PEDS 409 Research Design: True Experimental

1. PEDS 409 Research Design: True Experimental BY: Sherri Beauchamp, Marie Buchta, Avaleigh Wagner & Jodi Spink

2. Li, F. et al. (2001) Tai Chi Enhances Self-Efficacy and Exercise Behavior in Older Adults. Journal of Aging and Physical Activity (9): 161-171.

3. Authors and Affiliations • Fuzhong Li: Oregon Research Institute • Edward McAuley • Peter Harmer • Terry E. Duncan • Nigel R. Chaumeton • Grants from: National Institute on Drug Abuse and National Institute on Aging

4. Research Question • What are the effects of a Tai Chi intervention program on perceptions of personal efficacy and exercise behavior in older adults?

5. Type of Research • True Experimental • One or more control groups AND one or more treatment groups • Random assignment from population of interest • Variables of interest can be manipulated directly

6. Type of Research (con’t) • Randomized Control Trial Design R O1 X1 O2 X2 O3 R O1 O2 O3 • R = Randomized Samples • O1-3 = Observations • X1-2 = Tai Chi intervention

7. Type of Research (con’t) • Advantages • Good for assessing change during and after intervention • Main threats are controlled (testing, maturation etc.) • Disadvantages • Attrition rates • Diffusion of intervention (ie control group increases activity) • Resentment for no intervention

8. Research Methods • Individuals responded to newspaper ads and flyers at senior centers • Inclusion criteria • 65 years of age or older • Low active according to PASE (Physical Activity Scale for the Elderly)– no involvement in regular exercise program within the last month • Healthy – exercise will not have negative physical effects • Willingness to be randomly assigned

9. Research Methods (con’t) • 98 individuals 65-96 years old were chosen • Assigned to either a Tai Chi practice group or a waiting list • Assessed demographic characteristics: age, gender, education, income & ethnicity • 6 month trial

10. Intervention group Yang Style Tai Chi 60 min. practice sessions 2x/week for 6 months 15 min. warm up, 15 min cool down included in practice session Control Group Maintained routine activities Could not join new exercise programs Promised a 4 week Tai Chi program at the end Research Methods (con’t)

11. What is Yang Style Tai Chi? Yang Style Tai Chi is a slow moving form that affects balance postural alignment & concentration

12. Barrier scale self-efficacy 5 items to assess perception of ability to perform Tai Chi regularly in the face of barriers (ie. Pain, boredom etc.) 0-100 confidence scale (0=very little confidence, 100=complete confidence) Performance scale self-efficacy 3 item task-specific, time-based Degree of confidence in ability to successfully perform a series of slow, rhythmically changing body position movements 0-100 confidence scale Research Methods (con’t):Outcome Measures

13. Outcome Measures con’t • Class Attendance • Exercise behavior was assessed by attendance taken by instructor • Frequency of Measurements • Baseline measures - prior to study • 2nd measures – week 12 • 3rd measures – week 24 (intervention group responded in class within 1 week, control group responded by mail)

14. Main Findings • Tai Chi exercise program can significantly enhance perceptions of task-specific personal efficacy in older adults • The Tai Chi group developed higher perceptions of efficacy, adhered better to the exercise program and spent more time engaged in exercise (therefore increased exercise participation)

15. Intervention (Tai Chi) group Both types of efficacy increase over time Initial boost from baseline to 2nd observation Maintenance from 2nd to 3rd observation Class attendance was significantly predicted by the changes in the 2 types of efficacy Control group Both types of efficacy decreased over time Main Findings (con’t)

16. Main Findings (con’t) Change in barrier efficacy between Tai Chi and Control Change in performance efficacy between Tai Chi and Control

17. Brief Critique • All subjects were volunteers – this could make generalizability difficult • Gender was recorded but not specified in results – potential influence of a moderator variable • Monitoring attendance issues – no parameters set aside for absenteeism - assumption that absenteeism is due to self-efficacy • All self-efficacy measures are self-reported therefore subject to social desirability biases

18. Brief Critique (con’t) • Physical activity in control group was not monitored throughout the study • No data comparing the decrease in self-efficacy to a decrease in activity • Motivation issue – feel obligated to attend because are in the study • Would participants attend these classes if not in the study? (long term adherence) • Validity of claim: intervention should be compared to other organized activities/classes

19. Brief Critique (con’t) • Ethical issues: Control group was only offered a 4 week Tai Chi class after the study, whereas intervention group got 6 months • Self-efficacy measures are based on performance of Tai Chi not general daily activity (not applicable to control group) • Warm up and Cool down not specified • Sample size decreased due to attrition which could impact generalizability

20. Future Research Suggestions • Compare Tai Chi results to more Traditional forms of exercise (ie. Strength training, walking, stretching, etc.). • Compare positive effects of Tai Chi in other age groups. • Look at adherence over longer periods of time or post-intervention (months, years later)

21. Future Research Suggestions (con’t) • Impact of Tai Chi on health & related aging problems as compared to other activities/interventions. • Examine impact of Tai Chi on adherence to/participation in activities of daily living

22. Other questions that can be addressed with True Experimental Research • Can be used for any study involving an intervention (ie. Drug, exercise, acupuncture, rehabilitation therapy, any lifestyle factor etc.) on a sample of a specific population

23. THE END