RELATIVE PAY-OFFS FOR INTERVENTIONS THAT FOCUS ON INDIVIDUALS VERSUS THE ENVIRONMENT

1. RELATIVE PAY-OFFS FOR INTERVENTIONS THAT FOCUS ON INDIVIDUALS VERSUSTHE ENVIRONMENT Debbe Thompson, PhD Children’s Nutrition Research Center Baylor College of Medicine October 27, 2004 October 18, 2004

2. Overview • Presentation focus = school based obesity prevention programs • Report results of a literature review conducted to identify effective intervention approaches and features • Offer suggestions for future directions

3. Why Focus on Schools? • Over 90% of youth attend school • Schools offer curricular, PE, and SFS that can be tapped to address the issue • Social networks exist that can support behavior change • Established communication channels can be utilized to promote messages • Longterm interventions can be conducted

4. Categories of School-Based Obesity Prevention Programs • Individual focus • Curriculum based • Change individual characteristics • Focus on behavior – often outside of school • Environmental focus • Change school environment – PE, SFS • Focus on in-school behavior • Combined focus • Selected features of both approaches

5. What Works? • Reviewed literature to: • Determine if programs with an individual, environmental, or combined focus are more likely to be effective in a school-based setting • Identify differences between programs that achieve change in body composition and those that do not • Features of successful programs

6. Inclusionary Criteria • Content Criteria • Focus on diet, physical activity, and/or physical inactivity • Body composition as dependent variable • Emphasized prevention, not treatment • Method Criteria • Experimental design (randomization) • School was unit of randomization & analysis • Appropriate statistical analysis methods

7. Results • Individual Focus • 8 • 2 changed body composition (25%) • Environmental Focus • 2 • 1 changed body composition (50%) • Combined Focus • 1 • 0 changed body composition (0%)

8. Overview of Findings • Literature was difficult to summarize or evaluate • No common convention for reporting results • Lots of variability in program components and level of detail provided • Variability in program effect

9. Successful Programs Legend: PA = physical activity I = Individual focus PIA = physical inactivity E = Environmental focus

10. Successful Programs Legend: PA = physical activity I = Individual focus PIA = physical inactivity E = Environmental focus

11. Conclusion • No conclusions could be drawn regarding: • Most successful approach in a school setting • Differences between effective and ineffective interventions

12. Recommendation • Adopt Transparent Reporting of Evaluations with Nonrandomized Designs (TREND) statement • Provides a standard reporting structure • Enhances ability to compare diverse studies and to identify effective intervention components

13. Where do we go from here?

14. Future Directions (1) • Elucidate effective intervention components • Conduct single theory/single mechanism research to identify: • behavior change components most likely to lead to success • mechanisms that show promise for behavior change • Understanding single effects more clearly can enhance multi-theoretical approaches

15. Example:Food, Fun, & Fitness Club • 8 wk Internet based program promoting healthy diet and PA behaviors to 8-10 year old African American girls • Goal • determine the effect of reinforcement schedule on log on rate, behavior, and mediating variables • Why important • log on rate controls dose • understanding effect of reinforcement schedule on log on rate increases potential for a more effective intervention

16. Future Directions (2) • Refine measurement approach, methods, and tools • Establish item pools for key variables (IRT) • Utilize computerized testing to tailor item difficulty to ability (need fewer items) • Follow common administration protocols to ensure consistency in measurement

17. Example: FJV SE Questionnaire • Analysis • CTT – met usual criteria • IRT – limited item range • IRT holds promise for: • Enhancing quality of measurement • Reduced participant burden • Example: Computer Adaptive Testing

18. Future Directions (3) • Critically examine approach to research • Focus on translational research (e.g., from basic to applied research)

19. Example: Fitness Zone • Study goal: • To understand how design features in computer-based interventions impact program effect • Outcome variables: PA self efficacy, PA intention, and depth of information processing • Examines: • Presentation format (text-based fact sheets vs manga-style comics) • Processing channel (visual and/or verbal) • Potential impact: • Results can be used to design more efficient and effective computer-based interventions

20. Concluding Remarks • Schools provide an important channel for reaching large numbers of youth • School based obesity prevention programs can achieve change in body composition • More work is needed to determine the most effective methods for achieving change

21. Thank you!