PWM: Prescribed Diet Plan and Nutrition Education (2006)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To determine the effects of adding problem-solving training for parents and children or children alone to a comprehensive family-based behavioral childhood obesity treatment. Also to provide information on the long-term changes in child psychological problems in children provided family-based behavioral weight-control treatment.
Inclusion Criteria:
  1. Child >20% OW (based on 50th BMI percentile of Must, 1991)
  2. Neither parent >100% OW (same standard reference as above)
  3. 1 parent willing to attend meetings
  4. No family member on alternative weight control program
  5. No child/parent having current psychiatric problems
  6. No activity restriction on participating parent or child
  7. Child reading at >=3rd grade level
Exclusion Criteria:
None specified
Description of Study Protocol:

Family Recruitment

Recruited through newspapers, posters, previous participants and referrals by physicians.

Family Randomization (method not described) Stratified by gender and degree of child and parental obesity to the following groups:

  1. Problem solving taught to parent & child
  2. Problem solving taught to child
  3. Standard treatment without problem solving (control)

 

Treatment

  • Meetings – Weekly meetings for 4 mo + 2 monthly meetings thereafter; parents and children weighed and counseled together by a therapist  (15-30 min) and then attended separate group meetings for parents or children (30 min) and provided workbooks to take home.
  • Diet –  ‘Traffic Light Diet’ to reduce energy intake of children and OW parents to 1200 kcals/d, adjusted upward if lost weight too rapidly and given maintenance calorie level (involved increasing in 100-kcal/wk increments until gained weightt) when in nonOW range; nonOW parents had no calorie restriction, but asked to reduce ‘red foods’ and increase PA
  • Physical activity – lifestyle activities (workbook; not otherwise described)
  • Behavioral principles
    • Preplanning
    • Self-monitoring
    • Stimulus control
    • Positive reinforcement (e.g., parents deposited $75 which was returned if completed ¾ treatment sessions and attended 6- & 12-mo follow-ups; paid $50 for attending 24-mo followup)
  • Problem-solving –  integrated into other training
    • Didactic training  in group meetings
    • Used in group and individual sessions when question asked
    • Worksheets and homework
Data Collection Summary:

Dependent

  • Obesity (>20% overweight based on 50th BMI percentile)
  • BMI (Z scores for children) [all measured except for 5 children & 3 parents at 24 mo followup, in which case self-reported data were adjusted for underestimation of weight and overestimation of height based on a previously developed regression equation)
  • Child psychological problems (Child Behavior Checklist for Total Competence, Total Behavior Problems, Internalizing Behavior Problems, and Externalizing Behavior Problems)
  • Parent psychological problems (Symptom Checklist –90)
  • Use of behaviors related to weight control (Adherence questionnaire, 25-items, lab-constructed – at 24 mo only?)

Independent  (See description above)

  • Child problem-solving (assessed by Purdue elementary Problem Solving Inventory)
  • ± Parent problem-solving (assessed by Problem Solving Inventory Form B) 

Control Variables 

Age, gender, and initial BMI z score in some analyses (see below)

Statistical Analysis

  • 1-way ANOVA – for between-group differences at baseline and differences between treatment completers and noncompleters (intent to treat analysis)
  • Linear, quadratic, and cubic functions – for comparisons over 4 time points
  • Interactions tests – 2 single-degree-of-freedom contrasts of Group X Time comparisons
  • Chi-square tests – for psychological changes (too few elevated scores to do analysis by group)
  • Logistic regression – to test for clinically relevant changes in BMI z score (considered to be those children who reduced BMI z scores by >1 SD) by group, age, gender, and initial BMI z score

Univariate & multivariate relationships examined between gender, age, baseline BMI z score, and baseline and 2-year changes for child psychological problems, adherence and child and parent problem solving.

Description of Actual Data Sample:

Original Sample: 398 families expressed interest, 162 families screened, 67 met entrance criteria

Withdrawals/Drop-Outs:

3 decided not to participate before treatment began

1 parent died during treatment

1 child began taking steroids for an unrelated medical problem during treatment

Attrition:  3%, 11%, and 15% at 6, 12 and 24 mo, respectively

Final Sample:

62 parents (mean = 40.4 years), 62 children (mean = 10.3 years)

Note:  in table only refer to 52:  17 Gp 1, 18 Gp 2, 17 Gp 3)

Location:  Buffalo, NY

Duration:  24 mo:  6 mo treatment + 12 & 24 mo follow-up

Race/Ethnicity:  97% White, 2% Black, 2% Hispanic

SES:  Not specified

Summary of Results:

Baseline

  • Children - No differences between groups who began treatment & no differences between study completers and non-completers on gender, age, height, weight, BMI Z score, problem-solving, psychological problems or adherence
  • Parents - No differences between groups who began treatment & no differences between study completers and non-completers on gender, age, height, weight, problem-solving, psychological problems or adherence

Child Changes

  • BMI z score – No difference between groups at 6 mo (all decreased – Gp 1 2.8 to 1.5, Gp 2 2.6 to 1.2, Gp 3 2.7 to 1.2), but at 24 mo Gp 1 (2.3 ± 1.1) > Gps 2 (1.7 ± 0.9)  & 3 (1.6 ± 1.0) (p<.005)
  • Only group was a significant predictor at 24 mo of children who lost >1 BMI z-score unit (p<.02)
  • Gp 2 (50%, p<.02) and Gp 3 (47%, p<.03) had a greater % of children with large BMI decreased than did Gp 1 (11%)

Problem solving

  • No differences between groups
  • Increased in all groups at 6, 12 and 24 mo (p<.025)

Psychological  problems

  • No differences between groups
  • Decrease in all groups (Total Behavioral Problems from 16% at baseline to 4% at 24 mo, p<.05; Internalizing Behavior Problems from 16% at baseline to 0% at 24 mo, p<.005)

Adherence to treatment

  • No differences between groups

Relationships among variables

  • Child BMI change related only to baseline Total Problems and change in Total Problems (r=.53, p<.001)
  • Change in child problem solving related to baseline problem solving and changes in child competence (r=.62, p<.001)

Parent Changes

Weight

  • No difference between groups (all decreased at 6 mo [p<.001] – Gp 1 89.0 to 77.2 kg, Gp 2 79.8 to 68.7 kg, Gp 3 87.0 to 77.7 kg), and then went back up by 24 mo – Gp 1 (83.0 ± 17.4), Gp 2 (73.5 ± 15.4)  & 3 (84.7 ± 23.3))

Problem solving

  • Gp 1 showed greater increase than Gp 3 (p<.05)

Psychological  problems

  • Significant improvement at 6 mo (p<.005), with a loss of improvement from 6 to 24 mo (p<.003)

Adherence to treatment

  • No differences between groups

Relationships among variables

  • Weight change related only to change in problem solving (r=.32, p<.05)
  • Problem-solving change related only to change in parent distress (r=.42, p<.025)
Author Conclusion:

The standard group [Gp 3] showed larger BMI decreases than the parent + child group [Gp 1] through 2 years, with significant differences in the percentage of children who showed large BMI changes. Significant statistical and clinical improvements were observed over time in child behavior problems and parental distress.  Parent problem solving increased in the parent + child condition relative to the other conditions, whereas child problem solving increased equally in all conditions. 

The bulk of evidence suggests that problem solving did not add to treatment effectiveness beyond the standard family-based treatment.

Combined parent and child training in problem solving may compromise the standard treatment [for children]. 

Problem solving did not add to weight control for parents. Changes in parent problem-solving were related to improvements in general parental distress and in parent, but not child, obesity.

Funding Source:
Industry:
Johnson & Johnson Medical, Nellcor/Puritan-Bennett
Pharmaceutical/Dietary Supplement Company:
Other:
University/Hospital: Frances Payne Bolton School of Nursing, Case Western Reserve University
Not-for-profit
0
Foundation associated with industry:
Reviewer Comments:

Strengths:

  • Thorough description of study protocol & subject characteristics,
  • subjects stratified into groups on basis of several potential confounders,
  • intention to treat analysis.

Limitations: 

  • Unclear sample size (62 or 52?),
  • no blinding of measurements,
  • not clear if problem solving training impacted problem solving ability as measure of such did not appear to differ by group or if problem solving is effectively (but not intentionally) learned in standard treatment protocol.
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? ???
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) ???
  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? ???
  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.) ???
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? ???
4. Was method of handling withdrawals described? No
  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? ???
  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? ???
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? ???
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? ???
  5.5. In diagnostic study, were test results blinded to patient history and other test results? ???
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? ???
  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? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? ???
  6.6. Were extra or unplanned treatments described? ???
  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? ???
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? ???
  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? 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)? Yes
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? Yes
  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? ???
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