Novel Use of the Nintendo Wii Board for Measuring Isometric Lower Limb Strength: A Reproducible and Valid Method in Older Adults

BackgroundPortable, low-cost, objective and reproducible assessment of muscle strength in the lower limbs is important as it allows clinicians to precisly track progression of patients undergoing rehabilitation. The Nintendo Wii Balance Board (WBB) is portable, inexpensive, durable, available worldwide, and may serve the above function.ObjectiveThe purpose of the study was to evaluate (1) reproducibility and (2) concurrent validity of the WBB for measuring isometric muscle strength in the lower limb.MethodsA custom hardware and software was developed to utilize the WBB for assessment of isometric muscle strength. Thirty older adults (69.0±4.2 years of age) were studied on two separate occasions on both the WBB and a stationary isometric dynamometer (SID). On each occasion, three recordings were obtained from each device. For the first recording, means and maximum values were used for further analysis. The test-retest reproducibility was examined using intraclass correlation coefficients (ICC), Standard Error of Measurement (SEM), and limits of agreement (LOA). Bland-Altman plots (BAP) and ICC’s were used to explore concurrent validity.ResultsNo systematic difference between test-retest was detected for the WBB. ICC within-device were between 0.90 and 0.96 and between-devices were from 0.80 to 0.84. SEM ranged for the WBB from 9.7 to 13.9%, and for the SID from 11.9 to 13.1%. LOA ranged for the WBB from 20.3 to 28.7% and for the SID from 24.2 to 26.6%. The BAP showed no relationship between the difference and the mean.ConclusionsA high relative and an acceptable absolute reproducibility combined with a good validity was found for the novel method using the WBB for measuring isometric lower limb strength in older adults. Further research using the WBB for assessing lower limb strength should be conducted in different study-populations.     

Reliability of EMG power-spectrum and amplitude of the semitendinosus and biceps femoris muscles during ramp isometric contractions

Appropriate reliability is a necessary condition for the use of surface EMG for evaluation of hamstring muscle function in cases of knee joint pathologies or ligament injuries. The aim of the study was to investigate the test-retest reliability of power spectrum and amplitude of surface electromyographic (EMG) measurements of semitendinosus (ST) and biceps femoris (BF) during ramp isometric contractions. Eleven males performed maximum isometric contractions (MVC) of the knee flexors in two sessions, a week apart with simultaneous recording of surface EMG of the BF and ST. Intra class correlation (ICC) and standard error measurements (SEM) were applied to assess test-retest reliability of the averaged EMG (aEMG) and the median frequency (MF) over 10 levels of force, from 0% to 100% of the maximum. The ICC values ranged from 0.38 to 0.96 for the aEMG with SEM values reaching 11.37% of MVC. For the MF, the ICCs ranged from 0.44 to 0.98 (SEM range 4.49–18.19 Hz). In our set up, ramp contractions can be used to examine hamstring EMG patterns with acceptable reliability.     

The validity and reliability of the 1RM bench press using chain-loaded resistance

The purposes of this study were to determine the validity and test-retest reliability of the 1 repetition maximum (1RM) chain-loaded, free-weight bench press (CBP) and to examine possible learning effects that may occur between the test-retest measurements. Nine resistance-trained men (20.58 +/- 1.31 years, 188.24 +/- 9.29 cm, 92.07 +/- 16.94 kg) and seven resistance-trained women (20.42 +/- 0.98 years, 175.61 +/- 9.32 cm, 73.61 +/- 10.80 kg) participating in Division II college basketball completed this study. Two familiarization sessions took place using light to moderate loads to learn proper technique. The subjects completed a 1RM test on the traditional plate-loaded bench press 4 days before completion of the CBP 1RM, which was followed by 4 days of rest before completing the retest. Intraclass correlation coefficients (ICC) and the percent coefficients of variation (CV) were used to determine relative and absolute test-retest reliability. Concurrent validity was determined from the Pearson correlation coefficients between the CBP and the plate-loaded bench press. Test-retest differences were analyzed with the paired t-test. ICC and CV for the men (r = 0.99, 1.4%) and women (r = 0.93, 3.5%), respectively indicate that highly reproducible 1RM scores can be found with the CBP. High validity was also found with high correlations between the CBP and plate-loaded bench press for the men (r = 0.95) and women (r = 0.80). A statistically significant (p = 0.04) but clinically small (2.57 kg) shift in the mean occurred between the CBP test and retest for the men, whereas no change occurred for the women. The data indicate that valid and reliable 1RM scores can be found after two familiarization sessions in men and women athletes who have previous resistance training experience.     

Familiarization and reliability of multiple sprint running performance indices

The aims of this study were to evaluate the time-course of the familiarization process associated with a test of multiple sprint running performance and to determine the reliability of various performance indices once familiarization had been established. Eleven physically active men (mean age: 21 +/- 2 years) completed 4 multiple sprint running trials (12 x 30 m; repeated at 35-s intervals) with 7 days between trials. All testing was conducted indoors, and times were recorded by twin-beam photocells. Results revealed no apparent learning effects as evidenced by no significant (p > 0.05) between-trial differences in measures of fastest or mean 30-m sprint time. Within-subject test-retest reliability determined over 4 trials by coefficient of variation (CV) and intraclass correlation coefficient (ICC) showed excellent reliability for measures of fastest and mean sprint times (CV range: 1.34-2.24%; ICC range: 0.79-0.94). Pre- and posttrial blood lactate concentrations showed good reliability when judged in context with typical values (CV range: 12.08-18.21%; ICC range: 0.72-0.78). In contrast, and in line with previous research, fatigue data showed much greater variability (CV: 26.43%; ICC: 0.66). The results of this study suggest that high degrees of test-retest reliability can be obtained in many multiple sprint running indices without the need for prior familiarization.     

Reproducibility and variation of morphometric analysis of carcinoembryonic antigen staining in histopathology. The influence of standardized microscopic fields

Using morphometric methods, five pathologists analyzed the positive staining for carcinoembryonic antigen (CEA) in sections from 17 ovarian tumors, with the intraclass correlation coefficient (ICC) and the mean values of the coefficients of variation (CV) used to assess reproducibility and variation. First, field and point scores for epithelium and mucin were estimated using 25 randomly selected square fields in sections from each of the tumors. The ICC range in the whole sample field was 0.53 to 0.81 (slight to substantial reproducibility) while the mean values of CV were 0.50 to 0.75. Second, the results of using random and standardized individual fields for the measurements were studied in three tumors. In random fields, the ICC was 0.57 to 0.71 (slight to moderate reproducibility) and the mean values of CV were 0.53 to 0.65. The corresponding values in standardized fields were 0.71 to 0.73 (moderate reproducibility) and 0.41 to 0.57, respectively. The results show that the variation is smaller and the degree of reproducibility higher in standardized fields. Considerable variation remains, however, revealing human factors as an important source of variation in practical morphometry.     

Quadriceps and hamstring isokinetic strength and electromyographic activity measured at different ranges of motion: a reproducibility study.

Isokinetic strength measurements of the quadriceps and hamstring that are commonly conducted using a 90 degrees range of motion (RoM) may involve some risk to specific knee patient groups. Testing these muscles at a much shorter RoM may reduce the risk but in order to render this method clinically acceptable the reproducibility of the derived test findings has to be established. Therefore the main objective of this study was to assess the reproducibility of isokinetic peak torque and normalized EMG scores of these muscles based on 90 degrees (0-90 degrees flexion, LR) and three successive short RoMs: 0-30 degrees (SR1), 30-60 degrees (SR2) and 60-90 degrees (SR3). Eight healthy subjects were tested three times with a 2 week between-session interval. All tests were performed on the dominant limb and consisted of maximal concentric and eccentric exertions. The velocities applied were 90 degrees /s for LR and 30 degrees /s for each of the SRs. Findings indicated no between-session improvement in strength. Based on the coefficient of variation the measurement error for all isokinetic strength scores remained stable throughout the testing sessions ranging 0.6-13.9% with the absolute majority of instances less than 10%. The reproducibility of the EMG scores was poorer ranging 1.5-25% and 0.5-19% for the quadriceps and hamstring, respectively. It is concluded that testing of knee muscles at short (30 degrees ) RoMs does not compromise the reproducibility of the strength or EMG scores derived from the commonly used RoM of 90 degrees . However, whereas strength was reproducible to within the accepted clinical standards, the corresponding EMG scores were characterized by a wider error band.     

Test-retest reliability of isometric mid-thigh pull maximum strength assessment: a systematic review

The aim of this systematic review was to explore the test-retest reliability of isometric mid-thigh pull maximum strength assessment. We searched through five databases to find studies that examined the test-retest reliability of peak force in the isometric mid-thigh pull exercise. From each included study, we extracted intra-class correlation coefficients (ICC) and/or coefficient of variation (CV). The methodological quality of the included studies was evaluated using the COSMIN checklist. A total of 16 good-to-excellent quality studies were included in the review. When considering results from all included studies, ICCs ranged from 0.73 to 0.99 (median ICC = 0.96), where 78% of ICCs were ≥ 0.90, and 98% of ICCs were ≥ 0.75. The range of reported CVs was from 0.7% to 11.1% (median CV = 4.9%), where 58% of CVs were ≤ 5%. Reliability was also good-to-excellent for both relative and absolute peak force and for both bilateral and unilateral isometric mid-thigh pull tests. The majority of studies did not find significant differences between testing sessions. It can be concluded that the isometric mid-thigh pull maximum strength assessment has good-to-excellent test-retest reliability. The isometric mid-thigh pull maximum strength assessment can be used as a reliable test in sports practice and for research purposes.     

Reliability and validity of the performance index evaluation among men's and women's college basketball players

The Performance Index Evaluation (PIE) is a basketball-specific assessment of physical performance. The battery consists of items typically included in sport assessments, such as agility and power, but also addresses an often-overlooked performance component, namely, core strength. The purpose of this study was to examine the reliability (test-retest, interrater), validity (criterion-related, construct-related), and practice effect of the PIE among men's and women's college basketball players. Test-retest estimates were moderate for men (intraclass correlation coefficient [ICC] = 0.79) and poor for women (ICC = 0.35), but interrater reliability was high (ICC = 0.95). Criterion-related validity evidence (i.e., relationship between PIE and playing time) was weak, but construct-related evidence was acceptable (i.e., college players had higher scores than high school players). A practice effect was also demonstrated among men. In conclusion, reliability of the battery should be improved before its use is recommended among college basketball players. Additionally, the battery does not appear to be a predictor of performance but does appear to distinguish between skill levels.     

Test–retest reliability of cardinal plane isokinetic hip torque and EMG

The objective of the present study was to establish test–retest reliability of isokinetic hip torque and prime mover electromyogram (EMG) through the three cardinal planes of motion. Thirteen healthy young adults participated in two experimental sessions, separated by approximately one week. During each session, isokinetic hip torque was evaluated on the Biodex Isokinetic Dynamometer at a velocity of 60 deg/s. Subjects performed three maximal-effort concentric and eccentric contractions, separately, for right and left hip abduction/adduction, flexion/extension, and internal/external rotation. Surface EMGs were sampled from the gluteus maximus, gluteus medius, adductor, medial and lateral hamstring, and rectus femoris muscles during all contractions. Intraclass correlation coefficients (ICC – 2,1) and standard errors of measurement (SEM) were calculated for peak torque for each movement direction and contraction mode, while ICCs were only computed for the EMG data. Motions that demonstrated high torque reliability included concentric hip abduction (right and left), flexion (right and left), extension (right) and internal rotation (right and left), and eccentric hip abduction (left), adduction (left), flexion (right), and extension (right and left) (ICC range = 0.81–0.91). Motions with moderate torque reliability included concentric hip adduction (right), extension (left), internal rotation (left), and external rotation (right), and eccentric hip abduction and adduction (right), flexion (left), internal rotation (right and left), and external rotation (right and left) (ICC range = 0.49–0.79). The majority of the EMG sampled muscles (n = 12 and n = 11 for concentric and eccentric contractions, respectively) demonstrated high reliability (ICC = 0.81–0.95). Instances of low, or unacceptable, EMG reliability values occurred for the medial hamstring muscle of the left leg (both contraction modes) and the adductor muscle of the right leg during eccentric internal rotation. The major finding revealed high and moderate levels of between-day reliability of isokinetic hip peak torque and prime mover EMG. It is recommended that the day-to-day variability estimates concomitant with acceptable levels of reliability be considered when attempting to objectify intervention effects on hip muscle performance.     

Reliability of concentric and eccentric strength of hip abductor and adductor muscles in young soccer players

The concentric and eccentric strength profile and muscular balance of the hip joint are important parameters for success in soccer. This study evaluated the reliability for the assessment of hip abduction and adduction isokinetic strength over a range of angular velocities (30 and 90°/s) and types of muscular actions (concentric and eccentric) in young soccer players. The reliability for the assessment of reciprocal (conventional and functional) and bilateral torque ratios was also examined. Fifteen male soccer players (15±1 years) performed two sessions, separated by three days. The testing protocol consisted of five maximal concentric and eccentric hip abductions and adductions of both legs at angular velocities of 30°/s and 90°/s. The peak torque was evaluated in young soccer players using an isokinetic dynamometer (Cybex Norm), and the reciprocal strength ratios (conventional and functional) and bilateral ratios (non-preferred to preferred leg ratios) were calculated. The test-retest reliability for the assessment of peak torque (ICC = 0.71-0.92) and of reciprocal muscle group ratios (ICC = 0.44-0.87) was found to be moderate to high. Bilateral torque ratios exhibited low to moderate reliability (ICC = 0.11-0.64). In conclusion, isokinetic strength of hip abductor and adductor muscles and the conventional and functional strength ratios can be reliably assessed in young soccer players, especially at low angular velocities. The assessment, however, of bilateral strength ratios for hip abductor/adductor muscles should be interpreted with more caution.     

Validity of hamstring muscle length assessment during the sit-and-reach test using an inclinometer to measure hip joint angle

The aim of this study was twofold: (i) to describe the criterion-related validity of the sit-and-reach test (SRT) using a hand-held inclinometer when assessing hamstring muscle length (HML) when HML is recorded in degrees of hip joint angle (HJA); and (ii) to describe the effect of gender and age on HML in healthy adults during the performance of a SRT. We examined 212 healthy subjects (106 men and 106 women) whose ages ranged from 20 to 79 years. The Pearson-product moment correlation coefficient (r) described the relationship between HJA at the end-point of the SRT and the criterion, supine passive straight-leg raise (PSLR). We conducted a 6 x 2 analysis of variance, where age was stratified on 6 levels of 10-year increments (20-29, 30-39, 40-49, 50-59, 60-69, and 70-79 years of age) and gender was stratified on 2 levels (men and women). There was a statistically significant correlation (r = 0.59, P < 0.01) between performance on the SRT as measured by HJA and the supine PSLR, but the SRT only accounted for 35% of the variability in the PSLR. SRT performance in men (mean +/- SD, 80 +/- 9 degrees) was significantly less (P < 0.001) than in women (mean +/- SD, 92 +/- 10 degrees). Subjects in the 60- to 69- and 70- to 79-year age groups had significantly less (P < 0.05) HJA than those in the 20- to 29-, 30- to 39-, and 40- to 49-year age groups. Using an inclinometer to measure HJA during the SRT is not a valid method for assessing HML in men and women who can independently assume a long-sitting position on a hard surface. Clinicians should recognize there are differences in HML between men and women, and that men and women between 20 to 49 years of age have more HML than their counterparts between ages 60 to 79 years.     

Test-retest reliability, criterion-related validity, and minimal detectable change of score on an abbreviated Wingate test for field sport participants

Repeat measurements in 69 young adults were performed to assess the test-retest reliability and the 95% confidence interval of the difference in score between paired observations (MDC95) of a Wingate test as abbreviated for field sport participants (test of a 15-second duration [15-secT]). Test-retest reliability was excellent for peak power output (PPO) and mean power output (MPO), independently of their mode of expression and was moderate for the fatigue index (FI). The standard errors of measurement (SEM) for absolute, relative, and derived PPO and MPO values ranged from 2.6 to 3.7%, all being smaller than the corresponding smallest worthwhile change (SWC). In contrast, FI values were rated as "marginal," with an SEM (9.6%) greater than the SWC (1.7). The range of MDC95 values for PPO and MPO were 9.9-10.4 and 7.37-7.42%, respectively. The absolute MPO showed the highest test-retest reliability and was the most effective in detecting real change. A second phase of the study evaluated the criterion-related validity of the 15-secT in 43 young men who performed 15-secT and standard 30-second Wingate anaerobic test (30-secT) in random order, on 2 separate occasions. There were no significant intertest differences in absolute, relative, or derived PPO. However, the FI for the 30-secT was greater than that for the 15-secT. Intertest correlations were highly significant for both MPOs and FIs. These findings suggest that the abbreviated Wingate test offers a reliable and valid tool for the evaluation of PPO and MPO, at least in young physical education students.     

The reliability of three devices used for measuring vertical jump height

The purpose of this investigation was to assess the intrasession and intersession reliability of the Vertec, Just Jump System, and Myotest for measuring countermovement vertical jump (CMJ) height. Forty male and 39 female university students completed 3 maximal-effort CMJs during 2 testing sessions, which were separated by 24-48 hours. The height of the CMJ was measured from all 3 devices simultaneously. Systematic error, relative reliability, absolute reliability, and heteroscedasticity were assessed for each device. Systematic error across the 3 CMJ trials was observed within both sessions for males and females, and this was most frequently observed when the CMJ height was measured by the Vertec. No systematic error was discovered across the 2 testing sessions when the maximum CMJ heights from the 2 sessions were compared. In males, the Myotest demonstrated the best intrasession reliability (intraclass correlation coefficient [ICC] = 0.95; SEM = 1.5 cm; coefficient of variation [CV] = 3.3%) and intersession reliability (ICC = 0.88; SEM = 2.4 cm; CV = 5.3%; limits of agreement = -0.08 ± 4.06 cm). Similarly, in females, the Myotest demonstrated the best intrasession reliability (ICC = 0.91; SEM = 1.4 cm; CV = 4.5%) and intersession reliability (ICC = 0.92; SEM = 1.3 cm; CV = 4.1%; limits of agreement = 0.33 ± 3.53 cm). Additional analysis revealed that heteroscedasticity was present in the CMJ when measured from all 3 devices, indicating that better jumpers demonstrate greater fluctuations in CMJ scores across testing sessions. To attain reliable CMJ height measurements, practitioners are encouraged to familiarize athletes with the CMJ technique and then allow the athletes to complete numerous repetitions until performance plateaus, particularly if the Vertec is being used.     

Critical power can be estimated from nonexhaustive tests based on rating of perceived exertion responses

The purpose of this study was to evaluate a novel procedure, based on the perceived exertion threshold (PET) concept, involving non-exhaustive tests (PET14-17) to estimate critical power (CP), as well as to examine the reproducibility of these indices. Twenty young men performed 2 trials (Trial 1 and Trial 2) of 4 exhaustive predictive tests to estimate CP, PET, and PET14-17. The slope coefficients of the regression lines corresponding to the ratings of perceived exertion (RPE) versus time relationship (y axis) obtained during the predictive tests were plotted against the power outputs (x axis) to estimate PET. PET was calculated as the intersection point of the regression line in the power axis. The 14-17 RPE range of each predictive test was modeled using the same mathematical procedures used to estimate PET14-17. CP was derived from the power-time hyperbolic equation. Analysis of variance revealed no significant differences among CP (189-194 W), PET (190-191 W) and PET14-17, (191-195 W). The correlations between CP and PET (r = 0.87), CP and PET14-17 (r = 0.89), and PET and PET14-17 (r = 0.88) were all strong. Additionally, the bias +/- limits of agreement when plotting CP and PET was -2.16 +/- 31.60 W, and -5.70 +/- 31.21 W when comparing CP and PET14-17. Relatively high reproducibility levels of CP (ICC = 0.96), PET (ICC = 0.85) and PET14-17 (ICC = 0.83) were recorded in the test-retest fashion. It can be concluded that the PET14-17 can be utilized with relatively high accuracy and reproducibility to estimate CP without causing exhaustion in the subjects.     

Cerebral Blood Volume Analysis in Glioblastomas Using Dynamic Susceptibility Contrast-Enhanced Perfusion MRI: A Comparison of Manual and Semiautomatic Segmentation Methods

Purpose

To compare the reproducibilities of manual and semiautomatic segmentation method for the measurement of normalized cerebral blood volume (nCBV) using dynamic susceptibility contrast-enhanced (DSC) perfusion MR imaging in glioblastomas.

Materials and Methods

Twenty-two patients (11 male, 11 female; 27 tumors) with histologically confirmed glioblastoma (WHO grade IV) were examined with conventional MR imaging and DSC imaging at 3T before surgery or biopsy. Then nCBV (means and standard deviations) in each mass was measured using two DSC MR perfusion analysis methods including manual and semiautomatic segmentation method, in which contrast-enhanced (CE)-T1WI and T2WI were used as structural imaging. Intraobserver and interobserver reproducibility were assessed according to each perfusion analysis method or each structural imaging. Interclass correlation coefficient (ICC), Bland-Altman plot, and coefficient of variation (CV) were used to evaluate reproducibility.

Results

Intraobserver reproducibilities on CE-T1WI and T2WI were ICC of 0.74–0.89 and CV of 20.39–36.83% in manual segmentation method, and ICC of 0.95–0.99 and CV of 8.53–16.19% in semiautomatic segmentation method, repectively. Interobserver reproducibilites on CE-T1WI and T2WI were ICC of 0.86–0.94 and CV of 19.67–35.15% in manual segmentation method, and ICC of 0.74–1.0 and CV of 5.48–49.38% in semiautomatic segmentation method, respectively. Bland-Altman plots showed a good correlation with ICC or CV in each method. The semiautomatic segmentation method showed higher intraobserver and interobserver reproducibilities at CE-T1WI-based study than other methods.

Conclusion

The best reproducibility was found using the semiautomatic segmentation method based on CE-T1WI for structural imaging in the measurement of the nCBV of glioblastomas.     

Test-retest reliability of three different countermovement jumping tests

In studies of physical performance comprising muscle strength and power, a vertical jump is a test method that frequently is used. It is important to have access to accurate measuring tools providing data with high reproducibility. Studies have shown that body composition also may play an important part in physical performance. The purpose of this study was to determine test-retest reliability for 3 different kinds of vertical jumps and to correlate jump height with body composition. Thirty-four normally trained subjects (women n = 17) between 18 and 25 years participated. Test-retest, on 3 kinds of vertical jumps, was performed with a median of 7 days between jumps. Methods used were a countermovement jump (CMJ) on a contact mat, with and without arm swing, and an Abalakow jump (AJ) using measuring tape, with arm swing. Body composition was assessed with the use of bioelectric impedance analysis. The results showed that high intraclass correlation coefficients (ICCs) were observed between testing occasions for all 3 vertical jumps (ICC between 0.48 and 0.88). The AJ in women presented the lowest ICC. Also the correlation between CMJ and AJ was high (rs = 0.88). Moderate-to-high correlations could be shown between body composition and CMJ in women (rs = -0.57-0.76). In conclusion, very high test-retest reliability for CMJ on a contact mat was found. For the AJ using a measuring tape, ICC were overall high, but a moderate nonsignificant ICC were found in women, indicating poor reproducibility. The data from the CMJ and AJ may be compared if approximately 25% of the AJ value is subtracted. In practice, this means that vertical jump tests have high reproducibility and can be used as measures of power development.     

Between-day reliability of a method for non-invasive estimation of muscle composition

Tensiomyography is a method for valid and non-invasive estimation of skeletal muscle fibre type composition. The validity of selected temporal tensiomyographic measures has been well established recently; there is, however, no evidence regarding the method's between-day reliability. Therefore it is the aim of this paper to establish the between-day repeatability of tensiomyographic measures in three skeletal muscles. For three consecutive days, 10 healthy male volunteers (mean±SD: age 24.6 ± 3.0 years; height 177.9 ± 3.9 cm; weight 72.4 ± 5.2 kg) were examined in a supine position. Four temporal measures (delay, contraction, sustain, and half-relaxation time) and maximal amplitude were extracted from the displacement-time tensiomyogram. A reliability analysis was performed with calculations of bias, random error, coefficient of variation (CV), standard error of measurement, and intra-class correlation coefficient (ICC) with a 95% confidence interval. An analysis of ICC demonstrated excellent agreement (ICC were over 0.94 in 14 out of 15 tested parameters). However, lower CV was observed in half-relaxation time, presumably because of the specifics of the parameter definition itself. These data indicate that for the three muscles tested, tensiomyographic measurements were reproducible across consecutive test days. Furthermore, we indicated the most possible origin of the lowest reliability detected in half-relaxation time.     

Differences of Intrasession Reproducibility of Circumpapillary Total Retinal Thickness and Circumpapillary Retinal Nerve Fiber Layer Thickness Measurements Made with the RS-3000 Optical Coherence Tomograph

Purpose

To evaluate the intrasession reproducibility of various thickness parameters used to diagnose and follow-up glaucoma, in particular circumpapillary total retinal thickness (cpTR) provided by the RS-3000 optical coherence tomograph (OCT).

Methods

Fifty-three healthy eyes of 28 subjects underwent three consecutive imaging with the RS-3000 Advance OCT (NIDEK, Aichi,Japan) to evaluate the intrasession reproducibility of circumpapillary total retinal thickness (cpTR), circumpapillary retinal nerve fiber layer thickness (cpRNFL), macular ganglion cell complex thickness (mGCC) and macular total retina thickness (mTR) measurements. Intraclass correlation (ICC), coefficient of variation (CV) and reproducibility coefficient (RC) were calculated for each parameter.

Results

The ICC and CV values for mean cpTR and cpRNFL were 0.987 and 0.897, and 0.60% and 2.81%, respectively. The RC values for the mean cpTR and cpRNFL were 5.95 μm and 9.04 μm, respectively. For all cpTR parameters the ICC values were higher and both the CV and RC values were lower than those for the corresponding cpRNFL parameters. The ICC and CV values for superior mGCC, inferior mGCC, superior mTR and inferior mTR were 0.983, 0.980, 0.983 and 0.988, and 0.84%, 0.98%, 0.48% and 0.43%, respectively. The RC values for superior mGCC, inferior mGCC, superior mTR and inferior mTR were 2.86 μm, 3.12 μm, 4.41μm and 4.43 μm, respectively.

Conclusions

Intrasession reproducibility of cpTR, mGCC and mTR measurements made on healthy eyes was high. Repeatability of cpTR measurements was better than that of the corresponding cpRNFL measurements. These results suggest that future clinical investigations addressing detection of glaucoma and glaucomatous progression with the RS-3000 OCT may benefit from focusing on the cpTR parameters.     

The Mini-BESTest - a clinically reproducible tool for balance evaluations in mild to moderate Parkinson’s disease?

Background

The Mini-BESTest is a clinical balance test that has shown a high sensitivity in detecting balance impairments in elderly with Parkinson's disease (PD). However, its reproducibility between different raters and between test occasions has yet to be investigated in a clinical context. Moreover, no one has investigated the reproducibility of the Mini-BESTest's subcomponents (i.e. anticipatory postural adjustments; postural responses; sensory orientation and dynamic gait).We aimed to investigate the inter-rater and test-retest reproducibility (reliability as well as agreement) of the Mini-BESTest, as well as its subcomponents, in elderly with mild to moderate PD, performed under conditions assimilating clinical practice.

Method

This was an observational measurement study with a test-retest design.Twenty-seven individuals with idiopathic PD (66 - 80 years, mean age: 73; Hoehn & Yahr: 2-3; 1-15 years since diagnosis) were included. Two test administrators, having different experiences with the Mini-BESTest, administered the test individually, in separate rooms in a hospital setting. For the test-retest assessment, all participants returned 7 days after the first test session to perform the Mini-BESTest under similar conditions. Intra-class correlation coefficients (ICC_2.1), standard error of measurement (SEM_agreement), and smallest real difference (SRD) were analyzed.

Results

The Mini-BESTest showed good reliability for both inter-rater and test-retest reproducibility (ICC = 0.72 and 0.80). Regarding agreement, the measurement error (SRD) was found to be 4.1 points (accounting for 15% of the maximal total score) for inter-rater reproducibility and 3.4 points (12% of the maximal total score) for test-retest reproducibility. The investigation of the Mini-BESTest's subcomponents showed a similar pattern for both inter-rater and test-retest reproducibility, where postural responses had the largest proportional measurement error, and sensory orientation showed the highest agreement.

Conclusions

Our findings indicate that the Mini-BESTest is able to distinguish between individuals with mild to moderate PD; however, when used in clinical balance assessments, the large measurement error needs to be accounted for.

     

The seated medicine ball throw as a test of upper body power in older adults

Practitioners training the older adult may benefit from a low-cost, easy-to-administer field test of upper body power. This study evaluated validity and reliability of the seated medicine ball throw (SMBT) in older adults. Subjects (n = 33; age 72.4 ± 5.2 years) completed 6 trials of an SMBT in each of 2 testing days and 2 ball masses (1.5 and 3.0 kg). Subjects also completed 6 trials of an explosive push-up (EPU) on a force plate over 2 testing days. Validity was assessed via a Pearson Product-Moment correlation (PPM) between SMBT and EPU maximal vertical force. Reliability of the SMBT was determined using PPMs (r), Intraclass correlation (ICC, R) and Bland-Altman plots (BAPs). For validity, the association between the SMBT and the EPU revealed a PPM of r = 0.641 and r = 0.614 for the 1.5- and 3.0-kg medicine balls, respectively. Test-retest reliability of the 1.5- and 3.0-kg SMBT was r = 0.967 and r = 0.958, respectively. The ICC values of the 1.5- and 3.0-kg SMBT were R = 0.994 and 0.989, respectively. The BAPs revealed 94% of the differences between day 1 and 2 scores were within the 95% confidence interval of the mean difference. Test-retest reliability for the EPU was r = 0.944, R = 0.969. The BAPs showed 94% of the differences between day 1 and 2 scores were within the 95% confidence interval of the mean difference, for both medicine ball throws. In conclusion, for the older adult, the SMBT appears to be highly reliable test of upper body power. Its validity relative to the maximal force exerted during the EPU is modest. The SMBT is an inexpensive, safe, and repeatable measure of upper body power for the older adult.