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Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity
Published on: March 7, 2019
Intervention fidelity in a teacher-led program to promote physical activity in preschool-age children
Sofiya Alhassan1, Melicia C Whitt-Glover2
1Department of Kinesiology, University of Massachusetts Amherst, 110 Totman Building, 30 Eastman Lane, Amherst, MA 01003, USA.
Objective:
To examine protocol fidelity among teachers involved in a six-month cluster-randomized physical activity (PA) intervention.
Methods:
In 2011, preschools in Springfield, MA were randomized to short bouts of structured PA (SBS-PA, n=5) or unstructured playtime (UPA, n=5). SBS-PA provided structured PA in the classroom during the first 10 min of gross-motor playtime followed by 20 min of unstructured playtime. UPA consisted of 30 min of unstructured playtime. All teachers (SBS-PA and UPA) received a written study protocol and 1.5h of training. SBS-PA also received videos to use to lead structured PA and 1.5 additional hours of training. Study fidelity and process evaluation were assessed twice weekly via semi-structured questionnaire.
Results:
Only 56.6% of SBS-PA and 75.2% of UPA free playtimes lasted for 30 min; 86.3% of SBS-PA teachers implemented structured PA during the first 10 min of gross-motor playtime but only 67.2% delivered the intervention as instructed. Only 68.5% of SBS-PA teachers implemented the 20-minute unstructured playtime. SBS-PA teachers reported that time limitations was a major barrier in implementing the designed intervention. Pre-post changes in PA did not differ between groups.
Conclusion:
Limited fidelity to intervention protocol likely impacted study findings. Future studies should focus on strategies to improve adherence among intervention leaders.
