EAL

PWM: Prescribed Diet Plan and Nutrition Education (2006)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To test a new parent-focused approach for modifying eating behavior in at-risk children and their parents.

Inclusion Criteria:

Families with at least one obese parent and a six- to 11-year-old non-obese child.
Overweight (parents): BMI greater than the 85th percentile
Non-obese (children): BMI below the 85th percentile.

Exclusion Criteria:

A child with a BMI greater than the 85th percentile.
Family members on an alternative weight control program, with current psychiatric problems or with dietary or activity restrictions for the participating parent or child.

Description of Study Protocol:

Recruitment

Physician referrals, posters, newspapers and television advertisements for the Childhood Weight Control and Prevention Programs at the University of New York at Buffalo.

Design

Parents were instructed to modify their behavior and the familial environment to reduce their obesity and were taught parenting skills for promoting and reinforcing behavior change in the at-risk children.
The dietary changes suggested for the parents would result in a second goal of reducing weight in parents of at-risk children.
Families with at least one obese parent and a normal weight child were randomized to groups that targeted either:
- A decrease in consumption of high-fat, high-sugar foods or
- An increase in consumption of fruits and vegetables
Families were followed for one year. The targeted behavior was a change in eating habits for parents and children leading to a decrease in weight for parents and to stabilization of relative weight for children.

Diet Intervention

Diet was restricted to between 1,200-1,500 calories per day. When participants got below the obesity criterion (<85th percentile), they were instructed on how to develop a maintenance calorie level, which involved gradually increasing caloric intake in 100-kcal/d increments until weight gain occurred.

Treatment Format

The treatment meetings were in group format (30 minutes), but participating parents also met with an individual therapist for 30 minutes. Participating children and parents attended the first meeting together and were seen together at follow-up, at six and 12 months. Other group meetings were attended by parents only (eight weekly meetings, followed by four bi-weekly meetings and two monthly meetings during the six-month intensive treatment).

Statistical Analysis

T-tests (between-group differences), mixed analysis of variance (changes in dependent variables established separately for parents and children with the between-subject factors of group and a repeated measures within-subjects factor), Pearson correlation coefficients (predictors of change in child and parent intake and percentage of overweight).

Data Collection Summary:

Timing of Measurements

Weight-control treatment was provided to the parents for eight weekly meetings, followed by four bi-weekly and two monthly meetings during the six-months of intensive treatment.

Dependent Variables

Body mass index.

Independent Variables

Family history of obesity and related diseases
Food intake (food habits and food intake questionnaires)
Psychological measures (child feeding questionnaire)
Socioeconomic status
Treatment of groups (increase fruit and vegetable intake, decrease fat and sugar intake).

Control Variables

Age
Gender.

Description of Actual Data Sample:

Initial N

30 families.

Attrition (final N)

27 families.

Age

Six to 11 years.

Gender of Parents: 2 males, 23 females (missing data for 4); no childrens' gender indicated

Location: Buffalo, NY

SES: Assessed (using Hollingshead’s Four-Factor Index of Social Status) but was never provided in detail in baseline data or in results & discussion sections. No difference in SES are known.

Summary of Results:

The average participating parent was 65.7% overweight. Every family had at least one parent or grandparent with an obesity-related risk factor. The parents were quite confident that they could lose weight (4.1±0.9), but less confident that they could make eating (2.1±1.0) or activity (2.1±1.1) changes. The parents were less confident that they could help their children change their eating (1.8±0.9) or their activity (1.7±1.3) habits.

There were no differences in the number of sessions attended by each group.

Parents showed significant differences in fruit and vegetable intake over time by group (P<0.025). High-fat/high-sugar intake showed a significant decrease across groups over time (P<0.001). Children also showed significant between-group differences in fruit and vegetable intake over time (P=0.025) and significant changes in high-fat/high-sugar food intake for both groups over time (P<0.001).

Neither total fat (g) nor percentage of total energy were examined (or controlled for). Only servings per day of high fat/sugar foods were examined. Change from baseline (as opposed to between groups) was examined at 12 months. Significant decreases over time were observed for the Food Habits Questionnaire, with an average decrease of 0.6 for use of fat as seasoning (P<0.001) and an average decrease of 0.31 for substituting low-fat versions of high-fat foods (P<0.025), with the use of fruits increased by 0.47 (P<0.05).

Parents showed significant differences in percentage of overweight change by group (P<0.05), while children showed a stable percentage of overweight over time.

	Group		Significance Levels
	Increase Fruit and Vegetable	Decrease Fat and Sugar	Time	Group x Time
Parent percentage of overweight	-12.01±11.05	-3.94±4.17	<0.001	0.026
Child percentage of overweight	-1.10±5.29	-2.40±5.39	NS	NS

Baseline parent high-fat/high-sugar intake was related to high-fat/high-sugar changes (R=-0.82, P<0.001) and baseline parent fruit and vegetable intake was related to fruit and vegetable changes (R=-0.45, P<0.025). Baseline child high-fat/high-sugar intake was related to high-fat/high-sugar changes (R=-0.82, P<0.001). Baseline parent and child fruit and vegetable intake was related to fruit and vegetable changes (R=0.38, P<0.05). Parent changes in fruit and vegetable intake over the year were related to changes in habits of eating fruit (R=0.50, P<0.001).

Percentage of overweight change was greater for parents who targeted increases in fruit and vegetable intake (-12.01±11.05) than reductions in high-fat/high-sugar intake (-3.94±4.17) (P<0.001).

Author Conclusion:

Changes over one year showed that treatment influenced targeted parent and child fruit and vegetable intake and high-fat/high-sugar intake, with the Increase Fruit and Vegetable group also decreasing their consumption of high-fat/high-sugar foods. Parents in the Increased Fruit and Vegetable group showed significantly greater decreases in percentage of overweight than parents in the decreased high-fat/high-sugar group. These results suggest that focusing on increasing intake of healthy foods may be a useful approach for nutritional change in obese parents and their children.

Funding Source:

Government:

NIH

Reviewer Comments:

Limitations

Small sample size.
The sample included families with obesity and related cardiovascular risk factors in parents and grandparents and parents who were concerned enough about preventing obesity in their offspring to enter a behavioral-change program. Parents who are obese, but have not yet experienced obesity-related disease in family members, may be less motivated to participate in an obesity prevention program and motivation for behavior change may be very different in families in which the targeted child is obese and needs to lose weight, compared with families in which the targeted child is non-obese.
The intervention only targets one family member and may not benefit from interactions between family members that support behavior change or changes in the shared family environment that may enhance the treatment effects of the parent.

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?		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.)	Yes
	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?	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%.)	Yes
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	Yes
	4.4.	Were reasons for withdrawals similar across groups?	Yes
	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?		???
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	???
	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.)	???
	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?	Yes
	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?	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?	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)?	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?	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