Pediatric Weight Management

PWM: Family Influences (2006)

Citation:

Davison KK, Birch LL. Processes linking weight status and self-concept among girls from ages 5 to 7 years. Developmental Psychology. 2002; 38: 735-748.

PubMed ID: 12220051
 
Study Design:
Panel design study.
Class:
C - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

To assess factors that mediate the relationship between girls’ weight status and self-concept at ages five and seven years.

Inclusion Criteria:

Five-year-old white girls living with both biological parents in central Pennsylvania.

Exclusion Criteria:
  • Girls with severe food allergies or chronic medical problems that affect food intake
  • Dietary restrictions involving animal products.
Description of Study Protocol:

Each girl was individually interviewed by a trained interviewer on two separate occasion (at age five years and age seven years). Weight and height were measured at the time of each interview. At each interview time, parents completed four questionnaires that asked about their spouses' attitudes about and criticism of their daughters' weight status. Mothers were asked to report on family income and parent educational levels at each interview time. At the first interview time, both parents completed a questionnaire regarding tier beliefs about parental control of children. 

Statistics

  • Pearson product-moment correlations were used to assess associations between girls' BMI and self concept at each age
  • Multiple regression analysis was used to assess the relationship between BMI and each domain of self concept
  • Differences in girls' BMI as a function of their history of teasing and parent criticism were assessed using analysis of variance (ANOVA)
  • Differences in girls' self-concept at age seven for each of the teasing and criticism groups was assessed using multivariate analysis of variance (MANOVA); where a multivariate effect was identified, a Roy-Barmann stepdown analysis was performed to determine which domains of self-concept differed as a function of teasing and criticism across ages five to seven
  • The association between teasing and criticism and body esteem  was assessed first using a one-way ANOVA. The  association between teasing and criticism and each of the remaining domains of self concept was assessed in a series of analyses of covariance (ANCOVAs)
  • A combination of logistic regression and multiple regression analysis was used for the cross-sectional analyses.

 

Data Collection Summary:

Dependent

  • Girls’ self-concept, including perceived physical appearance
  • Peer acceptance
  • Physical ability and cognitive ability (Pictorial Scale of Perceived Competence and Social Acceptance for Young Children, Body Esteem Scale, Peabody Picture Vocabulary Test). 

Independent

  • Girls’ weight status: BMI percentiles (overweight, BMI more than 17.2 at age five years and BMI more than 18.0 at age seven; obese, BMI more than 19.3 at age five and BMI more than 21.0 at age seven)
  • Peer weight-related teasing (teasing checklist)
  • Parental weight-related criticism (mothers provided reports of paternal criticism and fathers provided reports of maternal criticism)
  • Parental control (General Parental Control scale).

Control Variables

  • Family income
  • Parental educational status
  • Parental control.
Description of Actual Data Sample:
  • Sample: 182 girls
  • Age: Five years old
  • Ethnicity: White
  • SES: Well-educated, middle-income families
  • Location: Central Pennsylvania.
Summary of Results:

Cross-sectional Results

The odds (OR=1.8, 1.4 to 2.5) of Parent Criticize increased with BMI at age five and the odds (OR=1.9, 1.5 to 2.5) of Parent Criticize increased with BMI at age seven. (i.e., girls with a higher BMI had a greater likelihood of being criticized by their parents about their weight). 

Longitudinal

At age seven, parent criticism and peer teasing mediated relationships previously identified between girls’ BMI and self-concept.

Author Conclusion:

Peer-teasing and parent criticism generally served as concurrent rather than long-term mediators of the relationship between weight status and self-concept among young girls and that mediation was not apparent until age seven.

Funding Source:
University/Hospital: Pennsylvania State University
Reviewer Comments:

Primary results of this study did not focus on our hypothesis but the descriptive data lent itself well to studying our hypothesis.

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%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? No
  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.) Yes
  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? Yes
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? 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)? No
  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