PWM: Eating Behaviors of Children (2006)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To analyze the differences between the breakfast habits of obese/overweight (O) and normal weight (N) schoolchildren
Inclusion Criteria:

For schools:

  • low-middle SES,
  • school canteen with sufficient use,
  • sufficient school size
Exclusion Criteria:

For students:

  • disease or disorder (e.g. hypercholesterolemia, hypertriclyceridemia, diabetes, renal disease)
  • use of medications (e.g., glucocorticoids, diruretics, steroids)
  • absence at time of study
  • lack of consistency in answers given (resulted in n of 200 or 60% of those originally selected)
Description of Study Protocol:

Recruitment – 2 schools in Madrid, Spain selected by random from a group of eligible schools; 8 class groups chosen at random from each school; 334 children who ate at canteen invited; of those 210 (63%) agreed

Design – Questionnaires completed by students & parents (not clear how much done at school vs. at home)

Statistical Analysis – ANOCOVA, separate analyses by gender, adjusting for degree of under- or overestimation of intake
Data Collection Summary:

(no blinding)

Independent variables

  • (7-day consecutive food record by parents and subjects, weighed or measured with household cups/spoons; weighed food intake by study personnel for school lunch)
  • Breakfast

Dependent variables

  • BMI (measured) classification:  Not OW (<75th%, OW/OB (>75th%)  (using criteria of Hernandez, 1993 and Must, 1992)

Other variables

  • Physical activity (questionnaire)
  • SES (parent’s occupation & characteristics of home?)

Control variables

  • Gender
  • Degree of under- or overestimation of intake (based on reported intake vs. estimation of energy requirement given reported PA using WHO equations)
Description of Actual Data Sample:

N: 200 (118 boys, 82 girls)

Age: Mean 11 y (9-13 y)

Ethnicity: not described

Other demographics: middle or low SES

Summary of Results:

Breakfast eating

  • Skipping breakfast(all 7 days) higher in overweight (3.3% & 8.7% in males and females, respectively) than normal (2.3% and 1.7% in males and females, respectively), especially in girls (p < .05)
  • Breakfast size (in terms of kcals and many other nutrients) smaller in overweight (18.6% and 16.3% of total kcals in males and females, respectively) than normal (19.4% and 18.3% in males and females, respectively) (p<.05)

Other Results

  • overweight children underestimated intake more than normal weight children
Author Conclusion:

Without doubt, overweight subjects have less satisfactory breakfast habits than normal weight subjects. This might be a reflection of a whole diet that is less adequate. However, it is possible that an inadequate breakfast contributes to the making of poor food choices over the rest of the day, and, in the long tern, to an increased risk of obesity.

Funding Source:
Industry:
Danone S A
Food Company:
University/Hospital: Universidad Complutense,
Reviewer Comments:

Strengths: Extensive dietary data collection, random selection of eligible schools & classrooms, control for under/overreporting

Weaknesses: Did not control for SES, PA or other diet measures in eating breakfast analysis; ‘generous’ definition of overweight/obese?

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? 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%.) N/A
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? N/A
  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.) 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? 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? 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? 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? No
9. Are conclusions supported by results with biases and limitations taken into consideration? No
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? No
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? No