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Baranowski T, Baranowski J, Thompson D, Buday R, Jago R, Griffith MJ, Islam N, Nguyen N, Watson KB. Video Game Play, Child Diet, and Physical Activity Behavior Change: A Randomized Clinical Trial. Am J Prev Med 2011 Jan; 40 (1): 33-38.

PubMed ID: 21146765
Study Design:
Randomized Controlled Trial
A - Click here for explanation of classification scheme.
POSITIVE: See Research Design and Implementation Criteria Checklist below.
Research Purpose:

Evaluate outcome from playing “Escape from Diab” (Diab) and “Nanoswarm: Invasion from Inner Space” (Nano) video games on children’s diet, physical activity and adiposity.

Inclusion Criteria:
  • Children aged 10-12 years
  • Between the 50th and 95th percentile for body mass index (BMI)
  • Allowed to play video games and having high-speed Internet access (to permit transmission of process evaluation data).
Exclusion Criteria:
  • Not speaking English (since both games were in English)
  • Having a medical condition that influenced diet; physical activity; obesity; or the ability to complete questionnaires
  • Seizure disorder
  • Member of a swim team.
Description of Study Protocol:


Children were recruited with advertisements on a radio station whose listening audience included parents of children in the targeted age groups from ethnic minority communities (African-American, Hispanic).


 Two-arm randomized control design with four assessments of outcome:

  • Baseline
  • Between games (Post 1)
  • Immediate post-game (Post 2)
  • Two months post-game (Post 3).

Children were randomly assigned to intervention (N=103) or control (N=50) groups.

Dietary Intake/Dietary Assessment Methodology

  • Three 24-hour dietary recalls
    • First one in person
    • Subsequent two over the telephone
  • Administered by registered dietitians (RD) trained and certified in Nutrient Data System-Research
  • Regular vegetable intake was defined to exclude high-fat vegetables (e.g., french fries). 

Blinding Used

For anthropometric assessments and 24-hour dietary recalls, data collectors were blinded to group assignment.


Treatment group games

  • Nine sessions
  • Minimum 40 minutes of game-play per session
  • Diab sessions
    • Each had knowledge mini-game designed to provide practical knowledge related to change goals
    • Energy balance was divided into 18 sequential learning activities that built on material in the previous session.
    • Goal setting included:
      • Action and coping (anticipatory problem solving) implementation intentions
      • Behavioral inoculation component involving a motivational message 
      • Goal behavior menu tailored to usual dietary or physical activity behaviors 
  • Nano sessions structured similarly
  • Children were allowed to take as long as desired in completing all sessions, but completing all sessions was required in the intervention group
  • Participants were loaned 24-inch iMac computers with the games and Microsoft Windows XP operating system pre-installed, but had no applications other than the video game interventions
  • Intervention coordinators monitored child use of the games by organizing and reviewing e-mail messages each time a child completed a session, answering call-in questions, guiding repair of minor hardware or software malfunctions, and arranging for timely repair of larger malfunctions.

Control group

  • Knowledge-enhancing Internet experience presented in two parts (one for Diab, one for Nano)
    • Each part included a booklet with two discs:
      • One disc with eight sessions of game-based Web sites (each related to diet, physical activity and obesity), with questions on the disc to be answered after each session (with immediate feedback)
      • Second disc contained knowledge-based nutrition game (Part 1: “Good Food and Play Make a Balance Day” and Part 2: “Dish It Up”) that was played with the eight session websites.

Statistical Analysis

  • Descriptive statistics
  • Pearson and Spearman correlations to assess associations between key variables
  • Mixed models analysis to examine whether children playing Diab and Nano increased fruits and vegetables intake, water intake or physical activity
    • Model contained time and group
    • Baseline included as covariate
    • Controlled for confounders: Demographics, social desirability of response, duration of game play.
Data Collection Summary:

Timing of Measurements

  • Baseline
  • Between games (Post 1)
  • Immediate post-game (Post 2)
  • Two months post-game (Post 3).

Dependent Variables

  • Fruit and vegetable intake measured by 24-hour dietary recall
  • Water intake measured by 24-hour dietary recall
  • Physical activity measured by accelerometer
  • Body composition measured by anthropometry.

Independent Variables

  • Time
  • Group.

Control Variables

  • Baseline measures of dependent variables
  • Demographic characteristics
  • Social desirability of response
  • Duration of game play.
Description of Actual Data Sample:
  • Initial N: 260 children initially contacted
  • Attrition (final N): 133 with complete data; 43.8% female
  • Age:
    • 10 years (42.5%)
    • 11 years (32.7%)
    • 12 years (24.8%)
  • Ethnicity:
    • White (40%)
    • African-American (24%)
    • Hispanic (28%)
    • Other (7.8%)
  • Other relevant demographics: Highest household education: 68.6% college degree or more
  • Anthropometrics: Despite randomization there were differences in
    • BMI percentile (79.6% Treatment vs. 74.2% Control)
    • BMI z-score (0.92 Treatment vs. 0.73 Control) by group at baseline
  • Location: Houston, TX.
Summary of Results:

Tests of Group and Group x Visit Interaction Terms from Mixed-model Repeated Measures ANCOVA

Diet (Servings) Group
F (P-value)
Group x Visit
F (P-value)
Fruits and vegetables 5.73 (0.018) 2.51 (0.083)
Fruits 10.93 (0.001) 3.57 (0.029)
Vegetables (excluding high fat vegetables like french fries) 0.44 (0.508) 2.45 (0.089)

The diet outcome analysis revealed significant treatment vs. control effects at all post-assessments on fruit and vegetable intake and its component F intake with the largest between-group difference in fruit and vegetable intake at Post-test 3 assessment. Treatment group increased intake of fruits and vegetables from 1.65 (baseline) to 2.15 (Post-test 3) servings per day.

Other Findings 

There were no significant effects for the other variables (water intake, physical activity or body composition). 

Author Conclusion:
  • Diab and Nano were designed as epic video game adventures, comparable to commercial-quality video games
  • These games incorporated a broad diversity of behavior change procedures woven in and around engrossing stories
  • The games motivated players to substantially improve diet behaviors
  • Fruit and vegetable intake and water consumption and physical activity were still below the minimum recommendations, indicating that more work is needed
  • Serious video games hold promise, but their effectiveness and mechanisms of change among youth need to be investigated more thoroughly.
Reviewer Comments:
  • Co-investigator Richard Buday is the President of Archimage, Inc., the company that created Diab and Nano. However, the objective nature of data collection and blinding of the data collectors to group assignment minimize the risk of compromise to study integrity.
  • While significant group differences existed in baseline main outcome measures, statistical analysis included baseline values in the models.

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?