PWM: Prescribed Diet Plan and Nutrition Education (2006)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

The present study introduces a weight reduction program developed to include diet, exercise, behavior modification & parental involvement for obese children and adolescents in Taiwan. The efficacy of this comprehensive, outpatient-based program during treatment and after one-year follow-up was evaluated.

Inclusion Criteria:

Subjects were consecutive participants in the Pediatric Nutrition Counseling Clinic at Taipei Municipal Chung-Hsiao Hospital between January 1992 and December 1993. Age of 18 years or less, with a primary diagnosis of obesity (defined as weight-for-length index (WLI) greater than 1.2) (Chen, et al. 1993, Weight for length index in evaluation of children’s body weight status: a simple and accurate method), good health, not involved in other formal weight loss programs & were able to attend the clinic with their parents were criteria for inclusion.

Exclusion Criteria:

Not specified.

Description of Study Protocol:

Wright Reduction Program: Individualized six-session program that included parent involvement, diet education, exercise management & behavior modification by a culturally sensitive method.

The weight reduction program included three weekly and three biweekly sessions (6 treatment modules included the importance of parental & family involvement, the five-lamp diet, the 25% deficit diet, lifestyle exercise, behavioral modification and a summary session). Based on the conceptual model of the traffic-light diet (Epstein, 1985) and balanced deficit diet (Dietz, 1983), the five-lamp diet and 25% deficit diet were adapted to the needs and interests of children in Taiwan. The five-lamp diet was designed for the participants to understand the energy density of common foods. This diet divided food into five categories. Foods were separated into five color groups: red, orange, yellow, green and blue. Red foods are those that contain the highest calories per fixed weight or volume. Various daily activities, including walking and using stairs, focused on lifestyle exercise.

Statistical Analysis

  • Statistical analyses were performed separately on data of those participants who completed five or more sessions of the program and who attended follow-up.
  • Paired t-test was used to assess the statistical significance of change in weight, height & other parameters. Linear regression methods were used to analyze the influence of age, initial WLI and end-of-treatment WLI changes on WLI changes at follow-up.
Data Collection Summary:

Dependent

  • Changes in the degree of obesity (weight for length index (WLI)).

Independent

  • Pretreatment measurements,
  • End-of-treatment measurements
  • Follow-up Measurements.

Control Variables

  • Gender
Description of Actual Data Sample:

Original Sample: 68 obese children and adolescents (39 boys, 29 girls) enrolled.

Withdrawals/Drop-Outs: the initial WLI, end-of-treatment WLI changes and the gender or age of the 12 children who did not participate in follow-up (7 boys & 5 girls) were not significantly different from those of the participants/final sample.

Final Sample: 56 patients were followed up 1 year after treatment (82% of original sample).

Location: Taiwan

Race/Ethnicity: Chinese children & adolescents.

SES: not specified

Age: mean age 10.1 (range 5-18 y)

Summary of Results:

Changes in degree of obesity (WLI)

The mean baseline WLI declined significantly (p<0.0001), indicating a decrease in relative weight. The mean WLI at follow-up examination in these participants was 1.7 which was significantly lower than the value 1.9 with which they began the program.

97% of participants were below their pretreatment WLI at the end of treatment examination & 80% at 1-year-after treatment follow-up. At 1-year-after-treatment, 59% showed a reduction in WLI of 0.1 or more, as compared with 38% of participants at end-of-treatment.

Boys & girls in the program did not differ significantly in their change in the WLI.

Growth

Participants exceeded their pretreatment weight by an average of 5.5 kg. Part of this weight gain was anticipated from increased height, which increased in 56 participants from 144.3 cm at baseline to 151.8 cm at the one-year follow-up.

Correlations

The correlation between the initial WLI & WLI reduction were significant at the end of treatment (r=0.44, p<0.0005), but were weak and not significant at the 1-year follow-up. The WLI change at the end of the treatment correlated significantly with WLI reduction at 1-year follow-up (r=0.58, p<0.0005).

Regression model

Two parameters previously considered predictors of successful weight control, notably age of the participants and % of weight loss during the treatment, were significantly associated with a reduction in the degree of obesity after one year.

Author Conclusion:

Although the long-term efficacy cannot be determined, these results indicated that this comprehensive weight reduction program may have an encouraging effect on the weight status of obese Chinese children and adolescents.

Funding Source:
University/Hospital: Taipei Municipal Chung-Hsiao Hospital
Reviewer Comments:

Strengths

  • Multidisciplinary approach.
  • Normal development growth was not effected by program/intervention.
  • Participants at follow-up did not different from the 12 participants who were not included in follow-up.

Limitations

  • No controls
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) N/A
  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) N/A
 
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? N/A
  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? N/A
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) N/A
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? N/A
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) N/A
  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? N/A
  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? N/A
  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? 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? Yes
  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? Yes
  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? No
  7.7. Were the measurements conducted consistently across groups? N/A
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? 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