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Citation:

Neumark-Sztainer D, Story M, Hannan PJ, Rex J. New Moves: A school-based obesity prevention program for adolescent girls. Prev Med. 2003 Jul; 37(1): 41-51.

 


PubMed ID: 12799128
Study Design:
Cluster Randomized Trial
Class:
A - Click here for explanation of classification scheme.
NEUTRAL: See Research Design and Implementation Criteria Checklist below.
Research Purpose:

To test the feasibility of an innovative school-based program for obesity prevention among adolescent females that are overweight or at risk of becoming overweight. The program, New Moves, was a multi-component, girls-only, high-school physical education class.

Inclusion Criteria:
  • High schools within the Twin Cities school district area in Minnesota were included
  • Eligibility criteria of female participants included:
    • Adolescent females within the participating schools
    • Self-reported low physical activity with activity levels below 30 minutes per day, three days a week
    • Based on self-reported height and weight, those with body mass index values at the 75th percentile or higher for age and gender were given priority for participation.
Exclusion Criteria:
  • During screenings, females who had reported that:
    • A doctor had stated they had an eating disorder
    • Reported disordered eating (self-induced vomiting, diet pill use, laxative use, diuretic use) during the past month
  • The number excluded during screening, N=35.
Description of Study Protocol:

Recruitment

  • Study population included three intervention schools and three control schools from the Twin Cities  area school district
  • Because of logistics, students were recruited after schools were randomized. Therefore, participants of the New Moves program were aware of the program intervention.
  • Students in the control group were recruited to participate in a research project involving eating and exercise patterns of teens
  • Recruitment flyers and posters were used to promote, avoiding advertising program as one for overweight youth (due to potential labeling and scrutinization). Instead, it was advertised to entice female adolescents who were interested in becoming more active and healthy weight management promotion.
  • Active consent by both parents and students was received, and students completed an initial screening form.

 Design

Group randomized controlled trial:

  • Schools were randomly assigned to either an intervention or control group
  • Participants in the intervention received the New Moves program for one semester instead of participating in conventional physical education classes.

Blinding Used

Because of logistics, students were recruited after schools were randomized. Therefore, participants of the New Moves program were aware of the program intervention.

 Intervention

  • The New Moves program consisted of a semester-long program that the students participated in for credit. Social Cognitive Theory provided the framework for the program development.
  • The program addressed issues concerning: Socio-environmental, personal and behavioral factors and interactions between these. Physical activity was offered four times per week, and nutrition and social support sessions alternated every other week.
  • Each student received a personal manual of the program.

Statistical Analysis

  • Analyses were measured between control and intervention on the following: Change in physical activity, activity level; fruit and vegetable intake; soda intake; meals per day; body mass index; self-acceptance; athletic competence; self-worth; self-efficacy to be physically active; enjoyment of physical activity; benefits of physical activity and healthful eating; and peer, parental and staff support
  • Different analytic methods were used for the qualitative and quantitative data collected within each area
  • As part of the evaluation of the program, interviews with staff, teachers, parents and students were conducted.
Data Collection Summary:

Timing of Measurements

Measurements assessed at baseline, post-intervention and follow-up among the student participants (intervention vs. control). 

Dependent Variables

  • Behavioral variables: Physical activity change, physical activity amount, sedentary activity amount, fruit and /vegetable intake, soda intake, breakfast consumption, fast food consumption, weight control behaviors and binge eating. All of these were assessed with a self-reported questionnaire.
  • Personal variables: body mass index, self-acceptance, athletic competence, physical appearance, self-worth, media internalizaion, benefits of physical activity and healthful eating, enjoyment of physical activity, self-efficacy to be physically active. All of these, except BMI, were assessed with a self-reported questionnaire.
  • Socio-environmental variables: Perceived parental support, peer support and staff support. All were assessed with a self-reported questionnaire.

Independent Variables

New Moves intervention program offered in place of conventional physical education class. 

Description of Actual Data Sample:
  • Initial N:
    • 201 girls at baseline from intervention and control schools
    • 190 girls participated at post-intervention for a response rate of 94% (95% in control and 92% in intervention)
    • 180 girls participated in the eight-month follow-up for a response rate of 89% (88% in control and 89% in intervention) from baseline to follow-up
  • Attrition (final N):
    • 180 girls participated in the eight-month follow-up for a response rate of 89% (88% in control and 89% in intervention) from baseline to follow-up
    • Attrition reasons include moving out of the school district or state, suspension from school, drug rehabilitation, severe illness and no-shows or refusals
    • Responders and non-responders did not differ at baseline across age, race/ethnicity and body mass index
  • Age: Most were ninth and tenth grade females (14 to 16 years of age); mean age 15.4±1.1
  • Ethnicity:
    • Mixed background including: White (41.9%), African American (28.6%), Asian American (21.1%), Hispanic (4.4%), Native American (1%) and mixed/other (3%)
    • Higher percentage of white girls in the intervention; higher percentage of Asian Americans in the control group
  • Anthropometrics:
    • Total BMI: 26.7±6.5
    • Intervention group BMI: 27.6±7.2
    • Control group BMI: 25.9±5.8
  • Location: Twin Cities area school district in Minnesota.
Summary of Results:

Key Findings

  • The feasibility of implementing New Moves was high, as indicated by strong satisfaction among participants, parents and school staff, and by program sustainability
  • Participants perceived a positive program impact on their physical activity, eating patterns and self-image
  • Girls in the intervention significantly progressed in their stage of behavioral change for physical activity from baseline to follow-up
  • At post-intervention, 20% of the control progressed in their stage of physical activity and 24% regressed. In contrast, 31% of the intervention progressed and 19% regressed.
  • At follow-up, the corresponding percents changes in stage were effectively unchanged in the control, but were enhanced in the intervention: 38% progressed while only 11% regressed
  • No differences in body mass index at post-intervention or follow-up
  • For the majority of the outcome measurements, differences between the intervention and the control were not statistically significant.
Author Conclusion:

The intervention program, New Moves, was well received and fills a needed niche within the school physical education programs. An expanded intervention and evaluation is needed to enhance and assess long-term program effectiveness.

Reviewer Comments:

Significant differences between groups at baseline. Authors note the following limitations:

  • Longer or more intensive interventions may be needed to achieve substantial changes in outcome variables such as eating behaviors, physical activity and BMI
  • Limited statistical power to detect changes due to small number of participating schools
  • Lack of measures sensitive to changes in body composition
  • Use of self-report measures to assess variables such as physical activity
  • Short follow-up period, which did not allow for the detection of the prevention of weight gain over time
  • Girls were aware of the study condition prior to signing up for study participation, and this may have contributed to baseline differences between groups of girls.

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?
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?
No
  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?
No
  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%.)
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?
Yes
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?
Yes
  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.)
No
  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?
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?
???
  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?
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?
Yes
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).