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Sakiko Oyama, Araceli Sosa, Rebekah Campbell and Alexandra Correa

Video recordings are used to quantitatively analyze pitchers’ techniques. However, reliability and validity of such analysis is unknown. The purpose of the study was to investigate the reliability and validity of joint and segment angles identified during a pitching motion using video analysis. Thirty high school baseball pitchers participated. The pitching motion was captured using 2 high-speed video cameras and a motion capture system. Two raters reviewed the videos to digitize the body segments to calculate 2-dimensional angles. The corresponding 3-dimensional angles were calculated from the motion capture data. Intrarater reliability, interrater reliability, and validity of the 2-dimensional angles were determined. The intrarater and interrater reliability of the 2-dimensional angles were high for most variables. The trunk contralateral flexion at maximum external rotation was the only variable with high validity. Trunk contralateral flexion at ball release, trunk forward flexion at foot contact and ball release, shoulder elevation angle at foot contact, and maximum shoulder external rotation had moderate validity. Two-dimensional angles at the shoulder, elbow, and trunk could be measured with high reliability. However, the angles are not necessarily anatomically correct, and thus use of quantitative video analysis should be limited to angles that can be measured with good validity.

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Lawrence R. Brawley, Albert V. Carron and W. Neil Widmeyer

The process of validating a recently developed instrument to assess perceived team cohesion is discussed. The Group Environment Questionnaire (GEQ), an instrument designed to measure cohesion in sport teams, has good estimates for its internal consistency and for its content and factorial validity (Carron, Widmeyer, & Brawley, 1985; Widmeyer, Brawley, & Carron, 1985). However, other aspects of its validity required examination. The present article reports three studies concerning inspection of the GEQ's concurrent (Study 1), predictive (Study 2), and construct (Study 3) validities. In Study 1 the GEQ exhibited the predicted correspondence with similar measures of cohesion and was not significantly correlated with measures of other constructs. In Study 2 the GEQ successfully discriminated team and individual sport athletes by predicting their membership to these groups on the basis of their task cohesion scores. As well, classification of athletes as new and long-standing members of individual sport teams was predicted on the basis of their social cohesion scores. Finally, in Study 3 evidence was obtained for the predicted difference in self-responsibility attributions between high and low task-cohesive athletes of team sports. Considering the results of the three studies with previous evidence of content and factorial validity, the conclusion was that the GEQ is valid. In sum, demonstrations of the GEQ's content, factorial, concurrent, predictive, and construct validity reflect the ongoing process of its construct validation.

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Kathleen Simpson, Beth Parker, Jeffrey Capizzi, Paul Thompson, Priscilla Clarkson, Patty Freedson and Linda Shannon Pescatello

Background:

Little information exists regarding the psychometric properties of question 8 (Q8) of the Paffenbarger Physical Activity Questionnaire (PPAQ) to assess exercise. Thus, we conducted 2 studies to assess the validity and test–retest reliability of Q8 among adults.

Methods:

Study 1 participants (n = 419) were 44.1 ± 16.1 years of age. Validity was determined by comparing self-reported hr·d−1 in sedentary, light, moderate, and vigorous intensity physical activity (PA) and MET-hr·wk−1 on Q8 at baseline to accelerometer and health/fitness measurements using Spearman rank-order correlations. Study 2 participants (n = 217) were 44.7 ± 16.3 years of age and completed Q8 at baseline, 3 months, and 6 months. Test–retest reliability was determined using repeated measures analysis of covariance, intraclass correlations (ICCs), and standard error of the measurement (SEM).

Results:

Q8 displayed good criterion validity compared with accelerometer measurements (r = .102 to .200, P < .05) and predictive validity compared with health/fitness measurements (r = –.272 to .203, P < .05). No differences were observed in self-reported hr·d−1 in any of the PA categories at baseline, 3 months, and 6 months (ICC: 0.49 to 0.68; SEM: 1.0 to 2.0; P > .05), indicating good reliability.

Conclusion:

Q8 demonstrates adequate criterion validity, acceptable predictive validity, and satisfactory test–retest reliability and can be used in conjunction with other components of the PPAQ to provide a complete representation of exercise.

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Stephen J. Kelly, Aron J. Murphy, Mark L. Watsford, Damien Austin and Michael Rennie

Purpose:

To investigate the validity and reliability of accelerometry of the SPI-ProX II dual data logger (GPSports, Canberra, Australia).

Methods:

Controlled laboratory assessments determined the accuracy and reproducibility of raw accelerometer data. Intra- and interdevice reliability assessed the ability of the SPI-ProX II accelerometers to repeatedly measure peak gravitational accelerations (g) during impact-based testing. Static and dynamic validity testing assessed the accuracy of SPI-ProX II accelerometers against a criterion-referenced accelerometer. Dynamic validity was assessed over a range of frequencies from 5 to 15 Hz.

Results:

Intradevice reliability found no differences (P < .05) between 4 SPI-ProX II accelerometers, with a low coefficient of variation (1.87–2.21%). SPI-ProX II accelerometers demonstrated small to medium effect-size (ES) differences (0.10–0.44) between groups and excellent interdevice reliability, with no difference found between units (F = 0.826, P = .484). Validity testing revealed significant differences between devices (P = .001), with high percentage differences (27.5–30.5%) and a large ES (>3.44).

Conclusions:

SPI-ProX II accelerometers demonstrated excellent intra- and interaccelerometer reliability. However, static and dynamic validity were poor, and caution is recommended when measuring the absolute magnitude of acceleration, particularly for high-frequency movements. Regular assessment of individual devices is advised, particularly for mechanical damage and signal-drift errors. It is recommended that guidelines be provided by the manufacturer on measuring shifts in the base accelerometer signal, including time frames for assessing accelerometer axis, magnitude of errors, and calibration of accelerometers from a stable reference point.

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Kelly R. Rice, Catherine Gammon, Karin Pfieffer and Stewart Trost

Purpose:

The OMNI perceived exertion scale was developed for children to report perceived effort while performing physical activity; however no studies have formally examined age-related differences in validity. This study evaluated the validity of the OMNI-RPE in 4 age groups performing a range of lifestyle activities.

Methods:

206 participants were stratified into four age groups: 6-8 years (n = 42), 9-10 years (n = 46), 11-12 years (n = 47), and 13-15 years (n = 71). Heart rate and VO2 were measured during 11 activity trials ranging in intensity from sedentary to vigorous. After each trial, participants reported effort from the OMNI walk/run scale. Concurrent validity was assessed by calculating within-subject correlations between OMNI ratings and the two physiological indices.

Results:

The average correlation between OMNI ratings and VO2 was 0.67, 0.77, 0.85, and 0.87 for the 6-8, 9-10, 11-12 and 13-15 y age groups, respectively.

Conclusion:

The OMNI RPE scale demonstrated fair to good evidence of validity across a range of lifestyle activities among 6- to 15-year-old children. The validity of the scale appears to be developmentally related with RPE reports closely reflecting physiological responses among children older than 8 years.

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Barbara Resnick

Development of a reliable and valid measure of outcome expectations for exercise for older adults will help establish the relationship between outcome expectations and exercise and facilitate the development of interventions to increase physical activity in older adults. The purpose of this study was to test the reliability and validity of the Outcome Expectations for Exercise-2 Scale (OEE-2), a 13-item measure with two subscales: positive OEE (POEE) and negative OEE (NOEE). The OEE-2 scale was given to 161 residents in a continuing-care retirement community. There was some evidence of validity based on confirmatory factor analysis, Rasch-analysis INFIT and OUTFIT statistics, and convergent validity and test criterion relationships. There was some evidence for reliability of the OEE-2 based on alpha coefficients, person- and item-separation reliability indexes, and R 2 values. Based on analyses, suggested revisions are provided for future use of the OEE-2. Although ongoing reliability and validity testing are needed, the OEE-2 scale can be used to identify older adults with low outcome expectations for exercise, and interventions can then be implemented to strengthen these expectations and improve exercise behavior.

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Martyn Standage, Joan L. Duda, Darren C. Treasure and Keven A. Prusak

This research assessed the reliability, presence of a proposed simplex pattern (construct validity), factorial validity, and multisample invariance of the Situational Motivation Scale (SIMS; Guay, Vallerand, & Blanchard, 2000). In Study 1, data were collected from three physical activity samples. After establishing internal consistencies for all scales, bivariate and interfactor correlations were calculated and the results supported a simplex pattern across samples. The SIMS factorial validity across the three samples was tested via confirmatory factor analysis. Based on modification indices and theoretical justification, the SIMS was reduced to a 14-item model and the multisample invariance of this solution was examined. Results supported partial invariance. In Study 2, a total of 1,008 female PE students responded to the SIMS under two experimental conditions. Internal consistency and the assumed simplex pattern was again supported. Finally, the results of multisample CFA were consistent with the proposed post hoc model respecifications suggested in Study 1, supporting partial invariance.

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Marissa E. Mendelsohn, Denise M. Connelly, Tom J. Overend and Robert J. Petrella

Although popular in clinical settings, little is known about the utility of all-extremity semirecumbent exercise machines for research. Twenty-one community-dwelling older adults performed two exercise trials (three 4-min stages at increasing workloads) to evaluate the reliability and validity of exercise responses to submaximal all-extremity semirecumbent exercise (BioStep). Exercise responses were measured directly (Cosmed K4b2) and indirectly through software on the BioStep. Test–retest reliability (ICC2,1) was moderate to high across all three stages for directly measured METs (.92, .87, and .88) and HR (.91, .83, and .86). Concurrent criterion validity between the K4b2 and BioStep MET values was moderate to very good across the three stages on both Day 1 (r = .86, .71, and .83) and Day 2 (r = .73, .87, and .72). All-extremity semirecumbent submaximal exercise elicited reliable and valid responses in our sample of older adults and thus can be considered a viable exercise mode.

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Clive J. Brewer and Robyn L. Jones

The purpose of this paper is to propose a five-stage process for establishing both validity and reliability in new systematic observation instruments. The process is contextualized within the working behaviors of elite level rugby union coaches within the practice setting. The sequential stages began with observer training and progressed through the identification of coaching behaviors through induction (to establish content validity), to establishing face validity through a domain-referenced test. The objectivity and reliability of the developed behavioral classifications are determined through an interobserver agreement test while, finally, the researcher’s ability to reliably reproduce data with the developed instrument is determined using a test/retest intraobserver reliability check. The developed instrument (the Rugby Union Coaches Observation Instrument: RUCOI) is deemed able to record the situationally unique behaviors arising from the nature of the sport and of the elite standard, both of which were considered to impinge upon the pedagogical process in the said context.

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Kenny Guex, Chantal Daucourt and Stéphane Borloz

Context:

In the field of sport rehabilitation, an easy, valid, and reliable assessment of maximal strength is crucial for efficient muscle rehabilitation. Classically, it is performed on fitness equipment that is not necessary available in the field. Thera-Band has developed elastic bands with different resistances depending on the color of the band and on the percentage of its stretch. This may allow testing maximal strength.

Objective:

To determine validity and reliability of maximal-strength assessment of knee flexors and extensors using elastic bands.

Design:

Reliability and validity study.

Participants:

22 healthy participants (31.3 ± 7.0 y, 175.5 ± 8.5 cm, 70.7 ± 12.9 kg).

Intervention:

Participants performed 2 maximal-strength assessments, separated by 7 d, of the knee flexors and extensors using elastic bands. After the 2nd trial, a maximal concentric isokinetic test at 60°/s was performed.

Main Outcome Measures:

Correlations between 1-repetition maximum using elastic bands and peak torque on an isokinetic dynamometer were used to determine the validity of the proposed method, while ICC, CV, and SEM were used to determine reliability between the 1st and 2nd trials.

Results:

The validity of the proposed method was found to be very high (r = .93 for both knee flexors and extensors). The relative reliability was found to be very high (ICC = .98 and .99 for knee flexors and extensors, respectively), while absolute reliability was also very satisfying (CV = 3.44% and 2.33%; SEM = 1.70 and 2.16 kg for knee flexors and extensors, respectively).

Conclusions:

Thera-Band is a valid and reliable alternative to the use of fitness equipment to test maximal strength of the knee flexors and extensors in healthy subjects. The ease of use, accessibility, and low cost of elastic bands should allow regular assessment during the rehabilitation process.