Date of Award
Doctor of Philosophy
School of Exercise and Health Sciences
Faculty of Health, Engineering and Science
Associate Professor Angus Burnett
Professor Rob Newton
The capability of a golfer to record a low score depends upon well-developed abilities in each of the recognised on-course skill components (driving the ball off the tee, hitting approach-iron shots, hitting short-iron shots and putting). Despite approach-iron play being considered perhaps the most important and definitely the most practiced skill in the game, the ability to quantify the golfer’s ability to hit approach-iron shots in a controlled, off-course environment (eg. training) cannot yet be undertaken due to the lack of appropriate assessments. Such tools have considerable potential for use in both the field and in research for implementation in intervention studies, monitoring of athlete improvements over time as well as for use in talent identification programs. In this doctoral thesis which consisted of five studies, two testing instruments (Nine-Ball Skills Test and the Approach-Iron Skill Test) were developed to assess approach-iron ability, and their measurement properties (eg. reliability, validity) were determined.
In the first study of this thesis, the Nine-Ball Skills Test was developed to assess the ability of golfers to shape and control the golf ball whilst attempting to maximise accuracy. In this study, golfers (elite, n = 14; high-level amateur, n = 16) hit a series of nine shots with a 5-iron with differing combinations of trajectory (straight, fade, draw) and height (normal, high, low) at a predetermined target area. The scoring system in this test predominantly relied upon the accuracy of each of these shots via a commonly used performance indicator called the percent error index (PEI). This is a measure which is based around the resultant distance the ball lands from the hole of which its components are determined by a real time Doppler radar launch monitor.
In the second study, the Approach-Iron Skill Test was developed as a second measure of approach-iron ability in high performance golfers. The test differed from the protocol used in the first study in that players (elite, n = 26; high-level amateur, n = 23) were requested to hit a series of three straight shots using a club of their choice to a target placed at nine different distances (55, 65, 75, 85, 95, 105, 125, 145, 165 m). Each shot in this test was scored using the same PEI method as used in Study 1. For a test to be truly useful in the practical arena there needs to be evidence of its reliability and validity. Both the Nine-Ball Skills Test (Study 1) and the Approach-Iron Skill Test (Study 2) showed fair to good test re-test reliability respectively. Additionally, both tests were assessed for content validity and showed a very good level of construct validity (discriminative) between elite and high-level amateur players.
In the third study, the ability of high-level amateur players to estimate the distances of approach-iron shots was investigated. This ability is important for high-level and elite players for the purposes of performance analysis and longitudinal collection of on-course, competition-based data. The main aim of this study was to assess the accuracy and precision of distance measurements made for approach-iron shots by high-level players in actual on-course play. Four measurements (Distance to Hole, Approach Shot Distance, Ball to Hole Distance and PEI) were assessed for their agreement with known distances obtained from a laser rangefinder and/or steel retractable tape measure during actual tournament play. All four measures investigated in the study showed a good level of agreement with known distances and reported low root mean square errors of prediction.
In the fourth study, a systematic review of development and assessment methods of sporting skill outcome tests was undertaken. The objective of this study was to systematically review methodological quality, measurement properties (reliability, validity, responsiveness) as well as the feasibility of skill outcome tests. From analysis of the 22 studies that were selected after meeting the inclusion and exclusion criteria, it was found that the majority of studies were of adequate methodological quality. Further, whilst the studies adequately investigated test-retest reliability as well as content and construct validity, criterion-related validity (in particular, predictive validity) was not investigated in the majority of the assessments. Further, responsiveness was not investigated in the majority of studies and the reporting of feasibility considerations was minimal. A framework for sporting skill test design based on the findings of the review as well as existing measurement theory literature was also recommended for the benefit of future studies.
In the final study of the thesis, the convergent and predictive validity of both the Nine-Ball Skills Test and the Approach-Iron Skill Test was investigated. A group of highlevel amateur golfers (n = 24) initially undertook both tests during the space of one week. Following this, data relating to their approach-iron performance in tournament scenarios (most notably, PEI) was collected over a 90-day period. A moderate correlation was noted between scores for both skills tests. Further, using generalised estimating equations (controlling for both the lie of the ball and shot distance) it was shown that both the Approach-Iron Skill Test and the Nine-Ball Skills Test were significant predictors of oncourse approach-iron performance. The Approach-Iron Skill Test showed a strong ability to predict on course approach-iron performance.
The original and innovative studies within this thesis certainly have practical significance for golfers and coaches near, and inclusive of, the elite end of golf. The development of golf skill tests displaying good measurement properties help to provide useful tools for use by researchers, coaches and players to assess ability in approach-iron play. Future study should focus on developing similar protocols for the remaining components of performance to golf, using the development methods and measurement characteristics examined in this thesis as a template for design.
Chapters 2, 3, 4, 5 an 6 are not available in this version of the thesis.
Robertson, S. J. (2013). Approach-iron play in high performance golf: From testing to tournament play. https://ro.ecu.edu.au/theses/2332