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Hopper CA, Munoz KD, Gruber MB, & Nguyen KP. The effects of a family fitness program on the physical activity and nutrition behaviors of third-grade children. Research Quarterly for Exercise and Sport. 2005, 76(2), 130-139. 

PubMed ID: 16128481
Study Design:
Randomized Controlled Trial
A - Click here for explanation of classification scheme.
POSITIVE: See Research Design and Implementation Criteria Checklist below.
Research Purpose:

To determine if a school-based cardiovascular health promotion program with a family participation component would improve specific physical fitness and nutrition behaviors. 

Inclusion Criteria:
  • Agree to participate in all the research intervention components
  • Parental consent
  • Teacher participation in 10 hours of training regarding the health lessons
  • Third grade students in Humboldt County, California.
Exclusion Criteria:
  • Lack of consent to participate
  • Outside the researcher's geographic area
  • Inability to complete the research components.
Description of Study Protocol:


Not provided. Six elementary schools in Humboldt County, California, agreed to participate.


Pre-test and post-test were randomized by schools. 

Dietary Intake/Dietary Assessment Methodology

  • Two-day, 24-hour dietary recall technique
  • An exercise and nutrition knowledge questionnaire composed of 25 questions related to CV health. 


  • Physical education instruction
  • Nutrition education training
  • Home program for parents and children
  • Nutrition activities.

Statistical Analysis

  • Correlations among each of the measure variables were explored
  • The correlations between pre-test and post-test measures in the control group were used to check the test-retest reliability of each variable
  • Pre-test and post-test fitness and dietary means for control group and program group schools were calculated. 
Data Collection Summary:

Timing of Measurements

At baseline (fall term) pre-tests were given on each child in both the treatment and control groups. Post-tests were conducted in late spring (eight months after the pre-testing), and follow-up testing occurred on selected measures one year after the post-testing.

Dependent Variables

  • Height
  • Weight
  • BMI
  • Skinfolds
  • Blood cholesterol
  • One-mile run (measure in seconds)
  • Exercise
  • Nutrition knowledge
  • Kilocalories (kcals)
  • Protein
  • Carbohydrate (CHO)
  • Fiber
  • Total fat
  • Saturated fat
  • Dietary cholesterol
  • Sodium
  • Percentage of kcals from fat
  • Percentage of kcals from CHO

Independent Variables

Intervention treatment program (family fitness program).

Description of Actual Data Sample:
  • Initial N:
    • Six schools randomly assigned to program vs. control groups
    • Nine classrooms in treatment group; six classrooms in control group
  • Attrition (final N):
    • Out of 381 students, a total of 238 students participated in the study
    • 60% in treatment group; 40% in control group
  • Age:
    • Mean age: 102.82 months with a SD of 7.6 months
    • Students were between eight and nine years of age
  • Ethnicity: Caucasian, 83%; Native American, 5%; Asian, 5%; Hispanic, 5%; and African American, 2%
  • Other relevant demographics: 117 girls (49%), 121 boys (51%)
  • Anthropometrics: Measurements included height, weight, triceps and calf measurements
  • Location: Rural area of Humboldt County, California. 
Summary of Results:

Outcome Measures and Tools Used per Group

  • Intervention group received a health-related fitness school-based program and a home program for parents and children
  • Control group received no additional instruction in nutrition and physical education beyond that provided in their regular school curriculum. 


  • Fitness measures:
    • Girls scored higher at pretest on skinfold sums (27.44±1.06) (mean±SD) compared to boys (24.09±11.36). This was significant at the P< 0.05 level.
    • The girls also scored higher on fitness knowledge (12.18±3.13) than the boys (11.35±3.07). This was significant at the P<0.05 level. 
    • Pearson correlations showed significant relationships between age, height and weight. Older children were taller, weighed more and had higher BMI scores at pre-test. 
    • The fitness measures between the program schools and the control schools indicated no difference between the schools at the pre-test measurement or at follow-up. At post-test, the program schools scored significantly higher (15.41±1.1) than the control schools (13.43±0.55) on mean knowledge scores. This was significant at the P<0.05 level. 
  • Dietary intake:
    • Dietary recalls were completed at pre-test and post-test by a randomly selected subset of students
    • Dietary intake of kcals, protein, CHO, fiber, total fat, saturated fat, dietary cholesterol, sodium and percentage of kcals from CHO and fat were analyzed
    • There were no differences among the program school means vs. control schools at pre-testing
    • At post-test, the program schools scored significantly lower (57.05±4.21) compared to the control schools (64.68±0.87) on mean total fat intake. This was significant at the P<0.05 level. 
Author Conclusion:

The program demonstrated that schools can adjust the curriculum to meet some health needs of students and their parents. Some significant changes occurred in increased knowledge and reduction of total dietary fat intake. 

Reviewer Comments:


Research Design and Implementation 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)
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to nutrition or dietetics practice?
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies)
Validity Questions
1. Was the research question clearly stated?
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated?
  1.3. Were the target population and setting specified?
2. Was the selection of study subjects/patients free from bias?
  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?
  2.2. Were criteria applied equally to all study groups?
  2.3. Were health, demographics, and other characteristics of subjects described?
  2.4. Were the subjects/patients a representative sample of the relevant population?
3. Were study groups comparable?
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?
  3.3. Were concurrent controls used? (Concurrent preferred over historical controls.)
  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?
  3.5. If case control or cross-sectional 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. Criterion may not be applicable in some cross-sectional studies.)
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?
4. Was method of handling withdrawals described?
  4.1. Were follow-up methods described and the same for all groups?
  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%.)
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for?
  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?
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?
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status?
  5.5. In diagnostic study, were test results blinded to patient history and other test results?
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were intervening factors described?
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied?
  6.2. In observational study, were interventions, study settings, and clinicians/provider described?
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured?
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described?
  6.6. Were extra or unplanned treatments described?
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?
  6.8. In diagnostic study, were details of test administration and replication sufficient?
7. Were outcomes clearly defined and the measurements valid and reliable?
  7.1. Were primary and secondary endpoints described and relevant to the question?
  7.2. Were nutrition measures appropriate to question and outcomes of concern?
  7.3. Was the period of follow-up long enough for important outcome(s) to occur?
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?
  7.5. Was the measurement of effect at an appropriate level of precision?
  7.6. Were other factors accounted for (measured) that could affect outcomes?
  7.7. Were the measurements conducted consistently across groups?
8. Was the statistical analysis appropriate for the study design and type of outcome indicators?
  8.1. Were statistical analyses adequately described and the results reported appropriately?
  8.2. Were correct statistical tests used and assumptions of test not violated?
  8.3. Were statistics reported with levels of significance and/or confidence intervals?
  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)?
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?
  8.6. Was clinical significance as well as statistical significance reported?
  8.7. If negative findings, was a power calculation reported to address type 2 error?
9. Are conclusions supported by results with biases and limitations taken into consideration?
  9.1. Is there a discussion of findings?
  9.2. Are biases and study limitations identified and discussed?
10. Is bias due to study’s funding or sponsorship unlikely?
  10.1. Were sources of funding and investigators’ affiliations described?
  10.2. Was the study free from apparent conflict of interest?