Pediatric Weight Management

PWM: Foods and Nutrients (2006)

Citation:

Bao W, Nicklas TA, Srinivasan SR, Berenson GS. Body composition and energy and nutritional intake in children. Journal of Advancement in Medicine 1996; 9: 101-112.

 
Study Design:
Cross-Sectional Study
Class:
D - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
  • To examine the association between dietary intake patterns and weight or body composition in a pediatric population
  • To accomplish this, one 24-hour dietary recall was collected on each child who participated in one of six cross-sectional surveys.
Inclusion Criteria:
  • 10-year old children in Bogalusa, Louisiana
  • Bi-racial (Caucasian and African-American).

 

 

Exclusion Criteria:

Not specified.

Description of Study Protocol:

Six cross-sectional surveys were conducted from 1973 to 1988. Within each cross-sectional survey, dietary intake information and anthropometric measurements were collected. 

Study Protocol included:

Dietary

  • One 24-hour recall was collected from each child
  • All interviewers participated in rigorous training sessions and pilot studies prior to data collection to minimize interviewer effects
  • Quality controls included a standardized protocol, graduated food models for estimation of portion sizes, a product identification notebook for snack probing, school lunch and family recipe collection and the Moore Extended Nutrients (MENu), a database for nutrient composition
  • Duplicate recalls were collected from 10% random sub-samples to assess inter-interviewer variability.

Anthropometric

  • Height and weight were measured twice using standardized protocol
  • Triceps and subscapular skinfolds were measured three times using standardized protocol.

 

Data Collection Summary:

Dependent Variables

  • Ponderal index (measured weight and height)
  • Estimated body composition--FFM (weight - body fat), Body Fat (weight X %body fat)
  • Triceps and subscapular skinfolds.

Independent Variables

  • Total energy intake
  • % kcal from protein, fat, carbohydrates or saturated fat (24-hour recalls).

Control Variables

  • Race 
  • Gender.

Statistical Analysis

  • Spearman correlation and multivariate stepwise regression
  • P<0.05 was established as statistically significant.

 

Description of Actual Data Sample:
  • Original sample: Not specified 
  • Withdrawals/Drop-outs: Not specified
  • Final Sample: 1,419 Black and White children; 50% female
  • Age: 10 years of age
  • Location: Bogalusa, Louisiana (semi-rural southern community)
  • Race/Ethnicity: 35% Black and 65% White population
  • SES: Not specified.
Summary of Results:

Total Energy

  • Associations between energy intake and anthropometric measurements were weak.
  • Energy intake was more associated with fat free mass (FFM) (r=0.13, P<0.0005) than with weight (r=0.07, P<0.006) and height (r=0.07, P<0.01) and NOT with skinfolds or body fat
  • The only significant but weak correlation found was between FFM and percent of energy from protein (r=0.06, p=0.04), but not after controlling for energy intake.

 

Percent of Kcals from Macronutrients

No significant correlations were noted between % kcal from fat, saturated fat or carbohydrates and anthropometric measures.

Author Conclusion:
  • Observations from the current study suggest that at least in growing children dietary intake has significant influence on FFM, and may be more significant than its influence on body fat
  • Therefore, other measures, perhaps exercise and behavior are needed to complement dietary management in approaches to prevent obesity in childhood.
Funding Source:
Government: NHLBI
Reviewer Comments:

Strengths:  

  • Dietary methodology--quality controls to mimimize interviewer effects and duplicate recalls to assess inter-interviewer variability
  • Large sample size.

Limitations:

  • Article did specify details of how the 24-hr recalls were collected.
  • Fat-free mass (FFM) calculated in this study as an estimate of body composition utilized sex, but not race-specific equations. Subcucaneous and skeletal fat distribution differs between Blacks and Whites. Race-sex-specific equations may be more accurate in estimating FFM.
  • One 24-hour dietary recall
  • Lack of physical activity data
  • Population was 10-year old children from a single city; generalizability?
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? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? ???
  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) N/A
  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.) 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? No
  4.1. Were follow-up methods described and the same for all groups? ???
  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? ???
  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? No
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? N/A
  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.) N/A
  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? N/A
  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? No
  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? 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)? N/A
  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? 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