inverse relation between parent-internal
scores and child outcomes is that parents who feel overly responsible for their
child’s weight problem may inadvertently exhibit control behaviors that are
counter-productive to treatment. Several studies have found that excessive parental
control in relation to child eating behavior may have negative effects on weight
status and healthy eating behavior. Specifically, children who receive more
external cues from parents (e.g., verbal prompts, pressure to eat certain foods,
etc.) tend to show a diminished ability to self-regulate eating behaviors, as well
as greater levels of adiposity (Birch, McPhee, Shoba, Steinberg, & Krehbiel,
1987; Fisher & Birch, 1999a; Johnson & Birch, 1994).
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138 ROSNO, STEELE, JOHNSTON, AYLWARD
Guided by research on parental involvement in the treatment of pediatric
overweight (e.g., Epstein, 1996; Golan & Weizman, 2001), parents in this
study were encouraged to take an indirect role in the child’s treatment while
children were urged to accept responsibility for healthy choices. Specifically,
parents were asked to provide praise and reinforcement, model healthy lifestyle
behavior, and assist with stimulus control (i.e., grocery shopping, food prepa-
ration). Furthermore, parents were discouraged from engaging in the strict
management of the child’s eating choices and physical activity. The inverse
relation between internal-parent scores and child outcomes may reflect that
this form of “micromanagement” of child behavior is, in fact, harmful for
treatment.
It is interesting to note that these data indicate that higher internal-child scores
are associated with greater decreases in red foods posttreatment. Given the level
of parental responsibility for grocery shopping, one would expect parent control
to have a greater impact on stimulus control in the home when compared to
child control. Perhaps this finding can be related to the previously mentioned
studies linking excessive parental control to negative outcomes. For example,
parents who view the child as responsible for his or her weight problem and
for amending the problem may be more likely to give the child the freedom
within the home to make his or her own choices. However, parents may take
the responsibility of ensuring that fewer unhealthy choices exist in the home,
thus providing a “safety net” of sorts. Likewise, parents who do not perceive the
child as playing a critical role in the weight problem and its treatment may be
engaging in controlling, restrictive practices that may hamper the child’s ability
to develop healthy habits for him or herself.
Although the chance scale on the LOC measure was not significantly related
to child outcomes as expected, it was significantly correlated with session at-
tendance. Specifically, parents who endorsed stronger beliefs that chance and
fate were responsible for the child’s weight problem had children that attended
fewer weekly sessions. Although the results of the regression analysis suggest
that higher chance scores did not result in less success in the program, session
attendance was positively related to outcomes. Previous research supports the
link between lower attendance and decreased outcomes in weight management
programs (e.g., Carels, Cacciapaglia, Douglass, Rydin, & O’Brien, 2003; Chao
et al., 2000).
Although this study provides a number of contributions to the literature,
several limitations exist that may restrict the generalizability of the findings.
First, due to the relatively small sample size, the statistical power was limited
in some analyses, therefore decreasing the likelihood of detecting significant
findings. Also, the sample was comprised primarily of European American,
middle class participants. Several obstacles prevented obtaining a larger, more
diverse sample.
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LOCUS OF CONTROL AND OVERWEIGHT 139
Although research in applied clinical settings has many benefits, it also
presents challenges. In this study, the treatment provided was not without ex-
pense to the participants. Given the multidisciplinary nature of the treatment,
the cost for service provision may have hindered some from lower income
strata from seeking treatment. Correspondingly, the educational attainment of
participating parents was quite high. These factors perhaps compromise the
generalizability of these findings to families from lower socioeconomic strata
and those with fewer years of formal education. Future research would benefit
from exploring treatment options available to a wider range of socioeconomic
and ethnic groups. Such research is important because of increases in pediatric
overweight among minority youth (Mirza et al., 2004; Ogden et al., 2006), the
higher attrition rates among African American participants seeking treatment
for overweight (Zeller et al., 2004), and demonstrated differences in children’s
health LOC scores across ethnic groups (Malcarne, Drahota, & Hamilton, 2005).
Finally, this study was limited by its reliance on parent-reported LOC for child
weight issues. Additional studies utilizing child-report measures of health LOC
will be important both to examine the development of the construct in children
and youth, and as a predictor of adherence to behavioral health interventions.
Implications for Research
Despite limitations in this study, these results offer initial evidence for the
role of parents’ LOC in relation to treatment. Although replications of these
findings are necessary, preliminary support has been provided for the use of
condition-specific measures of LOC in studies of pediatric overweight treatment.
Furthermore, this study demonstrates the importance of using a multidimen-
sional measure of LOC. The findings regarding the unique role of powerful
others, chance, and internal-parent scales suggest that use of the unidimensional
measures of this construct would not adequately capture these distinctions.
The findings of this study demonstrate the potential value of exploring the
influence of the social cognitive variables of others close to the primary target of
treatment. In other words, in treatments that require extensive lifestyle changes
and social support, the success of the treatments may be influenced by the
beliefs of significant people other than the patient. Previously, research had not
attempted to examine attitudes of parents or others close to the targeted patient
in relation to adherence and treatment outcomes. Future studies are necessary
to clarify how parents and others may assist or hinder treatment.
Implications for Practice
To the extent that child control of weight-regulating behaviors is the alter-
native to parent control, these data speak to the importance of attending to
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140 ROSNO, STEELE, JOHNSTON, AYLWARD
developmentally appropriate child autonomy in treatment programs. Specifically,
programs that emphasize an indirect role for parents and encourage children and
adolescents to assume an active role in making lifestyle changes may be most
beneficial in treating pediatric overweight. Indeed, evidence suggests that some
forms of parental control vis-à-vis food and diet are associated with poorer
outcomes in terms of food consumption, food preference, and evaluation of
and responsiveness to satiety cues (e.g., Birch, Fisher, & Davison, 2003; Fisher
& Birch, 1999a, 1999b), although some reports to the contrary have recently
emerged (for a review, see Faith & Kerns, 2005).
Further, our results suggest that there may be some benefit to prescreening
potential clients on LOC variables that predict poorer outcome or adherence.
Families endorsing high parent-internal or high chance beliefs may benefit from
education regarding the role of various family members in behavioral strategies
for weight management. A program module designed to educate parents about
effective treatment components, as well as the potential gains that can be made
from such treatment may better prepare families to be successful in meeting
their weight management goals. Other authors (e.g., Israel et al., 1985) have
suggested similar “add-on” modules to tailor weight management programs
to families’ specific needs. Beliefs regarding LOC have been shown to be
malleable to intervention (e.g., Rybarczyk, DeMarco, DeLaCruz, & Lapidos,
1999). Whether changes in LOC will directly translate into treatment effects has
yet to be demonstrated.
In summary, this study provided preliminary support for the notion that
parents’ social cognitive variables are related to the treatment of pediatric over-
weight. Specifically, children were most successful in treatment when parents
endorsed a strong belief in powerful others such as treatment providers and
a belief that they (parents) were less responsible for the weight problem and
its treatment. In addition, children had lower attendance rates when parents
reported that chance and factors internal to parents were major determinants
in child weight problems and treatment. These findings provide support for
family-based treatments that encourage parents to take an active but indirect
role in treatment while encouraging children and adolescents to be responsible
for making positive choices regarding their health. Further research into the role
of parental beliefs and behaviors in relation to pediatric obesity will aid in the
continued development of effective treatment programs to counter the alarming
rates of child and adolescent overweight.
ACKNOWLEDGMENT
This research was funded by a grant (KAN30472) from the Kansas Health and
Nutrition Fund, awarded to Ric G. Steele.
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LOCUS OF CONTROL AND OVERWEIGHT 141
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