Although social support is integral to the coaching process, there is only a limited understanding of the antecedents of perceived coach support. We applied generalizability theory to examine perceived coach support and its antecedents at perceiver, provider, and relational levels of analysis. Two studies were conducted in which athletes rated the degree to which they identified with a selection of coaches, and the personality, competency, and supportiveness of those coaches. Univariate analyses demonstrated that the relational component accounted for a significant amount of variance in perceived coach support in both studies. Multivariate analyses demonstrated that when athletes perceive specific coaches to be highly agreeable, competent, and individuals with whom they share a common identity, they also perceive these same coaches to be particularly supportive in comparison with other coaches.
Adam Howard Coussens, Tim Rees, and Paul Freeman
Fadi M. Al Zoubi and Richard A. Preuss
Measuring lumbar spine range of motion (ROM) using multiple movements is impractical for clinical research, because finding statistically significant effects requires a large proportion of subjects to present with the same impairment. The purpose of this study was to develop a single measure representing the total available lumbar ROM. Twenty participants with low back pain performed three series of eight lumbar spine movements, in each of two sessions. For each series, an ellipse and a cubic spline were fit to the end-range positions, measured based on the position of the twelfth thoracic vertebra in the transverse plane of the sacrum. The area of each shape provides a measure of the total available ROM, whereas their center reflects the movements’ symmetry. Using generalizability theory, the index of dependability for the area and anterior-posterior center position was found to be 0.90, but was slightly lower for the mediolateral center position. Slightly better values were achieved using the spline-fitting approach. Further analysis also indicated that excellent reliability, and acceptable minimal detectable change values, would be achieved with a single testing session. These data indicate that the proposed measure provides a reliable and easily interpretable measure of total lumbar spine ROM.
Tim Rees, Paul Freeman, Steve Bell, and Ross Bunney
Coaches are important providers of social support, but what influences us to perceive our coaches as supportive or unsupportive? We investigated the extent to which perceptions of coach support reflect characteristics of athletes and coaches, as well as relational components. In three studies, athletes judged the actual or hypothetical supportiveness of various coaches. The methods of generalizability theory permitted us to conclude that perceptions of coach support primarily reflected relational components, with characteristics both of athletes and coaches also independently playing (lesser) roles. These findings suggest that athletes may systematically disagree on the supportiveness of their coaches.
Elizabeth A. Holbrook, Minsoo Kang, and Don W. Morgan
As a first step toward the development of adapted physical activity (PA) programs for adults with visual impairment (VI), the purpose of this study was to determine the time frame needed to reliably estimate weekly PA in adults with VI. Thirty-three adults with VI completed 7 days of pedometer-based PA assessment. Generalizability theory analyses were conducted to quantify sources of variance within the PA estimate and determine the appropriate number of days of PA monitoring needed for the total sample and for participants with mild-to-moderate and severe VI. A single-facet, crossed design was employed including participants and days. Participants and days correspondingly accounted for 33–55% and 0–3% of the total variance in PA. While a reliable account of PA was obtained for the total sample over a 6-day period, shorter (4-day) and longer (9-day) periods were required for persons with mild-to-moderate and severe VI, respectively.
Youngdeok Kim, Ilhyeok Park, and Minsoo Kang
The purpose of this study was to investigate rater effects on the TGMD-2 when it applied to children with intellectual disability. A total of 22 children with intellectual disabilities participated in this study. Children’s performances in each of 12 subtests of the TGMD-2 were recorded via video and scored by three adapted physical activity specialists who have expertise in the TGMD-2. Two advanced measurement theories, Generalizability-theory (G-theory) and many-facet Rasch model (MFRM), were applied in data analyses. There were relatively large variances attributed to rater effects on the scores of the TGMD-2 awarded to children with intellectual disabilities. The severity of each rater significantly differed across all subtests of the TGMD-2. There was a set of biased ratings interacted with measurement conditions of the TGMD-2.
Dale A. Ulrich and Steven L. Wise
This study was designed to investigate the reliability of individual and composite scores obtained with the Objectives-Based Motor Skill Assessment Instrument. Generalizability theory was used to determine if the test scores were reliable across raters and occasions. Two D studies were conducted to ascertain whether an increase in the number of raters from 10 to 20 would increase the reliability. Twenty raters were required to evaluate the fundamental motor skills of 10 subjects across two occasions from videotapes. In 92% of the individual skill scores, the between-subject variance component contributed the most to total variance. Therefore, it can be concluded that the test is extremely reliable across raters and occasions. Examination of the generalizability coefficients for the two D studies indicates that the reliability is not largely affected by increasing the number of raters.
Leona J. Holland, Marcel Bouffard, and Denise Wagner
The reliability of oxygen consumption (VO2), heart rate (HR), and rating of perceived exertion (RPE) at three different workloads was examined during an arm cranking exercise task. Nine persons with multiple sclerosis (MS) and confined to a wheelchair each performed two sessions of discontinuous, submaximal aerobic test on an arm ergometer. Comparisons of the test scores and generalizability theory were used to analyze the data. Both HR and VO2 were found to be reliable measures under the conditions used in this study. RPE at the same workloads was found to be rather unreliable. Overall, the use of RPE as an indicator of exercise intensity instead of HR appears to be unjustified by the results of this study. Therefore, practitioners who want a quick and efficient method of measuring exercise intensity should use HR instead of RPE for persons with multiple sclerosis.
Werner F. Helsen, Janet L. Starkes, and Nicola J. Hodges
Two studies tested the theory of deliberate practice (Ericsson, Krampe, & Tesch-Romer, 1993) and contrasted results with the sport commitment model (Scanlan, Carpenter, Schmidt, Simons, & Keeler, 1993a, 1993b). In Part I, international, national, and provincial soccer and field hockey players recalled the amount of time they spent in individual and team practice, sport-related activities, and everyday activities at the start of their career and every 3 years since. In Part II, these activities were rated in terms of their relevance for improving performance, effort and concentration required, and enjoyment. A monotonic relationship between accumulated individual plus team practice and skill level was found. In contrast with Ericsson et al.’s (1993) findings for musicians, relevant activities were also enjoyable, while concentration became a separate dimension from effort. The viability of a generalized theory of expertise is discussed.
E. Andrew Pitchford and Joonkoo Yun
Pedometers are a common instrument used to measure walking activity, yet reliability evidence in disability populations, particularly Down syndrome (DS), has received little attention. There may be systematic and random sources of error that could influence reliability under natural walking conditions. The purpose of this study was to examine the sources of variance and estimate reliability coefficients of spring-levered (SL) and piezoelectric (PZ) pedometers for adults with DS during a free-walking bout.
Seventeen adults with DS and 23 adults without a disability walked continuously for a 20-minute period wearing 2 types of pedometers, SL and PZ. Step counts were analyzed using Generalizability theory to partition and quantify variance components and calculate reliability coefficients.
The largest variance component was due to individual participant differences. Adults with DS demonstrated greater intraindividual variability, but also had relatively low proportions of residual variance, or unexplained error. The SL pedometer showed problems with interunit variance while the PZ pedometer demonstrated little systematic error. Reliability coefficients were consistently higher for the PZ pedometer.
This study found minimal systematic error and moderate reliability evidence for the PZ pedometer. This type of pedometer may be used in future research for adults with DS.
Minsoo Kang, Youngdeok Kim, and David A. Rowe
This study examined the optimal measurement conditions to obtain reliable peak cadence measures using the accelerometer-determined step data from the National Health and Nutrition Examination Survey 2005–2006.
A total of 1282 adults (> 17 years) who provided valid accelerometer data for 7 consecutive days were included. The peak 1- and 30-minute cadences were extracted. The sources of variance in peak stepping cadences were estimated using Generalizability theory analysis. A simulation analysis was conducted to examine the effect of the inclusion of weekend days. The optimal number of monitoring days to achieve 80% reliability for peak stepping cadences were estimated.
Intraindividual variability was the largest variance component of peak cadences for young and middle-aged adults aged < 60 years (50.55%–59.24%) compared with older adults aged ≥ 60 years (31.62%–41.72%). In general, the minimum of 7 and 5 days of monitoring were required for peak 1- and 30-minute cadences among young and middle-aged adults, respectively, whereas 3 days of monitoring was sufficient for older adults to achieve the desired reliability (0.80). The inclusion of weekend days in the monitoring frame may not be practically important.
The findings could be applied in future research as the reference measurement conditions for peak cadences.