Pediatric Weight Management

PWM: Family Influences (2006)

Citation:

Cutting TM, Fisher JO, Grimm-Thomas K, Birch LL. Like mother, like daughter: Familial patterns of overweight are mediated by mothers’ dietary disinhibition. Am J Clin Nutr 1999; 69: 608-613.

PubMed ID: 10197561
 
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:
To determine whether parent-child similarities in overweight are mediated by parents’ dietary restraint and disinhibition.
Inclusion Criteria:

Children and parents with no chronic medical issues or food allergies.

Exclusion Criteria:

Children and parents with chronic medical issues or food allergies.

Description of Study Protocol:

Subject Recruitment

  • Families were recruited from the Pennsylvania State University’s Child Development Laboratory and a local daycare center. Only one child per family was allowed to participate.
  • Families were paid $20 for their participation.

Measurements Taken

  • Parents: height and weight were measured, body mass index (BMI) was assessed and Eating Inventory Questionnaires were completed (to assess dietary restraint and dietary disinhibition)
  • Children: YHeight and weight were measured and took a hunger assessment following a standard lunch (children who were still hungry were taken to a 10-minute free access session of food following lunch on another day).

Statistical Analysis

  • Correlation analysis was used to determine relations between variables measured in participants
  • Fisher’s R-to-Z transformations was used to assess differences between daughters' and sons' correlations
  • Multiple regression analysis was used to explore mediator models (sample size too size for more complex models)
  • Significance was set at P<0.05.
Data Collection Summary:
  • Dependent variables: Child weight-for-height (measured)
  • Independent variables: Parent’s BMI (measured height and weight); Parents’ restraint and disinhibition (subscale of the Eating Inventory questionnaire)
  • Control variables: Child’s gender.
Description of Actual Data Sample:
  • N: 75 (40 boys and 35 girls) and their parents
  • Age: Median age was 59.4 months in children (age ranged from three to six years) and 37.7 and 39.4 years for mothers and fathers, respectively
  • Ethnicity: Predominantly white
  • SES:
    • Parents were relatively highly educated
    • Mean education levels of the mothers and fathers were 16.6± 2.9 years and 17.2±2.5 years, respectively
  • Other: Predominantly intact families
  • Location: Pennsylvania, US.
Summary of Results:
  • All significant relations were between variables in mothers and daughters only
  • Maternal disinhibition was positively related to daughter’s overweight (R2=0.35; P<0.0040)
  • Mothers’ BMI and dietary disinhibition were significant independent predictors of daughters' weight-for-height
  • Maternal disinhibition mediates the relationship between mothers’ and daughters’ adiposity and accounted for 35% of the variance in daughters' overweight
  • Both mothers’ disinhibition and daughters’ free access intakes were significant independent predictors of daughters’ overweight and together accounted for nearly half of the variance in daughters’ weight-for-height (R2=0.49)
  • Maternal dietary restraint was not significantly related to mothers’ or daughters’ adiposity or to mothers’ disinhibition or daughters’ free access intakes.
Author Conclusion:
  • The authors cite that mothers influence daughters' eating habits and weight outcomes
  • Maternal disinhibition was significantly associated with daughters' free access intake
  • Disinhibition in mothers and free access intake in daughters predicted daughters' overweight
  • No such relations were observed for mothers and sons or for fathers and daughters
  • No relations between dietary restraint and daughters' eating or weight outcomes were observed.
Funding Source:
Government: NIH
University/Hospital: The Pennsylvania State University
Reviewer Comments:

Weaknesses

  • Small sample size prevented the testing of more complex models
  • Final analysis only included 21 girls and 22 mothers.

 

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? N/A
  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? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) Yes
  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.) Yes
  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? 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%.) 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? 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? 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? No
  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? No
  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? No
  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? N/A
  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? Yes
  10.2. Was the study free from apparent conflict of interest? Yes