Year of Publication


Degree Name

Doctor of Philosophy (PhD)

Document Type

Doctoral Dissertation


Health Sciences


Rehabilitation Sciences

First Advisor

Dr. Timothy L. Uhl

Second Advisor

Dr. Robert A. English


Traditional sports science motion analysis techniques using three-dimensional (3D) kinematics have demonstrated that proper mechanics enhance serve performance and improper mechanics overload tissues resulting in injury. However 3D analysis is costly, time-consuming, and requires extensive knowledge of biomechanical properties and data analysis. Currently there are no simple, reliable, and valid observational methods for health care providers (HCP) and tennis professionals to evaluate tennis serve mechanics. Researchers investigating observational analyses have determined that superior reliability may be a result of specific operational definitions and the incorporation of educational training sessions on how to perform the analysis.

The first purpose of this dissertation was to investigate the reliability of an observational tennis serve analysis (OTSA) tool between two HCPs that helped create the analysis method. The OTSA assesses nine key body positions/motions during the service motion. These specific body positions have been called “nodes.” The second purpose was to determine the OTSA reliability in a group of novice users unfamiliar with the analysis method undergoing two different forms of instructional training. The third purpose was to determine the discriminant and convergent validity of the OTSA in grading tennis serve mechanics among tennis players using the national tennis ranking program commonly used in the United States to evaluate level of tennis play.

The first study demonstrated that reliability of the OTSA ranged from 0.36-1.0 across the nodes, with five out of the nine nodes displaying substantial reliability (>0.61). In the second study results demonstrated there were no statistical differences in the intra-observer reliability values between the two instructional training groups. Additionally, the majority of the inter-observer kappa values were not statistically different between the two instructional training groups. In the third study, six of the nine nodes were able to discriminate between high and low ranked tennis players. Additionally, there was a strong correlation between the OTSA and ranking level, indicating that there is convergent validity and supports the construct of the OTSA as deficits in the service motion are associated with lower ranked tennis players. These results suggest that nearly all of the nodes associated with the OTSA are reliable and valid and can be used to assess tennis serve mechanics.

Digital Object Identifier (DOI)