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Citation:

Casazza K, Ciccazzo M. The method of delivery of nutrition and physical activity information may play a role in eliciting behavior changes in adolescents. Eat Behav. 2007 Jan;8(1):73-82.


PubMed ID: 17174854
Study Design:
Nonrandomized Group Trial
Class:
C - Click here for explanation of classification scheme.
NEUTRAL: See Research Design and Implementation Criteria Checklist below.
Research Purpose:

This study was conducted to determine which health education delivery method (computer based or traditional education) would elicit a greater behavior change.

Inclusion Criteria:

School administrators granted permission and students and parents gave consent.  Only students with elective classes were solicited, and only those with complete data sets were included in the final analysis. 

Exclusion Criteria:

None specifically mentioned.

Description of Study Protocol:

Recruitment  Students meeting the inclusion criteria were solicited in this convenience sample.

Design Nonrandomized group trial.  Students participated at three schools:  a control (CON) school, a traditional education school (TDI) and a computer-based education school (CBI).  

Blinding used (if applicable)  not applicable

Intervention (if applicable)

  • CBI: A nutrition education CD-ROM with 5 sessions of 45 minutes each was designed by the investigator for use in this study.
  • TDI: The investigator taught the classes via lecture using the same time frame and content outline as the CD-ROM.

Statistical Analysis Repeated measures ANOVA was used to test equality of means. 

 

Data Collection Summary:

Timing of Measurements  Data were collected over 16 weeks.  Outcome measures were collected at weeks 1-3 and weeks 13-16.  Post-test evaluations were completed 11 weeks after baseline due to public school schedule.   

Dependent Variables

  • BMI
  • Food intake measured through 24-hr recall (2 non-consecutive days) and food frequency questionnaire (FFQ)
  • Validated nutrition knowledge questionnaire
  • Physical Activity Questionnaire for Adolescents (PAQ-a)
  • Dietary and exercise confidence surveys
  • Social support survey

Independent Variables

  • Nutrition education via CBI or TDI

Control Variables

 

Description of Actual Data Sample:

Initial N: 311 adolescent volunteers, 65.8% female

Attrition (final N): 275 completed all sessions and data collection

Age: Mean age 15.79 (13-18 years)

Ethnicity: Non-Hispanic black 51.6%, Hispanic 24%.

Other relevant demographics:

Anthropometrics

Location: Southern Florida

 

Summary of Results:

Key Findings

  • While there was no significant difference in BMI between the groups at baseline, the CBI group had a decrease in BMI from pre to post (23.1 ±0.7 to 22.9 ±0.7, P<0.001.)
  • There was a significant increase in knowledge among both the CBI group and the TDI group, but no difference between the groups.
  • The CBI group had a significant increase in physical activity (17.6 ±5.92 to 19.6 ±5.82, P=0.005.)
  • There was a decrease in total calories consumed by both intervention groups at post-test compared to baseline (P=0.006 CBI; P=0.009 TDI).  There were no differences in individual nutrients.
  • The CBI group reduced the number of meals skipped (P=0.001).
  • Both intervention groups showed a significant increase in perceived dietary social support for both their family and friends (P=<0.001) and for exercise social support from friends (P=0.007.)
  • The CBI group showed a significant increase from pre to post in their perceived ability to make better dietary choices such as decreasing salt and substituting healthy foods.  This did not differ from the TDI group.
  • There was no significant difference between the intervention groups in their satisfaction rating of the education sessions. 
Author Conclusion:

While the CBI elicited an overall greater change in behavior, no one method is the best for all students.  A multi-component model may be the best way to reach a wide range of students.  To curb drastic increases in overweight/obesity and chronic diseases we must focus on the learning styles of today's adolescents. 

Reviewer Comments:

Authors note the following limitations:

  • Participants used were based on a convenience sample, limited by schools' willingness to participate, teacher's willingness to let participants miss class time, and by those who volunteered for the study, limiting generalizability
  • Study was limited in the duration that it was allowed to occur; no contact with students for research purposes was permitted from January to March due to FCAT
  • Although the CBI group stated they preferred computer-based to traditional didactic education, they did not actually receive this information didactically and were reporting solely on their perceived preference

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)
Yes
  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 nutrition or dietetics practice?
Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies)
Yes
 
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?
No
  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?
No
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)
No
  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 used? (Concurrent preferred over historical controls.)
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 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.)
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%.)
No
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for?
Yes
  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?
N/A
5. Was blinding used to prevent introduction of bias?
Yes
  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.)
Yes
  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?
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?
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?
Yes
  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
 
 

Copyright American Dietetic Association (ADA).