Retest Reliability Of Measures Research Articles

Reliability of Lower Extremity Muscle Power and Functional Performance in Healthy, Older Women.

Evaluation of the long-term reliability of muscle power and functional performance tests in older, healthy adults is warranted since determining whether performance is consistent over longer durations is more relevant for intervention studies. Objective. To assess the long-term test–retest reliability of measures of muscle power and lower body functional performance in healthy, nonexercising, older women. Methods. Data were derived from a nonexercising control group (n = 18; age = 73.3 (3.4) years; height = 159.6 (7.7) cm; body mass = 69.5 (12.7) kg; BMI = 27.3 (4.8)) of a randomized controlled trial of muscle power training in older women. Participants underwent lower extremity muscle power (Biodex) and functional testing (Short Physical Performance Battery, gait speed, 30-second chair stands, stair climbing, and 400-meter walk) at week 0 (baseline), 9, and 15. Results. For the upper leg, intraclass correlation coefficients (ICCs) were very high for knee extension power (0.90–0.97) and high to very high for knee flexion power (0.83–0.96). For lower-leg power, ICCs were high to very high for plantar flexion and dorsiflexion (0.83–0.96). ICCs for functional performance were moderate to very high (0.64–0.93). Coefficient of variation of the typical error (CVTE) was <10.5% for knee extension/flexion power, 9.9–20.0% for plantar flexion/dorsiflexion power, and 1.9–14.9% for functional performance. Knee extension power and stair climb power demonstrated the highest reliability for muscle power and function, respectively. Mean values did not change over time, with the exception of the chair stands (p < 0.05); however, these changes were not considered clinically meaningful. Conclusions. The current study provides evidence supporting the long-term reliability of performance assessments of muscle power and lower body functional capacity over a period of up to 15 weeks in healthy, older women.

Kinematic and kinetic variability associated with the cable put and seated rotation assessments

ABSTRACT When new protocols are developed, there is a requirement to investigate test–retest reliability of measures for valid use and interpretation of data in research and practice. Therefore, the aim of this investigation was to determine the inter-day reliability of the cable put and seated rotation assessment protocols. On three occasions, nine resistance-trained men performed cable puts and cable rotations at different loads between 6 and 42 kg on a commercially available cable cross over machine. Load stack movement was recorded using a PT5A linear position transducer from which all kinematic and kinetic variables were calculated. Reliability was excellent for peak velocity and displacement based on intraclass correlation coefficient (ICC) and coefficient of variation (CV) across the majority of loads and movements (cable put: ICC = 0.92 to 0.99, CV = 3.1% to 8.6%; cable seated rotation: ICC = 0.76 to 0.99, CV = −1.7% to 16.1%). However, kinetic variables demonstrated inadequate reliability across the majority of days, loads and movements (ICC = 0.70, CV >10%). It was concluded that peak velocity is a reliable kinematic measure to assess muscular capability from cable put and seated rotation protocols; however, kinetic measures are too variable to provide reliable outputs across testing occasions.

Test–retest reliability of frontal alpha electroencephalogram (EEG) and electrocardiogram (ECG) measures in adolescents: a pilot study

A number of studies have shown that the pattern of resting frontal EEG alpha power and asymmetry and heart rate are predictive of individual differences in affective style in children and adults. Although test–retest reliability of frontal electrocortical and autonomic measures has been established in adult and child and some clinical populations, few studies have examined test–retest reliability of these measures in adolescents. Here, we conducted a pilot study to examine the test–retest reliability of frontal EEG alpha power and asymmetry and heart period and heart rate in 10 typically developing adolescent participants (M age = 15.9 years) over a 1 month period. We found acceptable test–retest reliability using Pearson and intra-class correlations in left and right mid-frontal alpha power and asymmetry and heart period and heart rate over 1 month. These results provide initial evidence for acceptable levels of test-retest reliability in central and peripheral psychophysiological measures in adolescents used to index affective style in children and adults. Future studies are needed with a larger sample to ensure the reliability of these results.

Knee muscle strength – A challenge to measure

The aims were to assess the reliability of knee extensor and flexor muscle strength measurements using the Strength Measuring Chair (SMC) in children and adults, and to assess agreement between the SMC and an isokinetic dynamometer (ID). 20 healthy children (10/10 boys/girls, 5–13 years) and 23 adults (10/13 men/women, 23–60 years) were included. Muscle strength tests were performed in the SMC and in the ID. The intra-subject reliability was shown to be excellent in both instruments (ICC 0.93–0.99) and an excellent test–retest reliability of measurements in the SMC was found (ICC 0.87–0.93). Agreement between instruments was evaluated with ICC, paired t-test and Bland–Altman 95% limits of agreement plots. In both adults’ and children's groups, disagreements were found between the two instruments, with more in the children's group. The SMC, which has previously shown to be valid and reliable for measuring plantarflexor muscle strength, reliably measured knee muscle strength in healthy children and adults. However, the large disagreement found between the instruments, especially in the children's group, warrants care in standardizing measuring positions for different body size and warrants caution in comparing one's muscle strength measured using different assessment methods.

Retest Reliability of Centre of Pressure Measures of Standing Balance in Healthy Older Women

Centre of pressure (COP) measurements have been frequently used in the evaluation of postural control, especially in the elderly. Despite this, the retest reliability of these measures has not been well investigated in this age group. This study investigated the retest reliability of COP measures using a force platform in 17 women with a mean age of 69.5 years. Results indicated low correlations between test occasions for static stance postures with Intra class Correlation Coefficients (ICCs) ranging between 0.27 and 0.55. In contrast, ICCs were high (between 0.81 and 0.92) for test conditions involving angular perturbation of the support surface. Investigation of test durations of 10 and 25 second length did not indicate any significant difference between these two test durations (p&gt;0.05). The study also revealed no series effects using twelve consecutive 25 second tests on the force platform. These results support further investigation of dynamic standing balance in older women using the test protocol described in this study, including whether these tests are able to discriminate between fallers and non fallen, and their predictive validity.