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Thompson D, Baranowski T, Cullen K, Watson K, Liu Y, Canada A, Bhatt R, Zakeri I. Food, fun, and fitness internet program for girls: Pilot evaluation of an e-Health youth obesity prevention program examining predictors of obesity. Prev Med. 2008 Nov; 47(5): 494-497. Epub 2008 Jul 30.

PubMed ID: 18718846
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 present behavioral and psychosocial outcomes of an eight-week Internet-based pilot study promoting increased fruit, 100% juice and vegetable consumption and physical activity to young girls. 

Inclusion Criteria:

Eight- to 10-year-old African American girls with a body mass index (BMI) of greater than or equal to 50th percentile, with a home computer, Internet access and an e-mail address.

Exclusion Criteria:

None specifically listed but based on the inclusion criteria listed: 

  • Younger than eight years old or older than 10 years old
  • BMI under 50th percentile
  • No home computer
  • No home Internet access
  • No e-mail address.
Description of Study Protocol:


Included both broadcast and non-broadcast methods.


  • Pilot outcome evaluation is a secondary analysis of a trial assessing the effect of incentive schedule on log-on rates in an Internet-based intervention
  • The main study followed a randomized, two-group design, with baseline and immediate post-assessment. Groups varied on incentive schedule only (immediate, delayed). Reports pre- vs. post-behavioral and psychosocial outcomes. 

Dietary Intake/Dietary Assessment Methodology

  • Fruit, 100% juice and vegetable consumption was assessed using a seven-item food frequency questionnaire (FFQ). The questionnaire was modified for use with young children by asking recall consumption over the last week. French fries were excluded from analysis
  • Total daily consumption was determined by summing servings and diving by seven.

Blinding Used

All data collected occurred on the program Web site.


  • The eight-week Internet intervention emphasized fruit, 100% juice, vegetables, water and physical activity 
  • The treatment Web site from a previous study with African American girls was adapted to a stand-alone Internet program by adding an introduction and a club member manual
  • Social Cognitive Theory guided the content, while Elaboration Likelihood Model guided character development, story line and design framework
  • Participants' weekly goals were to increase fruit, 100% juice, vegetable and water consumption and lifestyle physical activity. Weekly programming included role modeling comics, problem solving and goal-setting and review
  • Participants received a weekly incentive worth $5 for completing all activities. Incentives were awarded on an immediate (within two business days) or delayed (end of program) schedule.  

Statistical Analysis

Repeated measures analysis of variance was used to detect differences in fruit, 100% juice, vegetable, physical activity behavior, and self-efficacy, separately, between incentive groups (immediate, delayed), time (pre-, post-) and group-by-time.

Data Collection Summary:

Timing of Measurements

  • The eight-week study was conducted from September to November, 2004
  • Pre-measurements were collected through self-report via the program Web site prior to the eight-week Internet intervention
  • Post-measurements were collected through self-report via the program Web site taken at the conclusion of the eight-week Internet intervention.

Dependent Variables

  • Physical activity (yesterday): Assessed with the GEMS Activity Questionnaire. Response scales were: 
    • None = zero
    • Less than 15 minutes = one
    • Greater than or equal to 15 minutes = two
  • Physical activity (usually):  Assessed with the GEMS Activity Questionnaire. Answers were weighted by multiplying each activity response with the corresponding child-appropriate MET value. MET-valued responses were summed and subsequently divided by total METS. Response scales were: 
    • None = zero
    • A little = one
    • A lot = two
  • Fruit, juice, vegetable (behavior): Assessed using a modified seven-item FFQ.  Recall consumption was collected over the last week. French fries were excluded. Total daily consumption was determined by summing servings and dividing by seven
  • Physical activity (self-efficacy): Measured using a questionnaire. Response options (no = zero, not sure = one, yes = two) were summed
  • Fruit, juice, vegetable (self-efficacy): Measured with a modified version of a questionnaire. Response options (do not agree = zero, slightly agree = one, strongly agree = two) were summed.

Independent Variables

  • Incentive groups (immediate, delayed)
  • Time (pre-, post-)
  • Group-by-time.
Description of Actual Data Sample:
  • Initial N: 80
  • Attrition (final N): 73
  • Age: 8 to 10 years
  • Ethnicity: African American
  • Other relevant demographics: Girls 
  • Anthropometrics: BMI ≥50th percentile
  • Location: US (Greater Houston, TX).
Summary of Results:


Statistically significant pre- to post-differences were observed in fruit,100% juice and vegetable consumption (P=0.002); physical activity, yesterday (P<0.001); physical activity, usually (P=0.001); and fruit, 100% juice, and vegetable self-efficacy (P=0.003).

Variables Group 1 Group 2 Total  Multivariate Effect Size
  N M (SD) N M (SD) N M (SD) Time Group T*G
Physical Activity (yesterday) Pre- 37 2.74 (1.36) Pre- 36 2.50 (1.36) 73 2.62 (1.36) 0.32 0.03 0.01
  Post- 37 4.38 (2.07)  Post- 36 3.72 (1.51)  73  4.05 (1.83)       
Physical Activity (usually) Pre- 37  3.98 (1.72) Pre- 36 3.06 (1.69)  73  3.74 (1.75)  0.14  0.03  0.00 
  Post- 37 4.85 (2.19)  Post 36   4.17 (1.69)  73 4.51 (1.98)       
Fruit/juice/vegetable (behavior) Pre- 35 2.36 (1.40)  Pre- 36   3.49 (1.78) 71  2.71 (1.54)  0.13  0.02  0.02 
  Post- 35 3.75 (2.70)  Post- 36 3.69 (2.16)  71  3.72 (2.42)       
Physical Activity (self-efficacy) Pre- 36   29.36 (4.58) Pre- 36   28.89 (3.79) 72  29.13 (4.18)  0.01  0.00  0.00 
  Post- 36   28.78 (4.67) Post- 36  28.58 (5.75)  72  28.68 (5.21)       
Fruit/juice/vegetable (self-efficacy) Pre- 35  51.31 (11.96) Pre- 36   48.02 (10.53)  71  49.67 (11.29)  0.12  0.03  0.00 
  Post- 35 56.17 (10.37)  Post- 36  53.36 (14.19)  71  54.77 (12.44)       


Author Conclusion:

Internet-based obesity prevention programs may be an effective channel for promoting healthy diet and physical activity behaviors to youth at-risk of obesity.

Reviewer Comments:
  • Use self-reported measures and note possibility of socially desirable responses
  • Pilot study with small sample size for only eight weeks
  • No control group
  • Required participants to have a computer, Internet access and e-mail, which would likely exclude most at-risk youth from participating
  • Passive, sedentary activity of sitting at computer a focal point of the intervention on promoting physical activity.

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?