PWM: Family Influences (2006)
Citation:
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
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
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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 | |