Pediatric Weight Management

PWM: Individual Child Counseling (2006)

Citation:

Brownell KD, Kelman JH, Stunkard AJ. Treatment of obese children with and without their mothers: changes in weight and blood pressure. Pediatrics 1983; 71: 515-23.

PubMed ID: 6835735
 
Study Design:
Randomized Controlled Trial
Class:
A - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

To test 3 methods of parent involvement in the treatment of obese adolescents aged 12 and 16 years. Short-term and long-term changes in weight and blood pressure were assessed at the end of a 16-week treatment period and at the end of a 1-year follow-up.

Inclusion Criteria:

Subjects:

  • weighed at least 20% more than the average weight for age, sex & height.
  • were free of medical conditions or medications that would influence body weight
  • were not involved in other formal weight loss programs
  • were able to attend all sessions with their mothers

Mothers could be of any weight.

Exclusion Criteria:

not specified.

Description of Study Protocol:

Each parent deposited $15, $10 of which was refunded if both mother and child attended all sessions during the treatment phase. The remaining $5 was refunded for attendance at the follow-up meetings. In addition, the mothers paid a $3 fee before each meeting. As an incentive for the children, each child deposited $8 at the start of each month during treatment; $2 was returned to the child each week he or she lost 1 lb or more. All children received the same treatment, with the exception of parental involvement. The program was administered in weekly sessions of 45 to 60 minutes for a 16-week treatment phase.

All subjects received a program of:

  • behavior modification,
  • nutrition education (included info on basic food groups, maintaining a balanced diet low in sugar, salt and fat, specific methods for buying, preparing, storing and serving food & misconceptions about diet and nutrition--specific dietary intervention not described),
  • exercise instruction
  • social support.

After treatment ended, follow-up sessions were held every 2 months during the 1-year maintenance period.

Treatment Groups

Mother-Child Separately – children & mothers attended separate groups

Mother-Child Together – the children & mothers met together in the same group

Child Alone – the children met in groups, mothers were not involved

Data Collection Summary:

Dependent

Weight Change – Body weight, % above average weight, BMI, & new index, Developmental Index, which accounts for developmental growth (measured ht & wt following standardize procedure); Blood Pressure (measured).

Independent

Intervention Group (See Study Protocol above)

Control Variables

Gender & Tested for effects of cohort (2 different cohorts), experimental conditions & their interactions.

Statistical Analysis

Analysis of Covariance & Duncan’s Multiple Range Test.

Description of Actual Data Sample:

Original Sample: 42 obese adolescents, aged 12 to 16 years.

Withdrawals/Drop-Outs: not specified.

Final Sample: attrition rate was 10% at 16 weeks & 14% at the 1-year follow-up.

Location: Williamsport, Pennsylvania.

Race/Ethnicity: all white

SES: lower-middle class

Summary of Results:

The 3 groups within each cohort did not differ significantly in initial weight, % overweight, or BMI. Similarly, the two cohorts did not differ significantly on these measures or in changes in any of the four measures of weight loss.

Initial Weight Loss

The Mother-Child Separately group lost more weight (8.4 kg) during treatment than did the other two groups, Mother-Child Together & Child Alone groups (5.3 & 3.3 kg). Between group differences statistically significant (p<.01).

The Mother-Child Separately group showed sig. greater changes in % overweight than did the other two groups (p<.03), which in turn did not differ from each other.  The Development Index and BMI revealed similar results.

Long-Term Weight Changes

Differences between the groups increased at 1 year follow-up (p<.01): compared to pretreatment weight, the Mother-Child Separately group lost 7.7 kg compared to gains of approximately 3 kg above baseline weight in the other two groups. Because of increases in height, these latter two groups maintained their posttreatment degree of obesity despite the gains in weight.

There were also sig. treatment effects among the 3 groups for change in % overweight (p<.05) and change in weight. The results from the BMI & the Developmental Index agreed with the data from the other measure.

Correlation analysis revealed that age & initial weight were related to weight loss. Older children & heavier children tended to have greatest reductions in their degree of obesity.

Change in Mothers’ Weight

The correlations between mother & child changes in weight & % overweight were not sig. at the end of treatment or at follow-up.

Blood Pressure

BP of children with highest initial pressures decreased by 16/9 mm Hg at the end of treatment and by 16/5 mm Hg at the 1-year follow-up.

Author Conclusion:

There are four primary findings in this study:

  1. the nature of parent involvement may be as important as its presence or absence,
  2. a behavioral program with involvement of mothers can produce large weight losses and can sustain the losses for as long as 1 year after treatment,
  3. weight changes in the children are not associated with weight changes in mothers, and
  4. weight losses in obese adolescents are associated with significant decreases in blood pressure, particularly in children with the highest initial blood pressures.
Funding Source:
Government: NIMH, NHLBI
University/Hospital: Universtiy of Pennsylvania
Reviewer Comments:

Strengths

Children were ranked according to % overweight & then assigned randomly from stratified blocks to one of three experimental conditions.

Limitations

Small sample size.

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? N/A
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? N/A
  1.3. Were the target population and setting specified? N/A
2. Was the selection of study subjects/patients free from bias? N/A
  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? No
3. Were study groups comparable? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) Yes
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? Yes
  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? No
  4.1. Were follow-up methods described and the same for all groups? No
  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%.) No
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? No
  4.4. Were reasons for withdrawals similar across groups? No
  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? No
  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.) No
  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? N/A
  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? No
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? Yes
  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? Yes
  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? Yes
  7.2. Were nutrition measures appropriate to question and outcomes of concern? No
  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? No
  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? Yes
  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? N/A
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? No
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