Pediatric Weight Management

PWM: Individual Child Counseling (2006)

Citation:

Kirschenbaum DS, Harris ES, Tomarken AJ. Effects of parental involvement in behavioral weight loss therapy for preadolescents. Behavior Therapy 1984;15:485-500.

 

 
Study Design:
Randomized Controlled Trial
Class:
A - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To examine the effects of parental involvement and family environment on weight loss in obese preadolescents.

Inclusion Criteria:

Children:

  • age 9-13 years
  • literate
  • >20% overweight relative to norms for height, weight, age & sex.

Parents:

  • >10% overweight relative to norms for height, weight, age & sex (Metropolitan Life Insurance, 1959).

Children and Parents:

  • eagerness to participate expressed in written & oral responses in pretreatment interviews
  • expressed willingness to increase levels of exercise
  • physician’s written permission to participate in the program
  • no involvement in other weight reduction program or psychotherapy
  • expressed willingness to work together.
Exclusion Criteria:
  • Children with learning disabilities
  • Children who began treatment programs late.

 

Description of Study Protocol:

Recruitment

  • Using the following methods, advertised as weight reduction program with at least one overweight parent willing to participate
    • Newspaper, radio and television advertisements
    • Posters
    • Stories.

Study design Randomized, controlled trial 

Intervention

  • All treatment groups met for nine weekly, 90-minute treatment sessions plus three month and one year follow-up assessments.
  • Subjects in treatment groups were charged a $30 fee plus a $50 deposit payable at the first session. Deposits were refunded contingent on attendance ($2 per treatment session. $5 for 3 month and $13 for 1-year follow-up) and at least partial completion of homework assignments ($2 per treatment sessions).
  • Cognitive-behavioral treatment program included: Self-monitoring of foods eaten, time, place and mood, graphing and increasing levels of exercise, nutrition education, stimulus control, planning of meals and exercise, self-reward, decelerated eating and coping techniques such as cognitive strategies for managing negative self-statements, assertion training and relaxation training.
  • Treatment Groups:
    • Randomized to one of the treatment groups but not control group
      • Matched on the following:
        • Parent and child sex
        • Child age
        • Parent and child initial percentage of overweight.
    • Parent-plus-child condition
      • Both parent and child attended all sessions together.
      • Emphasized the importance of parent and child working together and asked parent to read and discuss each lesson with their child.
    • Child-only condition
      • Only the child attended the session.
      • Exactly the same material was covered in the same order as in the parent-plus-child groups.
      • Emphasized the child becoming the "expert" and teaching their parents about each week's lesson.
      • Required to bring in parent's homework assignments each week.
    • Waiting list control condition:
      • Subjects applying after the program started and began one month after the treatment began.

Statistical analysis

  • Analysis of variance
  • Analysis of covariance
  • Neuman-Keuls
  • Pearson product-moment correlation
  • Dropouts not included in final analyses.
Data Collection Summary:

Timing of Measurements

  • Pretreatment (baseline): All groups including control
    • Child's heighrt and weight
    • Parent's height and weight
    • Family environment questionnaires (parent only)
    • Locus of control scales (external vs internal): completed by both parent and child
    • Motivation and expectancy scales by both parent and child
  • Posttreatment (end of 9 week period): All groups including control
    • Same as above
  • Three month follow up
    • Same as above
  • One year follow up: Only two treatment groups
    • Same as above.

Dependent Variables

  • Weight-related measures
    • Child adjusted weight (adjusts children’s weight for estimated average growth in height and weight, Edwards, 1978))
    • Parent's percent overweight based on 1959 Metropolitian Life Insurance tables
    • Child's percent overweight based on weight/height norms given (Edwards, 1978)
    • Weight reduction index for both children and parents (Feinstein, 1959).
  • Family environment (Moos Family Environment Scale – Factor 1 (Liberalism), Factor 2 (Competitiveness), Factor 3 (Chaos), Factor 4 (Religiousness).
  • Locus of control.
  • Parent and child motivation and expectancy.

 Independent Variable

  • Treatment Group (see study protocol above).

Control Variables

  • Parent and child sex
  • Child age
  • Parent and child initial percentage of overweight

 

Description of Actual Data Sample:

Initial N: 40 subjects

  • Child + Parent: N=16
  • Child only: N=15
  • Control: N=9.

Attrition (final N):

  • Child + Parent: N=13
    • Children: 3 male/10 female
    • Parents: 2 male/11 female.
  • Child only: N=9
    • Children: 2 male/7 female
    • Parents: 1 male/8 female.
  • Control: N=8
    • Children: 2 male/6 female
    • Parents: 2 male/6 female.
  • Reasons for withdrawal
    • Parental dissatisfaction at being assigned to the child only group: N=3
    • Medical reasons (broken leg, phlebitis): N=2
    • Unavailable for follow up: N=1
    • Learning disability not detected during screening and unable to follow program: N=1
    • Initiated treatment 2 weeks late: N=1.

Age: see table

Ethnicity: not specified

Other relevant demographics: not specified.

Anthropometrics: see table

 Mean±SD for parameters below

  Parent + Child Child Only Control
Age (child), years 10.4±1.0 11.2±1.0 10.5±1.4
Weight, kg                         
Children 55.8±13.7 52.3±19.7 52.1±16.6
Parents 79.4±21.2  78.5±15.8 89.7±18.2
Percent Overweight      
Children 58.1±26.2 39±18.4 42.4±20.4
Parent 36.0±29.4 37.7±30.5 47.0±24.5

Groups did not differ significantly on any of the weight measures at pretreatment.

Location: Madison, Wisconsin

 

Summary of Results:

Weight-Related Measures

  1. Both parents and children in the treatment groups lost more weight during the program than dyads in the control group (P<0.01).
  2. The parent-plus-child and child-only treatment groups did not differ from each other, nor did parents and children within any of the groups change differentially at the post-treatment assessment.
  3. Children in both treatment groups retained their improved weight loss at three-month follow-up compared to control group children (P<0.01), who in fact gained a significant amount of weight from their baseline levels.
  4. Parents in the parent-plus-child group sustained greater weight reduction at the three month follow up than parents in either the child-only group (P<0.01) or the control group (P<0.01).
  5. By the three-month follow-up, the parents in the child-only group had regained so much weight that they became comparable to controls.
  6. Children in both treatment groups sustained their initial and similar degree of weight loss (nonsignificant), while parents in the parent plus child group again better sustained their initial weight loss at the one year follow up than paprents in the child only group (<0.02).
  7. Analysis of the percentage overweight data and the parent weight and child adjusted weight data yielded essentially the same findings as analyses of the weight reduction indices.

 Mean±SD

  Parent + Child Child only Control
Children's Weight (kg)      
Posttreatment 53.7±13.2 49.6±8.3 52.3±17.1
Three month follow up 54.2±13.8 49.2±7.8 53.6±17.0
One year follow up 52.6±13.5 49.5±7.9  
Parent's Weight (kg)      
Posttreatment 75.8±20.7 75.7±15.3 90.2±19.0
Three month follow up 75.8±20.6 77.9±15.2 91.4±18.6
One year follow up 73.2±14.7 78.3±15.3  

Within (child-parent) dyad correlations

  1. Improved weight reduction indices by children were positively correlated with improvement by their parents for the those in the parent plus child group at the one-year follow-up (P<0.05).
  2. Improvement by children in the child-only group was negatively correlated with improvement by their parents at the one-year follow-up (P<0.01).
  3. Child and parent improvement were not significantly correlated in the waiting list control group.
  4. Correlation between children and parents in the parent plus child group were significantly more positive than those in the child-only grou at both the three month (P<0.02) and one year follow up (P<0.002).

Family Environment

  1. Both the parent-plus-child group and the child-only group showed more improvement in the Liberalism qualities (reported family cohesion, mutual support, and open expression of feelings) than the control group (P<0.05). However, by the three-month follow-up these differences had disappeared.
  2. There were no significant findings on the other three family environment scale factors.

Locus of Control

  1. Children in the child only group became more internal at the three month follow up than children in the parent plus child group (P<0.03), but this difference was not sustained at the one year follow up.

Predictors of Outcomes

  1. Families which reported rather chaotic family environments (scored high on the Moos Family Environment Scale Chaos Factor) were more likely to drop out of treatment than families with reported less chaotic environments (P<0.004)

Weight change

  1. Children from families that scored high on Liberalism Factor lost relatively less weight than those whose families scored low on this factor both at post-treatment (P<0.02)  and three-month follow-up (P<0.001).
  2. Children whose participating parent had a relatively late onset of obesity lost more weight at post-treatment than those whose parent had an early onset of obesity P<0.05).
  3. Childen who felt that it was very important for them to lose weight lost less weight at three-month follow-up than those who felt that losing weight was not as important P<0.05).
  4. Those parents who initially indicated on the pre-treatment questionnaire that they had the least amount of control over losing weight lost the most weight at one-year follow-up P<0.02).

Other findings

  • Attrition
    • Parent + Child Group: 81% were available for one year follow up
    • Child Only Group: 60% were available for one year follow up
    • Control Group: 89% available at the three month follow up.
Author Conclusion:

The strongly negative intradyad weight loss correlation in the child-only group, in contrast to the positive correlation in the parent-plus-child group, also lends support to the hypothesis that the family environment may importantly affect treatment of childhood obesity.

Overall, the weight reductions achieved during treatment by children in treatment groups (6.1%) are comparable to reductions produced in other behavioral programs of similar duration and intensity and are clearly superior to controls who usually gain weight. Small weight losses in preadolescent children may produce some clinically important long-term benefits, in part, due to physiological concomitants, although programs of longer duration may accentuate them.

Funding Source:
Government: NIH
University/Hospital: University of Wisconsin-Madison
Reviewer Comments:

Strengths

  • Tested 2 treatment groups
  • Matched on child & parent’s sex.

 

Limitations

  • Relatively small sample size.
  • Unclear whether the control group was part of the original design or created after recruitment began due to group matching difficulty or response to recruitment. Assignment to the control group was not random as it was to the treatment groups.
  • Section describing statistical analyses and models was not included. Inferred from results section.
  • Baseline data presented only for subjects completing the trial not the original sample.
  • High drop out rate in the child only group compared to treatment and control groups.
  • No data reported for attendance during the nine week treatment period.
Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) Yes
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? Yes
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
 
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? ???
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) No
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? ???
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? N/A
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? ???
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? Yes
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? No
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) Yes
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? N/A
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? Yes
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? N/A
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? Yes
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? ???
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments described? N/A
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? N/A
  6.8. In diagnostic study, were details of test administration and replication sufficient? N/A
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? No
  7.2. Were nutrition measures appropriate to question and outcomes of concern? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? Yes
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? Yes
  7.5. Was the measurement of effect at an appropriate level of precision? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? Yes
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? Yes
  8.1. Were statistical analyses adequately described and the results reported appropriately? No
  8.2. Were correct statistical tests used and assumptions of test not violated? Yes
  8.3. Were statistics reported with levels of significance and/or confidence intervals? Yes
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? No
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? No
  8.6. Was clinical significance as well as statistical significance reported? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? No
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? Yes
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes