Pediatric Weight Management

PWM: Family Influences (2006)

Citation:

Fisher JO, Birch LL. Restricting access to foods and children’s eating. Appetite 1999; 32: 405-419.

PubMed ID: 10336797
 
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:
  • Primary objective: To evaluate the relationship between mothers’ restriction of children’s access to foods and children’s eating
  • Secondary objective: To determine whether mothers’ reports of restricting their children’s access to snack foods could be predicted by weight and eating “risk” factors of the parent or child.
Inclusion Criteria:
Children attending day-care programs at The Pennsylvania State University and their parents.
Exclusion Criteria:

Children with food allergies, lactose intolerance or unwillingness to participate.

Description of Study Protocol:
  • Children were seen individually in a setting where they were provided free access to toys and to generous quantities of the 10 snack foods
  • To minimize the influence of hunger on snack food intake children were seen immediately after eating their usual lunch (relevant for the primary objective only)
  • Parents completed a set of questionnaires at home.
Data Collection Summary:
  • Dependent variables: Mothers’ reports of restricting their children’s access to snack foods (series of questions)
  • Independent variables: 
    • Child’s weight: Measured weight and height, percentile scores using age- and gender-appropriate reference data and subscapular and triceps skinfold measures
    • Eating “risk” factors of the parent or child: Child adiposity and parent’s own eating styles and adiposity (Three Factor Eating Questionnaire and mothers’ and fathers’ self-reported height and weight)
  • Variables controlled for: Gender and parental adiposity
  • Statistical analysis: Pearson’s rank-order correlation and multiple regression analyses.
Description of Actual Data Sample:

 

  • Initial N: 70 children (40 boys, 30 girls) and their parents
  • Age: Three to six years old
  • Ethnicity: Mostly white sample with three Black, one Hispanic and six Asian children
  • Other relevant demographics: Parents were all well-educated and employed and were slightly overweight.

 

Summary of Results:

Parental Influences (+)

  • Maternal restriction increased as children’s adiposity (boys and girls) increased, but not as a function of parents’ adiposity
  • Both children’s adiposity (children’s weight-for-height) and the interaction of parental restraint and child gender explained unique variance in maternal restriction, accounting for 27% of the variance in scores.

Other Results

  • For girls only, greater levels of maternal restriction were associated with high energy intakes in an unrestricted setting
  • For boys, this relationship was not statistically significant
  • Parents’ own restrained eating style predicted restriction of girls’ access to snack foods.
Author Conclusion:
Suggests that children’s adiposity may elicit parental concern and consequently a restrictive approach to child feeding.
Funding Source:
University/Hospital: The Pennsylvania State University
Reviewer Comments:
  • Cross-sectional nature of study cannot address issues of causality
  • Small convenience sample
  • This instrument was designed and used for the first time in this study (high-degree of internal consistency).
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) Yes
 
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? No
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")? N/A
4. Was method of handling withdrawals described? N/A
  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? Yes
  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? 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? 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? 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? Yes
  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? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  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)? N/A
  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