Pediatric Weight Management

Pediatrics and Physical Activity

Citation:

Arluk SL, Branch JD, Swain DP, Dowling EA. Childhood obesity’s relationship to time spent in sedentary behavior. Military Medicine 2003; 168: 583-586.

 
Study Design:
Cross-Sectional Study
Class:
D - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:
To examine the relationship between sedentary behaviors and childhood obesity in US Navy dependents.
Inclusion Criteria:

Subjects who completed all three questionnaires and had no documented endocrine or metabolic disorder that could precipitate obesity.

Exclusion Criteria:

Not specified.

Description of Study Protocol:

Everyday for one month, parents of children attending the Pediatric or Nutrition Clinic at the Naval Medical Center Portsmouth or Boone Clinic in Virginia Beach were handed a survey package upon check-in.

Data Collection Summary:

Dependent Variables: 

Obesity: Self-reported heights and weights; BMI >95th percentile as determined by new pediatric growth charts (Kuczmarski et al, CDC growth charts, US, Advanced Data 2000).

Independent Variables: 

  • Factors related to time spent in vigorous and moderate level activity as well as time spent in sedentary activity (Questionnaire)
  • Dietary intake (Modified 24-hour recall)
  • Parent obesity (At least 30kg per m2, based on self-reported height and weight)

A parent survey was used to verify children’s results on dietary intake and exercise as well as obtain familial adiposity patterns.

Control Variables: 

None reported.

Statistical Analysis: 

  • Chi-squared compared obesity status in children with various independent variables
  • Logistic regression to determine key variables in predicting childhood obesity
  • k-analysis of reliability for child compared to parent responses.
Description of Actual Data Sample:
  • Initial N: Convenience sample of 101 children from Navy families – children of US Navy personnel.
  • Withdrawals/Drop-outs: Not specified
  • Attrition (final N): Complete data was available on 98 children, 88 mothers and 81 fathers
  • Age: 9 to 12 years 
  • Ethnicity:
    • 31% African American 
    • 52% non-Hispanic White
    • 5% Hispanic
    • 5% Asian
    • 3% Other
  • Location: Hampton Roads, Virginia area
  • SES: Military-dependent population.

 

Summary of Results:

Total Caloric Intake:

  • Total caloric intake showed no significant relationship with obesity in this population
  • This may be explained by the fact that throughout the research completed on this subject, underreporting of caloric intake by children has been consistently noted, especially among obese children
  • Underreporting of nutrient intake in this study was observed in both obese and non-obese children and parent records correlated among most food groups with their children’s answers at a high significance level.

 Logistic Regression:

  • The strongest independent predictor of childhood obesity was if the child’s mother was also obese (sensitivity of 71%)
  • If the child participated in a large number of hours of sedentary activity daily, there was a strong association with obesity: 
    • Hours on the computer during the week (x2= 13.68, P=0.01)
    • Hours watching television during the week  (x2=14.58, P=0.01)
    • Frequency of child exercising with Dad (x2=12.02, P=0.04)
    • Presence of parent when child gets home from school (x2=6.62, P=0.01).
Author Conclusion:
  • Childhood obesity is a multifactorial issue with a strong correlation with the obesity status of the maternal household member and time that the child spends in inactive behavior patterns
  • Interventions should be designed targeting total time spent on the computer, total time watching television and maternal obesity in child obesity programs
  • This study lends credence to the fact that 9 to 12-year-old children can accurately depict their lifestyle patterns both from a dietary and activity standpoint and that parents of this age group realistically see their children’s current activity level and obesity status.
Funding Source:
University/Hospital: Old Dominion University,
Reviewer Comments:

Limitations:

  • Small sample size
  • Self-reported heights and weights
  • Sampling effect because it surveyed only those children who presented at the pediatrician’s office
  • Population of military dependents showed higher than anticipated levels of obesity.
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) 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? No
  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? No
  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? 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.) No
  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? Yes
  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")? Yes
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? 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? 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.) No
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? No
  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? 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? N/A
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? N/A
  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? 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? N/A
  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? ???
  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? 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? ???
  10.2. Was the study free from apparent conflict of interest? Yes