Pediatric Weight Management

Pediatrics and Physical Activity


Toyran M, Ozmert E, Yardakok K. Television viewing and its effect on physical health of school age children. The Turkish Journal of Pediatrics 2002; 44: 194-203.

PubMed ID: 12405429
Study Design:
Cross-Sectional Study
D - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

The aim of this study was to examine the effect of television viewing on obesity and some other physical health parameters among school age children.

Inclusion Criteria:

Not specified

Exclusion Criteria:

Not specified

Description of Study Protocol:

Students were visited at their schools and their height, weight and triceps skin fold thickness were measured.


Then a questionnaire was sent to the parents of the student to gather information on the parents’ height and weight and the child’s and their parents’ television viewing habits as well as the time the children spent watching TV versus other daily activities. Children who watched less than 2 hours of TV per day (group 1), more than 2 but less than 4 hours per day (group 2 ) and more than 4 hours of television viewing per day (group 3).

The questionnaire also addressed the # of vigorous exercises the child performed per week (3+ were considered active, less than 3 considered “not active enough”)

Statistical Analyses:

The data was analyzed using the student’s t-test and one-way ANOVA tests. Correlations were tested by the Pearson test.

Data Collection Summary:

Dependent Variables

  • Obesity (BMI > 95th percentile and triceps skin fold > 85th percentile)

Independent Variables

  • Television viewing (less than 2 hours of TV per day (group 1), more than 2 but less than 4 hours per day (group 2 ) and more than 4 hours of television viewing per day (group 3).
  • Physical activity (3+ hours per week were considered active, less than 3 considered “not active enough”)


  • SES/Income (low and high groups within the sample)
  • Age (~8 years old)
  • Gender
Description of Actual Data Sample:

886 2nd and 3rd grade students, 472 from low income and 414 from high income primary schools in Turkey.

Summary of Results:

Obesity was higher among boys than girls and higher for upper SES children.


Mean television viewing time of obese and non-obese children was not different.  Obesity was also not different when participants were stratified by TV viewing time.

Among girls, mean daily television viewing time of children was found to be longer for obese girls (p = .021).

Mean number of physical activities was found to have a weak positive correlation with obesity (BMI, r = .119, p = .002;  skin fold, r = .122, p = .001; and for both r =.137, p < .0001)

Author Conclusion:

There was no relation between obesity and television viewing for the whole study group, but mean daily television viewing times of obese girls were found to be longer than for their non-obese peers.


Being “active” was found to be more, among the obese children (using both criteria for obesity)

Overall conclusion:

For female children, TV viewing was found to be associated with obesity.

Being more active was weakly, positively correlated with obesity

Funding Source:
University/Hospital: Gaziosmanpasa University, Haccettepe University
Reviewer Comments:


  • Oneway ANOVA was inappropriate design considering that the multiple factors should have been incorporated together.
  • Results could have been confounded by failure to adjust for social status.
  • Classification of TV viewing and PA into a categorical variable reduces power in the present design and may have limited the outcome.
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? N/A
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? N/A
  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? No
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) No
  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.) 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? No
  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%.) Yes
  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? N/A
  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? 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? N/A
  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? No
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  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? No
  8.1. Were statistical analyses adequately described and the results reported appropriately? No
  8.2. Were correct statistical tests used and assumptions of test not violated? N/A
  8.3. Were statistics reported with levels of significance and/or confidence intervals? N/A
  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)? No
  8.6. Was clinical significance as well as statistical significance reported? N/A
  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? No
  9.1. Is there a discussion of findings? N/A
  9.2. Are biases and study limitations identified and discussed? N/A
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? N/A
  10.2. Was the study free from apparent conflict of interest? N/A