Interobserver and test-retest reproducibility of T1ρ and T2 mesurements of lumber intervertebral discs by 3t magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Yoo, Yeon Hwa; Yoon, Choon Sik; Eun, Na Lae; Kim, Sung Jin; Chung, Tae Sub [Dept. of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Hwang, Moon Jung [GE Health Care, Seoul (Korea, Republic of); Yoo, Hanna [Biostatistics Collaboration Lab, Yonsei University College of Medicine, Seoul (Korea, Republic of); Peter, Robert D. [GE Health Care, Milwaukee (United States); Lee, Young Han; Suh, Jin Suck [Dept. of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

2016-11-15

To investigate the interobserver and test-retest reproducibility of T1ρ and T2 measurements of lumbar intervertebral discs using 3T magnetic resonance imaging (MRI). This study included a total of 51 volunteers (female, 26; male, 25; mean age, 54 ± 16.3 years) who underwent lumbar spine MRI with a 3.0 T scanner. Amongst these subjects, 40 underwent repeat T1ρ and T2 measurement acquisitions with identical image protocol. Two observers independently performed the region of interest measurements in the nuclei pulposi of the discs from L1-2 through L5-S1 levels. Statistical analysis was performed using intraclass correlation coefficient (ICC) with a two-way random model of absolute agreement. Comparison of the ICC values was done after acquisition of ICC values using Z test. Statistical significance was defined as p value < 0.05. The ICCs of interobserver reproducibility were 0.951 and 0.672 for T1ρ and T2 mapping, respectively. The ICCs of test-retest reproducibility (40 subjects) for T1ρ and T2 measurements were 0.922 and 0.617 for observer A and 0.914 and 0.628 for observer B, respectively. In the comparison of the aforementioned ICCs, ICCs of interobserver and test-retest reproducibility for T1ρ mapping were significantly higher than T2 mapping (p < 0.001). The interobserver and test-retest reproducibility of T1ρ mapping were significantly higher than those of T2 mapping for the quantitative assessment of nuclei pulposi of lumbar intervertebral discs.

Reproducibility of automated simplified voxel-based analysis of PET amyloid ligand [11C]PIB uptake using 30-min scanning data

International Nuclear Information System (INIS)

Aalto, Sargo; Scheinin, Noora M.; Naagren, Kjell; Rinne, Juha O.; Kemppainen, Nina M.; Kailajaervi, Marita; Leinonen, Mika; Scheinin, Mika

2009-01-01

Positron emission tomography (PET) with 11 C-labelled Pittsburgh compound B ([ 11 C]PIB) enables the quantitation of β-amyloid accumulation in the brain of patients with Alzheimer's disease (AD). Voxel-based image analysis techniques conducted in a standard brain space provide an objective, rapid and fully automated method to analyze [ 11 C]PIB PET data. The purpose of this study was to evaluate both region- and voxel-level reproducibility of automated and simplified [ 11 C]PIB quantitation when using only 30 min of imaging data. Six AD patients and four healthy controls were scanned twice with an average interval of 6 weeks. To evaluate the feasibility of short scanning (convenient for AD patients), [ 11 C]PIB uptake was quantitated using 30 min of imaging data (60 to 90 min after tracer injection) for region-to-cerebellum ratio calculations. To evaluate the reproducibility, a test-retest design was used to derive absolute variability (VAR) estimates and intraclass correlation coefficients at both region-of-interest (ROI) and voxel level. The reproducibility both at the region level (VAR 0.9-5.5%) and at the voxel level (VAR 4.2-6.4%) was good to excellent. Based on the variability estimates obtained, power calculations indicated that 90% power to obtain statistically significant difference can be achieved using a sample size of five subjects per group when a 15% change from baseline (increase or decrease) in [ 11 C]PIB accumulation in the frontal cortex is anticipated in one group compared to no change in another group. Our results showed that an automated analysis method based on an efficient scanning protocol provides reproducible results for [ 11 C]PIB uptake and appears suitable for PET studies aiming at the quantitation of amyloid accumulation in the brain of AD patients for the evaluation of progression and treatment effects. (orig.)

Test-retest reliability of the novel 5-HT1B receptor PET radioligand [11C]P943

International Nuclear Information System (INIS)

Saricicek, Aybala; Chen, Jason; Ruf, Barbara; Planeta, Beata; Labaree, David; Gallezot, Jean-Dominique; Huang, Yiyun; Subramanyam, Kalyani; Maloney, Kathleen; Matuskey, David; Deserno, Lorenz; Neumeister, Alexander; Krystal, John H.; Carson, Richard E.; Bhagwagar, Zubin

2015-01-01

[ 11 C]P943 is a novel, highly selective 5-HT 1B PET radioligand. The aim of this study was to determine the test-retest reliability of [ 11 C]P943 using two different modeling methods and to perform a power analysis with each quantification technique. Seven healthy volunteers underwent two PET scans on the same day. Regions of interest (ROIs) were the amygdala, hippocampus, pallidum, putamen, insula, frontal, anterior cingulate, parietal, temporal and occipital cortices, and cerebellum. Two multilinear radioligand quantification techniques were used to estimate binding potential: MA1, using arterial input function data, and the second version of the multilinear reference tissue model analysis (MRTM2), using the cerebellum as the reference region. Between-scan percent variability and intraclass correlation coefficients (ICC) were used to assess test-retest reliability. We also performed power analyses to determine the method that would allow the least number of subjects using within-subject or between-subject study designs. A voxel-wise ICC analysis for MRTM2 BP ND was performed for the whole brain and all the ROIs studied. Mean percent variability between two scans across regions ranged between 0.4 % and 12.4 % for MA1 BP ND , 0.5 % and 11.5 % for MA1 BP P , 16.7 % and 28.3 % for MA1 BP F , and between 0.2 % and 5.4 % for MRTM2 BP ND . The power analyses showed a greater number of subjects were required using MA1 BP F compared with other outcome measures for both within-subject and between-subject study designs. ICC values were the highest using MRTM2 BP ND and the lowest with MA1 BP F in ten ROIs. Small regions and regions with low binding had lower ICC values than large regions and regions with high binding. Reliable measures of 5-HT 1B receptor binding can be obtained using the novel PET radioligand [ 11 C]P943. Quantification of 5-HT 1B receptor binding with MRTM2 BP ND and with MA1 BP P provided the least variability and optimal power for within-subject and

Test-retest reproducibility of the metabotropic glutamate receptor 5 ligand [18F]FPEB with bolus plus constant infusion in humans

International Nuclear Information System (INIS)

Park, Eunkyung; Sullivan, Jenna M.; Planeta, Beata; Gallezot, Jean-Dominique; Lim, Keunpoong; Lin, Shu-Fei; Ropchan, Jim; Huang, Yiyun; Carson, Richard E.; McCarthy, Timothy J.; Ding, Yu-Shin; Morris, Evan D.; Williams, Wendol A.

2015-01-01

[ 18 F]FPEB is a promising PET radioligand for the metabotropic glutamate receptor 5 (mGluR5), a potential target for the treatment of neuropsychiatric diseases. The purpose of this study was to evaluate the test-retest reproducibility of [ 18 F]FPEB in the human brain. Seven healthy male subjects were scanned twice, 3 - 11 weeks apart. Dynamic data were acquired using bolus plus infusion of 162 ± 32 MBq [ 18 F]FPEB. Four methods were used to estimate volume of distribution (V T ): equilibrium analysis (EQ) using arterial (EQ A ) or venous input data (EQ V ), MA1, and a two-tissue compartment model (2 T). Binding potential (BP ND ) was also estimated using cerebellar white matter (CWM) or gray matter (CGM) as the reference region using EQ, 2 T and MA1. Absolute test-retest variability (aTRV) of V T and BP ND were calculated for each method. Venous blood measurements (C V ) were compared with arterial input (C A ) to examine their usability in EQ analysis. Regional V T estimated by the four methods displayed a high degree of agreement (r 2 ranging from 0.83 to 0.99 among the methods), although EQ A and EQ V overestimated V T by a mean of 9 % and 7 %, respectively, compared to 2 T. Mean values of aTRV of V T were 11 % by EQ A , 12 % by EQ V , 14 % by MA1 and 14 % by 2 T. Regional BP ND also agreed well among the methods and mean aTRV of BP ND was 8 - 12 % (CWM) and 7 - 9 % (CGM). Venous and arterial blood concentrations of [ 18 F]FPEB were well matched during equilibrium (C V = 1.01 . C A , r 2 = 0.95). [ 18 F]FPEB binding shows good TRV with minor differences among analysis methods. Venous blood can be used as an alternative for input function measurement instead of arterial blood in EQ analysis. Thus, [ 18 F]FPEB is an excellent PET imaging tracer for mGluR5 in humans. (orig.)

Test-retest reliability of {sup 11}C-ORM-13070 in PET imaging of α{sub 2C}-adrenoceptors in vivo in the human brain

Energy Technology Data Exchange (ETDEWEB)

Lehto, Jussi; Peltonen, Juha M.; Volanen, Iina; Scheinin, Mika [University of Turku, Clinical Research Services Turku CRST, Turku (Finland); TYKSLAB, Unit of Clinical Pharmacology, Turku (Finland); Virta, Jere R. [University of Turku and Turku University Hospital, Turku PET Centre, Turku (Finland); Turku University Hospital, Division of Clinical Neurosciences, Turku (Finland); Oikonen, Vesa; Roivainen, Anne; Luoto, Pauliina; Arponen, Eveliina; Helin, Semi; Virtanen, Kirsi [University of Turku and Turku University Hospital, Turku PET Centre, Turku (Finland); Hietamaeki, Johanna; Holopainen, Aila; Rouru, Juha; Sallinen, Jukka [Orion Pharma, Turku (Finland); Kailajaervi, Marita [Turku Imanet, GE Healthcare, Turku (Finland); Rinne, Juha O. [University of Turku and Turku University Hospital, Turku PET Centre, Turku (Finland); Turku University Hospital, Division of Clinical Neurosciences, Turku (Finland); University of Turku, Clinical Research Services Turku CRST, Turku (Finland)

2015-01-15

α{sub 2C}-Adrenoceptors share inhibitory presynaptic functions with the more abundant α{sub 2A}-adrenoceptor subtype, but they also have widespread postsynaptic modulatory functions in the brain. Research on the noradrenergic system of the human brain has been hampered by the lack of suitable PET tracers targeted to the α{sub 2}-adrenoceptor subtypes. PET imaging with the specific α{sub 2C}-adrenoceptor antagonist tracer [{sup 11}C]ORM-13070 was performed twice in six healthy male subjects to investigate the test-retest reliability of tracer binding. The bound/free ratio of tracer uptake relative to nonspecific uptake into the cerebellum during the time interval of 5 - 30 min was most prominent in the dorsal striatum: 0.77 in the putamen and 0.58 in the caudate nucleus. Absolute test-retest variability in bound/free ratios of tracer ranged from 4.3 % in the putamen to 29 % in the hippocampus. Variability was also <10 % in the caudate nucleus and thalamus. Intraclass correlation coefficients (ICC) ranged from 0.50 in the hippocampus to 0.89 in the thalamus (ICC >0.70 was also reached in the caudate nucleus, putamen, lateral frontal cortex and parietal cortex). The pattern of [{sup 11}C]ORM-13070 binding, as determined by PET, was in good agreement with receptor density results previously derived from post-mortem autoradiography. PET data analysis results obtained with a compartmental model fit, the simplified reference tissue model and a graphical reference tissue analysis method were convergent with the tissue ratio method. The results of this study support the use of [{sup 11}C]ORM-13070 PET in the quantitative assessment of α{sub 2C}-adrenoceptors in the human brain in vivo. Reliable assessment of specific tracer binding in the dorsal striatum is possible with the help of reference tissue ratios. (orig.)

Test-retest reliability of the novel 5-HT{sub 1B} receptor PET radioligand [{sup 11}C]P943

Energy Technology Data Exchange (ETDEWEB)

Saricicek, Aybala [Yale University, Department of Psychiatry, New Haven, CT (United States); Connecticut Mental Health Center, Abraham Ribicoff Research Facilities, New Haven, CT (United States); Izmir Katip Celebi University, Department of Psychiatry, Izmir (Turkey); Chen, Jason; Ruf, Barbara [Yale University, Department of Psychiatry, New Haven, CT (United States); Planeta, Beata; Labaree, David; Gallezot, Jean-Dominique; Huang, Yiyun [Yale University, PET Center, Department of Diagnostic Radiology, New Haven, CT (United States); Subramanyam, Kalyani; Maloney, Kathleen [Yale University, Department of Psychiatry, New Haven, CT (United States); Connecticut Mental Health Center, Abraham Ribicoff Research Facilities, New Haven, CT (United States); Matuskey, David [Yale University, Department of Psychiatry, New Haven, CT (United States); Connecticut Mental Health Center, Abraham Ribicoff Research Facilities, New Haven, CT (United States); Yale University, PET Center, Department of Diagnostic Radiology, New Haven, CT (United States); Deserno, Lorenz [Charite - Universitaetsmedizin Berlin, Department of Psychiatry and Psychotherapy, Campus Charite Mitte, Berlin (Germany); Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Berlin (Germany); Neumeister, Alexander [Yale University, Department of Psychiatry, New Haven, CT (United States); Mount Sinai School of Medicine, Department of Psychiatry, New York, NY (United States); VA Connecticut Healthcare System, Clinical Neuroscience Division, VA National Center for PTSD, West Haven, CT (United States); Krystal, John H. [Yale University, Department of Psychiatry, New Haven, CT (United States); Connecticut Mental Health Center, Abraham Ribicoff Research Facilities, New Haven, CT (United States); VA Connecticut Healthcare System, Clinical Neuroscience Division, VA National Center for PTSD, West Haven, CT (United States); Carson, Richard E. [Connecticut Mental Health Center, Abraham Ribicoff Research Facilities, New Haven, CT (United States); Bhagwagar, Zubin [Yale University, Department of Psychiatry, New Haven, CT (United States); Connecticut Mental Health Center, Abraham Ribicoff Research Facilities, New Haven, CT (United States); Bristol-Myers Squibb, Wallingford, CT (United States)

2014-11-27

[{sup 11}C]P943 is a novel, highly selective 5-HT{sub 1B} PET radioligand. The aim of this study was to determine the test-retest reliability of [{sup 11}C]P943 using two different modeling methods and to perform a power analysis with each quantification technique. Seven healthy volunteers underwent two PET scans on the same day. Regions of interest (ROIs) were the amygdala, hippocampus, pallidum, putamen, insula, frontal, anterior cingulate, parietal, temporal and occipital cortices, and cerebellum. Two multilinear radioligand quantification techniques were used to estimate binding potential: MA1, using arterial input function data, and the second version of the multilinear reference tissue model analysis (MRTM2), using the cerebellum as the reference region. Between-scan percent variability and intraclass correlation coefficients (ICC) were used to assess test-retest reliability. We also performed power analyses to determine the method that would allow the least number of subjects using within-subject or between-subject study designs. A voxel-wise ICC analysis for MRTM2 BP{sub ND} was performed for the whole brain and all the ROIs studied. Mean percent variability between two scans across regions ranged between 0.4 % and 12.4 % for MA1 BP{sub ND}, 0.5 % and 11.5 % for MA1 BP{sub P}, 16.7 % and 28.3 % for MA1 BP{sub F}, and between 0.2 % and 5.4 % for MRTM2 BP{sub ND}. The power analyses showed a greater number of subjects were required using MA1 BP{sub F} compared with other outcome measures for both within-subject and between-subject study designs. ICC values were the highest using MRTM2 BP{sub ND} and the lowest with MA1 BP{sub F} in ten ROIs. Small regions and regions with low binding had lower ICC values than large regions and regions with high binding. Reliable measures of 5-HT{sub 1B} receptor binding can be obtained using the novel PET radioligand [{sup 11}C]P943. Quantification of 5-HT{sub 1B} receptor binding with MRTM2 BP{sub ND} and with MA1 BP{sub P

Test-retest reproducibility of the metabotropic glutamate receptor 5 ligand [{sup 18}F]FPEB with bolus plus constant infusion in humans

Energy Technology Data Exchange (ETDEWEB)

Park, Eunkyung; Sullivan, Jenna M.; Planeta, Beata; Gallezot, Jean-Dominique; Lim, Keunpoong; Lin, Shu-Fei; Ropchan, Jim; Huang, Yiyun; Carson, Richard E. [Yale School of Medicine, PET Center, Department of Diagnostic Radiology, 801 Howard Avenue, PO Box 208048, New Haven, CT (United States); McCarthy, Timothy J. [Pfizer Worldwide Research and Development, Cambridge, MA (United States); Ding, Yu-Shin [New York University School of Medicine, Department of Radiology, New York, NY (United States); Morris, Evan D.; Williams, Wendol A. [Yale School of Medicine, PET Center, Department of Diagnostic Radiology, 801 Howard Avenue, PO Box 208048, New Haven, CT (United States); Yale School of Medicine, Department of Psychiatry, New Haven, CT (United States)

2015-09-15

[{sup 18}F]FPEB is a promising PET radioligand for the metabotropic glutamate receptor 5 (mGluR5), a potential target for the treatment of neuropsychiatric diseases. The purpose of this study was to evaluate the test-retest reproducibility of [{sup 18}F]FPEB in the human brain. Seven healthy male subjects were scanned twice, 3 - 11 weeks apart. Dynamic data were acquired using bolus plus infusion of 162 ± 32 MBq [{sup 18}F]FPEB. Four methods were used to estimate volume of distribution (V{sub T}): equilibrium analysis (EQ) using arterial (EQ{sub A}) or venous input data (EQ{sub V}), MA1, and a two-tissue compartment model (2 T). Binding potential (BP{sub ND}) was also estimated using cerebellar white matter (CWM) or gray matter (CGM) as the reference region using EQ, 2 T and MA1. Absolute test-retest variability (aTRV) of V{sub T} and BP{sub ND} were calculated for each method. Venous blood measurements (C{sub V}) were compared with arterial input (C{sub A}) to examine their usability in EQ analysis. Regional V{sub T} estimated by the four methods displayed a high degree of agreement (r{sup 2} ranging from 0.83 to 0.99 among the methods), although EQ{sub A} and EQ{sub V} overestimated V{sub T} by a mean of 9 % and 7 %, respectively, compared to 2 T. Mean values of aTRV of V{sub T} were 11 % by EQ{sub A}, 12 % by EQ{sub V}, 14 % by MA1 and 14 % by 2 T. Regional BP{sub ND} also agreed well among the methods and mean aTRV of BP{sub ND} was 8 - 12 % (CWM) and 7 - 9 % (CGM). Venous and arterial blood concentrations of [{sup 18}F]FPEB were well matched during equilibrium (C{sub V} = 1.01 . C{sub A}, r{sup 2} = 0.95). [{sup 18}F]FPEB binding shows good TRV with minor differences among analysis methods. Venous blood can be used as an alternative for input function measurement instead of arterial blood in EQ analysis. Thus, [{sup 18}F]FPEB is an excellent PET imaging tracer for mGluR5 in humans. (orig.)

Retest effects in working memory capacity tests: A meta-analysis.

Science.gov (United States)

Scharfen, Jana; Jansen, Katrin; Holling, Heinz

2018-06-15

The repeated administration of working memory capacity tests is common in clinical and research settings. For cognitive ability tests and different neuropsychological tests, meta-analyses have shown that they are prone to retest effects, which have to be accounted for when interpreting retest scores. Using a multilevel approach, this meta-analysis aims at showing the reproducibility of retest effects in working memory capacity tests for up to seven test administrations, and examines the impact of the length of the test-retest interval, test modality, equivalence of test forms and participant age on the size of retest effects. Furthermore, it is assessed whether the size of retest effects depends on the test paradigm. An extensive literature search revealed 234 effect sizes from 95 samples and 68 studies, in which healthy participants between 12 and 70 years repeatedly performed a working memory capacity test. Results yield a weighted average of g = 0.28 for retest effects from the first to the second test administration, and a significant increase in effect sizes was observed up to the fourth test administration. The length of the test-retest interval and publication year were found to moderate the size of retest effects. Retest effects differed between the paradigms of working memory capacity tests. These findings call for the development and use of appropriate experimental or statistical methods to address retest effects in working memory capacity tests.

The QUASAR reproducibility study, Part II: Results from a multi-center Arterial Spin Labeling test-retest study

DEFF Research Database (Denmark)

Petersen, Esben Thade; Mouridsen, Kim; Golay, Xavier

2010-01-01

Quantitative STAR labeling of Arterial Regions or QUASAR), a method providing user independent quantification of CBF in a large test-retest study across sites from around the world, dubbed "The QUASAR reproducibility study". Altogether, 28 sites located in Asia, Europe and North America participated...... and a total of 284 healthy volunteers were scanned. Minimal operator dependence was assured by using an automatic planning tool and its accuracy and potential usefulness in multi-center trials was evaluated as well. Accurate repositioning between sessions was achieved with the automatic planning tool showing...

The QUASAR reproducibility study, Part II: Results from a multi-center Arterial Spin Labeling test-retest study

DEFF Research Database (Denmark)

Petersen, Esben; Mouridsen, Kim; Golay, Xavier

2009-01-01

Quantitative STAR labeling of Arterial Regions or QUASAR), a method providing user independent quantification of CBF in a large test-retest study across sites from around the world, dubbed "The QUASAR reproducibility study". Altogether, 28 sites located in Asia, Europe and North America participated...... and a total of 284 healthy volunteers were scanned. Minimal operator dependence was assured by using an automatic planning tool and its accuracy and potential usefulness in multi-center trials was evaluated as well. Accurate repositioning between sessions was achieved with the automatic planning tool showing...

Static and Dynamic Handgrip Strength Endurance: Test-Retest Reproducibility.

Science.gov (United States)

Gerodimos, Vassilis; Karatrantou, Konstantina; Psychou, Dimitra; Vasilopoulou, Theodora; Zafeiridis, Andreas

2017-03-01

This study investigated the reliability of static and dynamic handgrip strength endurance using different protocols and indicators for the assessment of strength endurance. Forty young, healthy men and women (age, 18-22 years) performed 2 handgrip strength endurance protocols: a static protocol (sustained submaximal contraction at 50% of maximal voluntary contraction) and a dynamic one (8, 10, and 12 maximal repetitions). The participants executed each protocol twice to assess the test-retest reproducibility. Total work and total time were used as indicators of strength endurance in the static protocol; the strength recorded at each maximal repetition, the percentage change, and fatigue index were used as indicators of strength endurance in the dynamic protocol. The static protocol showed high reliability irrespective of sex and hand for total time and work. The 12-repetition dynamic protocol exhibited moderate-high reliability for repeated maximal repetitions and percentage change; the 8- and 10-repetition protocols demonstrated lower reliability irrespective of sex and hand. The fatigue index was not a reliable indicator for the assessment of dynamic handgrip endurance. Static handgrip endurance can be measured reliably using the total time and total work as indicators of strength endurance. For the evaluation of dynamic handgrip endurance, the 12-repetition protocol is recommended, using the repeated maximal repetitions and percentage change as indicators of strength endurance. Practitioners should consider the static (50% maximal voluntary contraction) and dynamic (12 repeated maximal repetitions) protocols as reliable for the assessment of handgrip strength endurance. The evaluation of static endurance in conjunction with dynamic endurance would provide more complete information about hand function. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Serotonin transporter binding in the hypothalamus correlates negatively with tonic heat pain ratings in healthy subjects: A [11C]DASB PET study

DEFF Research Database (Denmark)

Kupers, Ron; Frokjaer, Vibe G.; Erritzoe, David

2010-01-01

There is a large body of evidence that the serotonergic system plays an important role in the transmission and regulation of pain. Here we used positron emission tomography (PET) with the serotonin transporter (SERT) tracer [11C]DASB to study the relationship between SERT binding in the brain and....... The negative correlation between SERT binding in the hypothalamus and insula with tonic pain ratings suggests a possible serotonergic control of the role of these areas in the modulation or in the affective appreciation of pain.......) tonic noxious heat stimulus. PET data were analyzed using both volume-of-interest (VOI) and voxel-based approaches. VOI analysis revealed a significant negative correlation between tonic pain ratings and SERT binding in the hypothalamus (r = −0.59; p = 0.008), a finding confirmed by the parametric...... analysis. The parametric analysis also revealed a negative correlation between tonic pain ratings and SERT binding in the right anterior insula. Measures of regional SERT binding did not correlate with pain threshold or with responses to short phasic suprathreshold phasic heat stimuli. Finally, the VOI...

Test-retest reliability and predictive validity of the Implicit Association Test in children.

Science.gov (United States)

Rae, James R; Olson, Kristina R

2018-02-01

The Implicit Association Test (IAT) is increasingly used in developmental research despite minimal evidence of whether children's IAT scores are reliable across time or predictive of behavior. When test-retest reliability and predictive validity have been assessed, the results have been mixed, and because these studies have differed on many factors simultaneously (lag-time between testing administrations, domain, etc.), it is difficult to discern what factors may explain variability in existing test-retest reliability and predictive validity estimates. Across five studies (total N = 519; ages 6- to 11-years-old), we manipulated two factors that have varied in previous developmental research-lag-time and domain. An internal meta-analysis of these studies revealed that, across three different methods of analyzing the data, mean test-retest (rs of .48, .38, and .34) and predictive validity (rs of .46, .20, and .10) effect sizes were significantly greater than zero. While lag-time did not moderate the magnitude of test-retest coefficients, whether we observed domain differences in test-retest reliability and predictive validity estimates was contingent on other factors, such as how we scored the IAT or whether we included estimates from a unique sample (i.e., a sample containing gender typical and gender diverse children). Recommendations are made for developmental researchers that utilize the IAT in their research. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Measurement of central μ-opioid receptor binding in vivo with PET and [11C]carfentanil: a test-retest study in healthy subjects

International Nuclear Information System (INIS)

Hirvonen, Jussi; Aalto, Sargo; Maksimow, Anu; Oikonen, Vesa; Naagren, Kjell; Hagelberg, Nora; Scheinin, Harry; Ingman, Kimmo; Virkkala, Jussi

2009-01-01

[ 11 C]Carfentanil has been widely used in positron emission tomography (PET) studies for measuring μ-opioid receptor binding in humans, but the reproducibility of the binding parameter estimates is unknown. Eight healthy volunteers were scanned twice during the same day with [ 11 C]carfentanil PET, and binding to receptors was assessed with both reference tissue and arterial plasma input-based models using region of interest (ROI) and voxel-based quantification. The two-tissue compartmental model distribution volume (V T ) was highly reproducible as indicated by low variability (VAR 0.93). BP ND (BP relative to the nondisplaceable tissue compartment) was also highly reproducible (VAR 0.90) both at ROI- and voxel-level, and reference tissue-based models provided stable estimates after 40 min. The reproducibility of [ 11 C]carfentanil binding parameter estimates is excellent with outcome measures based on both arterial plasma and reference tissue input, and a scanning time of 40 min appears sufficient. (orig.)

Test-retest reproducibility of accommodative facility measures in primary school children.

Science.gov (United States)

Adler, Paul; Scally, Andrew J; Barrett, Brendan T

2018-05-08

To determine the test-retest reproducibility of accommodative facility (AF) measures in an unselected sample of UK primary school children. Using ±2.00 DS flippers and a viewing distance of 40 cm, AF was measured in 136 children (range 4-12 years, average 8.1 ± 2.1) by five testers on three occasions (average interval between successive tests: eight days, range 1-21 days). On each occasion, AF was measured monocularly and binocularly, for two minutes. Full datasets were obtained in 111 children (81.6 per cent). Intra-individual variation in AF was large (standard deviation [SD] = 3.8 cycles per minute [cpm]) and there was variation due to the identity of the tester (SD = 1.6 cpm). On average, AF was greater: (i) in monocular compared to binocular testing (by 1.4 cpm, p cpm, p cpm lower than in children ≥ 10 years old, p = 0.009); and (iv) on subsequent testing occasions (for example, visit-2 AF was 2.0 cpm higher than visit-1 AF, p cpm monocularly and ≥ 8 cpm binocularly), but this rose to 83.8 per cent after the third test. Using less stringent pass criteria (≥ 6 cpm monocularly and ≥ 3 cpm binocularly), the equivalent figures were 82.9 and 96.4 per cent, respectively. Reduced AF did not co-exist with abnormal near point of accommodation or reduced visual acuity. The results reveal considerable intra-individual variability in raw AF measures in children. When the results are considered as pass/fail, children who initially exhibit normal AF continued to do so on repeat testing. Conversely, the vast majority of children with initially reduced AF exhibit normal performance on repeat testing. Using established pass/fail criteria, the prevalence of persistently reduced AF in this sample is 3.6 per cent. © 2018 Optometry Australia.

Test re-test reliability and construct validity of the star-track test of manual dexterity

DEFF Research Database (Denmark)

Kildebro, Niels; Amirian, Ilda; Gögenur, Ismail

2015-01-01

Objectives. We wished to determine test re-test reliability and construct validity of the star-track test of manual dexterity. Design. Test re-test reliability was examined in a controlled study. Construct validity was tested in a blinded randomized crossover study. Setting. The study was performed...... at a university hospital in Denmark. Participants. A total of 11 subjects for test re-test and 20 subjects for the construct validity study were included. All subjects were healthy volunteers. Intervention. The test re-test trial had two measurements with 2 days pause in between. The interventions...... in the construct validity study included baseline measurement, intervention 1: fatigue, intervention 2: stress, and intervention 3: fatigue and stress. There was a 2 day pause between each intervention. Main outcome measure. An integrated measure of completion time and number of errors was used. Results. All...

The effect of sample storage on the performance and reproducibility of the galactomannan EIA test.

Science.gov (United States)

Kimpton, George; White, P Lewis; Barnes, Rosemary A

2014-08-01

Galactomannan enzyme immune assay (GM EIA) is a nonculture test for detecting invasive aspergillosis (IA) forming a key part of diagnosis and management. Recent reports have questioned the reproducibility of indices after sample storage. To investigate this, 198 serum samples (72 from cases and 126 from controls) and 61 plasma samples (24 from cases and 37 from controls), initially tested between 2010 and 2013, were retested to determine any change in index. Data were also collected on circulatory protein levels for false-positive serum samples. Serum indices significantly declined on retesting (median: initial, 0.50, retest, 0.23; P < 0.0001). This was shown to be diagnosis dependent as the decline was apparent on retesting of control samples (median: initial 0.50, retest 0.12; P < 0.0001), but was not evident with case samples (median: initial, 0.80, retest, 0.80; P = 0.724). Plasma samples showed little change on reanalysis after long-term storage at 4°C. Retesting after freezing showed a decrease in index values for controls (median: initial 0.40, retest 0.26; P = 0.0505), but no significant change in cases. Circulatory proteins showed a correlation between serum albumin concentration and difference in index value on retesting. Overall, this study suggests that a lack of reproducibility in GM EIA positivity is only significant when disease is absent. Retesting after freezing helps to differentiate false-positive GM EIA results and, with consecutive positivity, could help to improve accuracy in predicting disease status. The freezing of samples prior to testing could potentially reduce false-positivity rates and the need to retest. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Serotonin 2A receptor agonist binding in the human brain with [¹¹C]Cimbi-36

DEFF Research Database (Denmark)

Ettrup, Anders; Svarer, Claus; McMahon, Brenda

2016-01-01

INTRODUCTION: [(11)C]Cimbi-36 is a recently developed serotonin 2A (5-HT2A) receptor agonist positron emission tomography (PET) radioligand that has been successfully applied for human neuroimaging. Here, we investigate the test-retest variability of cerebral [(11)C]Cimbi-36 PET and compare [(11)C...... test-retest variability in [(11)C]Cimbi-36 binding measures, and another eight were scanned after a bolus plus constant infusion with [(18)F]altanserin. Regional differences in the brain distribution of [(11)C]Cimbi-36 and [(18)F]altanserin were assessed with a correlation of regional binding measures...... and with voxel-based analysis. RESULTS: Test-retest variability of [(11)C]Cimbi-36 non-displaceable binding potential (BPND) was consistently correlation between regional...

Test-retest repeatability of myocardial oxidative metabolism and efficiency using standalone dynamic 11C-acetate PET and multimodality approaches in healthy controls.

Science.gov (United States)

Hansson, Nils Henrik; Harms, Hendrik Johannes; Kim, Won Yong; Nielsen, Roni; Tolbod, Lars P; Frøkiær, Jørgen; Bouchelouche, Kirsten; Poulsen, Steen Hvitfeldt; Wiggers, Henrik; Parner, Erik Thorlund; Sörensen, Jens

2018-05-31

Myocardial efficiency measured by 11 C-acetate positron emission tomography (PET) has successfully been used in clinical research to quantify mechanoenergetic coupling. The objective of this study was to establish the repeatability of myocardial external efficiency (MEE) and work metabolic index (WMI) by non-invasive concepts. Ten healthy volunteers (63 ± 4 years) were examined twice, one week apart, using 11 C-acetate PET, cardiovascular magnetic resonance (CMR), and echocardiography. Myocardial oxygen consumption from PET was combined with stroke work data from CMR, echocardiography, or PET to obtain MEE and WMI for each modality. Repeatability was estimated as the coefficient of variation (CV) between test and retest. MEE CMR , MEE Echo , and MEE PET values were 21.9 ± 2.7%, 16.4 ± 3.7%, and 23.8 ± 4.9%, respectively, P PET values were 4.42 ± 0.90, 4.07 ± 0.63, and 4.58 ± 1.13 mmHg × mL/m 2  × 10 6 , respectively, P = .45. Repeatability for MEE CMR was superior compared with MEE Echo but did not differ significantly compared with MEE PET (6.3% vs 12.9% and 9.4%, P = .04 and .25). CV values for WMI CMR , WMI Echo , and WMI PET were 10.0%, 14.8%, and 12.0%, respectively, (P = .53). Non-invasive measurements of MEE using 11 C-acetate PET are highly repeatable. A PET-only approach did not differ significantly from CMR/PET and might facilitate further clinical research due to lower costs and broader applicability.

Brain Serotonin Transporter Occupancy by Oral Sibutramine Dosed to Steady State: A PET Study Using 11C-DASB in Healthy Humans

Science.gov (United States)

Talbot, Peter S; Bradley, Stefan; Clarke, Cyril P; Babalola, Kola O; Philipp, Andrew W; Brown, Gavin; McMahon, Adam W; Matthews, Julian C

2010-01-01

Sibutramine is a centrally acting monoamine reuptake inhibitor prescribed as an appetite suppressant in the management of obesity. Its effects are mostly attributable to serotonin and norepinephrine transporter (SERT and NET, respectively) inhibition by its potent metabolites mono-desmethylsibutramine (M1) and di-desmethylsibutramine (M2). However, there is a paucity of in vivo data in humans about mechanisms underlying both clinical efficacy and the dose-independent non-response observed in a minority of patients. Twelve healthy male patients (mean age 41 years) completed a double-blind, placebo-controlled, within-subject crossover investigation of brain SERT occupancy by sibutramine 15 mg daily at steady state. Correlations were measured between occupancy and (i) plasma concentrations of sibutramine, M1 and M2; (ii) appetite suppression. 11C-DASB PET scans were performed on the HRRT camera. Binding potentials (BPND) were calculated by the Logan reference tissue (cerebellum) method. SERT occupancy was modest (mean 30±10%), was similar across brain regions, but varied widely across subjects (15–46%). Occupancy was correlated positively (p=0.09) with M2 concentration, but not with sibutramine or M1. No significant appetite suppression was seen at sibutramine is of modest magnitude and may be mediated predominantly by M2 in humans. 5-HT reuptake inhibition may be necessary but is not sufficient for sibutramine's efficacy in humans, supporting preclinical data suggesting that the hypophagic effect requires the co-inhibition of both SERT and NET. PMID:19890256

Test–Retest Reproducibility of the Microperimeter MP3 With Fundus Image Tracking in Healthy Subjects and Patients With Macular Disease

Science.gov (United States)

Palkovits, Stefan; Hirnschall, Nino; Georgiev, Stefan; Leisser, Christoph

2018-01-01

Purpose To evaluate the test–retest reproducibility of a novel microperimeter with fundus image tracking (MP3, Nidek Co, Japan) in healthy subjects and patients with macular disease. Methods Ten healthy subjects and 20 patients suffering from range of macular diseases were included. After training measurements, two additional microperimetry measurements were scheduled. Test–retest reproducibility was assessed for mean retinal sensitivity, pointwise sensitivity, and deep scotoma size using the coefficient of repeatability and Bland-Altman diagrams. In addition, in a subgroup of patients microperimetry was compared with conventional perimetry. Results Average differences in mean retinal sensitivity between the two study measurements were 0.26 ± 1.7 dB (median 0 dB; interquartile range [IQR] −1 to 1) for the healthy and 0.36 ± 2.5 dB (median 0 dB; IQR −1 to 2) for the macular patient group. Coefficients of repeatability for mean retinal sensitivity and pointwise retinal sensitivity were 1.2 and 3.3 dB for the healthy subjects and 1.6 and 5.0 dB for the macular disease patients, respectively. Absolute agreement in deep scotoma size between both study days was found in 79.9% of the test loci. Conclusion The microperimeter MP3 shows an adequate test–retest reproducibility for mean retinal sensitivity, pointwise retinal sensitivity, and deep scotoma size in healthy subjects and patients suffering from macular disease. Furthermore, reproducibility of microperimetry is higher than conventional perimetry. Translational Relevance Reproducibility is an important measure for each diagnostic device. Especially in a clinical setting high reproducibility set the basis to achieve reliable results using the specific device. Therefore, assessment of the reproducibility is of eminent importance to interpret the findings of future studies. PMID:29430338

Test–retest repeatability of quantitative cardiac 11C-meta-hydroxyephedrine measurements in rats by small animal positron emission tomography

International Nuclear Information System (INIS)

Thackeray, James T.; Renaud, Jennifer M.; Kordos, Myra; Klein, Ran; Kemp, Robert A. de; Beanlands, Rob S.B.; DaSilva, Jean N.

2013-01-01

Introduction: The norepinephrine analogue 11 C-meta-hydroxyephedrine (HED) has been used to interrogate sympathetic neuronal reuptake in cardiovascular disease. Application for longitudinal studies in small animal models of disease necessitates an understanding of test–retest variability. This study evaluated the repeatability of multiple quantitative cardiac measurements of HED retention and washout and the pharmacological response to reuptake blockade and enhanced norepinephrine levels. Methods: Small animal PET images were acquired over 60 min following HED administration to healthy male Sprague Dawley rats. Paired test and retest scans were undertaken in individual animals over 7 days. Additional HED scans were conducted following administration of norepinephrine reuptake inhibitor desipramine or continuous infusion of exogenous norepinephrine. HED retention was quantified by retention index, standardized uptake value (SUV), monoexponential and one-compartment washout. Plasma and cardiac norepinephrine were measured by high performance liquid chromatography. Results: Test retest variability was lower for retention index (15% ± 12%) and SUV (19% ± 15%) as compared to monoexponential washout rates (21% ± 13%). Desipramine pretreatment reduced myocardial HED retention index by 69% and SUV by 85%. Chase treatment with desipramine increased monoexponential HED washout by 197% compared to untreated controls. Norepinephrine infusion dose-dependently reduced HED accumulation, reflected by both retention index and SUV, with a corresponding increase in monoexponential washout. Plasma and cardiac norepinephrine levels correlated with HED quantitative measurements. Conclusion: The repeatability of HED retention index, SUV, and monoexponential washout supports its suitability for longitudinal PET studies in rats. Uptake and washout of HED are sensitive to acute increases in norepinephrine concentration

Test-retest reliability of the Progressive Isoinertial Lifting Evaluation (PILE).

Science.gov (United States)

Lygren, Hildegunn; Dragesund, Tove; Joensen, Jón; Ask, Tove; Moe-Nilssen, Rolf

2005-05-01

A repeated measures single group design. To investigate test-retest reliability of Progressive Isoinertial Lifting Evaluation on patients with long lasting musculoskeletal problems related to the lumbar spine. Test-retest reliability has been satisfactory in healthy men. Test-retest reliability for clinical populations has not been reported. A total of 31 patients (17 women and 14 men) with long lasting low back pain participated in the study. The patients were tested twice at an interval of 2 days and at the same time of the day. The heaviest load that the patient could lift 4 times was used as outcome measure. The error of measurement indicates that the true result in 95% of cases will be within +/-4.5 kg from the measured value, while the difference between 2 measurements in 95% of cases will be less than 6.4 kg. Intra-class correlation (1,1) was 0.91. Relative test-retest reliability was high assessed by intra-class correlation, but absolute measurement variability reported as the smallest detectable difference has relevance for the interpretation of clinical test results and should also be considered.

Rorschach e pedofilia: a fidedignidade no teste-reteste = Rorschach and pedophilia: a reliability at test-retest

Directory of Open Access Journals (Sweden)

Scortegagna, Silvana Alba

2013-01-01

Full Text Available Esse estudo buscou investigar as características de personalidade de um indivíduo pedófilo, e evidenciar a fidedignidade do Rorschach no teste-reteste. O participante, com 38 anos de idade, masculino, respondeu a entrevista e ao método de Rorschach, em duas etapas. Os principais achados revelam: a uma tendência à fragmentação na percepção de si e dos outros; b autoimagem negativa e desfavorável em relação ao corpo e suas funções; c problemas nas relações interpessoais, falhas na capacidade de empatia; d déficit no ajustamento perceptivo da realidade; e vulnerabilidade a pressões subjetivas e impulsividade. Esses resultados mantiveram-se estáveis comparando-se as duas aplicações, permitindo ampliar a compreensão dos elementos psicológicos envolvidos na pedofilia, que se mantem, e apoiam a fidedignidade do Rorschach no teste-reteste

Test-retest reliability of an interactive voice response (IVR) version of the EORTC QLQ-C30

NARCIS (Netherlands)

Lundy, J.J.; Coons, S.J.; Aaronson, N.K.

2015-01-01

Objective: The objective of this study was to assess the test-retest reliability of an interactive voice response (IVR) version of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30. Methods: A convenience sample of outpatient cancer clinic patients (n = 127) was asked to

Central serotonin transporter availability in highly obese individuals compared with non-obese controls: A [11C] DASB positron emission tomography study

International Nuclear Information System (INIS)

Hesse, Swen; Sabri, Osama; Rullmann, Michael; Luthardt, Julia; Becker, Georg-Alexander; Bresch, Anke; Patt, Marianne; Meyer, Philipp M.; Winter, Karsten; Hankir, Mohammed K.; Zientek, Franziska; Reissig, Georg; Drabe, Mandy; Regenthal, Ralf; Schinke, Christian; Arelin, Katrin; Lobsien, Donald; Fasshauer, Mathias; Fenske, Wiebke K.; Stumvoll, Michael; Blueher, Matthias

2016-01-01

The role of the central serotonin (5-hydroxytryptamine, 5-HT) system in feeding has been extensively studied in animals with the 5-HT family of transporters (5-HTT) being identified as key molecules in the regulation of satiety and body weight. Aberrant 5-HT transmission has been implicated in the pathogenesis of human obesity by in vivo positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging techniques. However, results obtained thus far from studies of central 5-HTT availability have been inconsistent, which is thought to be brought about mainly by the low number of individuals with a high body mass index (BMI) previously used. The aim of this study was therefore to assess 5-HTT availability in the brains of highly obese otherwise healthy individuals compared with non-obese healthy controls. We performed PET using the 5-HTT selective radiotracer [ 11 C] DASB on 30 highly obese (BMI range between 35 and 55 kg/m 2 ) and 15 age- and sex-matched non-obese volunteers (BMI range between 19 and 27 kg/m 2 ) in a cross-sectional study design. The 5-HTT binding potential (BP ND ) was used as the outcome parameter. On a group level, there was no significant difference in 5-HTT BP ND in various cortical and subcortical regions in individuals with the highest BMI compared with non-obese controls, while statistical models showed minor effects of age, sex, and the degree of depression on 5-HTT BP ND . The overall finding of a lack of significantly altered 5-HTT availability together with its high variance in obese individuals justifies the investigation of individual behavioral responses to external and internal cues which may further define distinct phenotypes and subgroups in human obesity. (orig.)

A PHYSICAL ACTIVITY QUESTIONNAIRE: REPRODUCIBILITY AND VALIDITY

Directory of Open Access Journals (Sweden)

Nicolas Barbosa

2007-12-01

Full Text Available This study evaluates the Quantification de L'Activite Physique en Altitude chez les Enfants (QAPACE supervised self-administered questionnaire reproducibility and validity on the estimation of the mean daily energy expenditure (DEE on Bogotá's schoolchildren. The comprehension was assessed on 324 students, whereas the reproducibility was studied on a different random sample of 162 who were exposed twice to it. Reproducibility was assessed using both the Bland-Altman plot and the intra-class correlation coefficient (ICC. The validity was studied in a sample of 18 girls and 18 boys randomly selected, which completed the test - re-test study. The DEE derived from the questionnaire was compared with the laboratory measurement results of the peak oxygen uptake (Peak VO2 from ergo-spirometry and Leger Test. The reproducibility ICC was 0.96 (95% C.I. 0.95-0.97; by age categories 8-10, 0.94 (0.89-0. 97; 11-13, 0.98 (0.96- 0.99; 14-16, 0.95 (0.91-0.98. The ICC between mean TEE as estimated by the questionnaire and the direct and indirect Peak VO2 was 0.76 (0.66 (p<0.01; by age categories, 8-10, 11-13, and 14-16 were 0.89 (0.87, 0.76 (0.78 and 0.88 (0.80 respectively. The QAPACE questionnaire is reproducible and valid for estimating PA and showed a high correlation with the Peak VO2 uptake

Test-retest reliability of tibiofemoral joint space width measurements made using a low-dose standing CT scanner

Energy Technology Data Exchange (ETDEWEB)

Segal, Neil A. [University of Kansas Medical Center, Department of Rehabilitation Medicine, 3901 Rainbow Boulevard, Mailstop 1046, Kansas City, KS (United States); The University of Iowa, Iowa City, IA (United States); Bergin, John; Kern, Andrew; Findlay, Christian [The University of Iowa, Iowa City, IA (United States); Anderson, Donald D. [The University of Iowa, Department of Orthopaedics and Rehabilitation, Iowa City, IA (United States)

2017-02-15

To determine the test-retest reliability of knee joint space width (JSW) measurements made using standing CT (SCT) imaging. This prospective two-visit study included 50 knees from 30 subjects (66% female; mean ± SD age 58.2 ± 11.3 years; BMI 29.1 ± 5.6 kg/m{sup 2}; 38% KL grade 0-1). Tibiofemoral geometry was obtained from bilateral, approximately 20 fixed-flexed SCT images acquired at visits 2 weeks apart. For each compartment, the total joint area was defined as the area with a JSW <10 mm. The summary measurements of interest were the percentage of the total joint area with a JSW less than 0.5-mm thresholds between 2.0 and 5.0 mm in each tibiofemoral compartment. Test-retest reliability of the summary JSW measurements was assessed by intraclass correlation coefficients (ICC 2,1) for the percentage area engaged at each threshold of JSW and root-mean-square errors (RMSE) were calculated to assess reproducibility. The ICCs were excellent for each threshold assessed, ranging from 0.95 to 0.97 for the lateral and 0.90 to 0.97 for the medial compartment. RMSE ranged from 1.1 to 7.2% for the lateral and from 3.1 to 9.1% for the medial compartment, with better reproducibility at smaller JSW thresholds. The knee joint positioning protocol used demonstrated high day-to-day reliability for SCT 3D tibiofemoral JSW summary measurements repeated 2 weeks apart. Low-dose SCT provides a great deal of information about the joint while maintaining high reliability, making it a suitable alternative to plain radiographs for evaluating JSW in people with knee OA. (orig.)

Test-retest reliability of tibiofemoral joint space width measurements made using a low-dose standing CT scanner

International Nuclear Information System (INIS)

Segal, Neil A.; Bergin, John; Kern, Andrew; Findlay, Christian; Anderson, Donald D.

2017-01-01

To determine the test-retest reliability of knee joint space width (JSW) measurements made using standing CT (SCT) imaging. This prospective two-visit study included 50 knees from 30 subjects (66% female; mean ± SD age 58.2 ± 11.3 years; BMI 29.1 ± 5.6 kg/m 2 ; 38% KL grade 0-1). Tibiofemoral geometry was obtained from bilateral, approximately 20 fixed-flexed SCT images acquired at visits 2 weeks apart. For each compartment, the total joint area was defined as the area with a JSW <10 mm. The summary measurements of interest were the percentage of the total joint area with a JSW less than 0.5-mm thresholds between 2.0 and 5.0 mm in each tibiofemoral compartment. Test-retest reliability of the summary JSW measurements was assessed by intraclass correlation coefficients (ICC 2,1) for the percentage area engaged at each threshold of JSW and root-mean-square errors (RMSE) were calculated to assess reproducibility. The ICCs were excellent for each threshold assessed, ranging from 0.95 to 0.97 for the lateral and 0.90 to 0.97 for the medial compartment. RMSE ranged from 1.1 to 7.2% for the lateral and from 3.1 to 9.1% for the medial compartment, with better reproducibility at smaller JSW thresholds. The knee joint positioning protocol used demonstrated high day-to-day reliability for SCT 3D tibiofemoral JSW summary measurements repeated 2 weeks apart. Low-dose SCT provides a great deal of information about the joint while maintaining high reliability, making it a suitable alternative to plain radiographs for evaluating JSW in people with knee OA. (orig.)

Central serotonin transporter availability in highly obese individuals compared with non-obese controls: A [{sup 11}C] DASB positron emission tomography study

Energy Technology Data Exchange (ETDEWEB)

Hesse, Swen; Sabri, Osama [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Integrated Research and Treatment Centre Adiposity Diseases Leipzig, Leipzig (Germany); Rullmann, Michael [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Integrated Research and Treatment Centre Adiposity Diseases Leipzig, Leipzig (Germany); Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Leipzig (Germany); Luthardt, Julia; Becker, Georg-Alexander; Bresch, Anke; Patt, Marianne; Meyer, Philipp M. [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Winter, Karsten [University of Leipzig, Centre for Translational Regenerative Medicine, Leipzig (Germany); University of Leipzig, Institute for Medical Informatics, Statistics, and Epidemiology, Leipzig (Germany); Hankir, Mohammed K.; Zientek, Franziska; Reissig, Georg; Drabe, Mandy [Integrated Research and Treatment Centre Adiposity Diseases Leipzig, Leipzig (Germany); Regenthal, Ralf [University of Leipzig, Division of Clinical Pharmacology, Rudolf Boehm Institute of Pharmacology and Toxicology, Leipzig (Germany); Schinke, Christian [University of Leipzig, Department of Neurology, Leipzig (Germany); Arelin, Katrin [Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Leipzig (Germany); University of Leipzig, Day Clinic for Cognitive Neurology, Leipzig (Germany); Lobsien, Donald [University of Leipzig, Department of Neuroradiology, Leipzig (Germany); Fasshauer, Mathias; Fenske, Wiebke K.; Stumvoll, Michael [Integrated Research and Treatment Centre Adiposity Diseases Leipzig, Leipzig (Germany); University of Leipzig, Medical Department III, Leipzig (Germany); Blueher, Matthias [University of Leipzig, Medical Department III, Leipzig (Germany); University of Leipzig, Collaborative Research Centre 1052 Obesity Mechanisms, Leipzig (Germany)

2016-06-15

The role of the central serotonin (5-hydroxytryptamine, 5-HT) system in feeding has been extensively studied in animals with the 5-HT family of transporters (5-HTT) being identified as key molecules in the regulation of satiety and body weight. Aberrant 5-HT transmission has been implicated in the pathogenesis of human obesity by in vivo positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging techniques. However, results obtained thus far from studies of central 5-HTT availability have been inconsistent, which is thought to be brought about mainly by the low number of individuals with a high body mass index (BMI) previously used. The aim of this study was therefore to assess 5-HTT availability in the brains of highly obese otherwise healthy individuals compared with non-obese healthy controls. We performed PET using the 5-HTT selective radiotracer [{sup 11}C] DASB on 30 highly obese (BMI range between 35 and 55 kg/m{sup 2}) and 15 age- and sex-matched non-obese volunteers (BMI range between 19 and 27 kg/m{sup 2}) in a cross-sectional study design. The 5-HTT binding potential (BP{sub ND}) was used as the outcome parameter. On a group level, there was no significant difference in 5-HTT BP{sub ND} in various cortical and subcortical regions in individuals with the highest BMI compared with non-obese controls, while statistical models showed minor effects of age, sex, and the degree of depression on 5-HTT BP{sub ND}. The overall finding of a lack of significantly altered 5-HTT availability together with its high variance in obese individuals justifies the investigation of individual behavioral responses to external and internal cues which may further define distinct phenotypes and subgroups in human obesity. (orig.)

Test-retest reliability of cognitive EEG

Science.gov (United States)

McEvoy, L. K.; Smith, M. E.; Gevins, A.

2000-01-01

OBJECTIVE: Task-related EEG is sensitive to changes in cognitive state produced by increased task difficulty and by transient impairment. If task-related EEG has high test-retest reliability, it could be used as part of a clinical test to assess changes in cognitive function. The aim of this study was to determine the reliability of the EEG recorded during the performance of a working memory (WM) task and a psychomotor vigilance task (PVT). METHODS: EEG was recorded while subjects rested quietly and while they performed the tasks. Within session (test-retest interval of approximately 1 h) and between session (test-retest interval of approximately 7 days) reliability was calculated for four EEG components: frontal midline theta at Fz, posterior theta at Pz, and slow and fast alpha at Pz. RESULTS: Task-related EEG was highly reliable within and between sessions (r0.9 for all components in WM task, and r0.8 for all components in the PVT). Resting EEG also showed high reliability, although the magnitude of the correlation was somewhat smaller than that of the task-related EEG (r0.7 for all 4 components). CONCLUSIONS: These results suggest that under appropriate conditions, task-related EEG has sufficient retest reliability for use in assessing clinical changes in cognitive status.

Minimum joint space width (mJSW) of patellofemoral joint on standing ''skyline'' radiographs: test-retest reproducibility and comparison with quantitative magnetic resonance imaging (qMRI)

International Nuclear Information System (INIS)

Simoni, Paolo; Jamali, Sanaa; Alvarez Miezentseva, Victoria; Albert, Adelin; Totterman, Saara; Schreyer, Edward; Tamez-Pena, Jose G.; Zobel, Bruno Beomonte; Gillet, Philippe

2013-01-01

To assess the intraobserver, interobserver, and test-retest reproducibility of minimum joint space width (mJSW) measurement of medial and lateral patellofemoral joints on standing ''skyline'' radiographs and to compare the mJSW of the patellofemoral joint to the mean cartilage thickness calculated by quantitative magnetic resonance imaging (qMRI). A couple of standing ''skyline'' radiographs of the patellofemoral joints and MRI of 55 knees of 28 volunteers (18 females, ten males, mean age, 48.5 ± 16.2 years) were obtained on the same day. The mJSW of the patellofemoral joint was manually measured and Kellgren and Lawrence grade (KLG) was independently assessed by two observers. The mJSW was compared to the mean cartilage thickness of patellofemoral joint calculated by qMRI. mJSW of the medial and lateral patellofemoral joint showed an excellent intraobserver agreement (interclass correlation (ICC) = 0.94 and 0.96), interobserver agreement (ICC = 0.90 and 0.95) and test-retest agreement (ICC = 0.92 and 0.96). The mJSW measured on radiographs was correlated to mean cartilage thickness calculated by qMRI (r = 0.71, p < 0.0001 for the medial PFJ and r = 0.81, p < 0.0001 for the lateral PFJ). However, there was a lack of concordance between radiographs and qMRI for extreme values of joint width and KLG. Radiographs yielded higher joint space measures than qMRI in knees with a normal joint space, while qMRI yielded higher joint space measures than radiographs in knees with joint space narrowing and higher KLG. Standing ''skyline'' radiographs are a reproducible tool for measuring the mJSW of the patellofemoral joint. The mJSW of the patellofemoral joint on radiographs are correlated with, but not concordant with, qMRI measurements. (orig.)

Intra-Rater Reproducibility and Validity of Nintendo Wii Balance Testing in Community-Dwelling Older Adults

DEFF Research Database (Denmark)

Jørgensen, Martin Grønbech; Laessoe, Uffe; Hendriksen, Carsten

2014-01-01

The aims of the current study were to (1) examine the intra-rater inter-session reproducibility of the Nintendo Wii Agility and Stillness tests and (2) explore the concurrent validity in relation to 'gold-standard' force plate analysis. Within-day inter-session reproducibility was examined in 30 ...... older adults (age 71.8±5.1 yrs.). No systematic test-retest differences were found for the Wii Stillness test, however, the Wii Agility test scores differed systematically between test sessions (p...

Evaluation of 11C-BU99008, a positron emission tomography ligand for the Imidazoline2 binding site in human brain.

Science.gov (United States)

Tyacke, Robin J; Myers, Jim F M; Venkataraman, Ashwin; Mick, Inge; Turton, Samuel; Passchier, Jan; Husbands, Stephen M; Rabiner, Eugenii Ilan A; Gunn, Roger N; Murphy, Philip S; Parker, Christine A; Nutt, David J

2018-03-09

The imidazoline 2 binding site (I 2 BS), are thought to be expressed in glia, and implicated in the regulation of glial fibrillary acidic protein. A PET ligand for this target would be important for the investigation of neurodegenerative and neuroinflammatory diseases. 11 C-BU99008 has previously been identified as a putative PET radioligand. Here we present the first in vivo characterisation of this PET radioligand in humans and assess its test-retest reproducibility. Methods 14 healthy male volunteers underwent dynamic PET imaging with 11 C-BU99008 and arterial sampling. Six subjects were used to assess test-retest and eight were used in the pharmacological evaluation, undergoing a second, or third heterologous competition scan with the mixed I 2 BS/α 2 -adrenoceptor drug, idazoxan (n=8; 20, 40, 60 and 80mg) and the mixed irreversible MAO A/B inhibitor, isocarboxazid (n=4; 50mg), respectively. Regional time-activity data were generated from arterial plasma input functions corrected for metabolites using the most appropriate model to derive the outcome measure V T (regional total distribution volume). All image processing and kinetic analysis was performed in MIAKAT™ (www.miakat.org). Results Brain uptake of 11 C-BU99008 was good with reversible kinetics and a heterogeneous distribution consistent with known I 2 BS expression. Model selection criteria indicated that the 2-tissue-compartment was preferred. V T estimates were high in the striatum (113±20 mL·cm -3 ), medium in cortex frontal lobe (55±9 mL·cm -3 ) and low in the cerebellum (47±7 mL·cm -3 ). Test-retest reliability was found to be reasonable. The uptake was dose-dependently reduced by pre-treatment with idazoxan throughout the brain, with an average block across all regions of ~60% ( V T = ~30 mL·cm -3 ) at the highest dose (80 mg). The ED 50 for idazoxan was calculated as 33.1 mg. Uptake was not blocked by pre-treatment with the MAO inhibitor, isocarboxazid. Conclusions In summary, 11 C

Evaluating the reliability of an injury prevention screening tool: Test-retest study.

Science.gov (United States)

Gittelman, Michael A; Kincaid, Madeline; Denny, Sarah; Wervey Arnold, Melissa; FitzGerald, Michael; Carle, Adam C; Mara, Constance A

2016-10-01

A standardized injury prevention (IP) screening tool can identify family risks and allow pediatricians to address behaviors. To assess behavior changes on later screens, the tool must be reliable for an individual and ideally between household members. Little research has examined the reliability of safety screening tool questions. This study utilized test-retest reliability of parent responses on an existing IP questionnaire and also compared responses between household parents. Investigators recruited parents of children 0 to 1 year of age during admission to a tertiary care children's hospital. When both parents were present, one was chosen as the "primary" respondent. Primary respondents completed the 30-question IP screening tool after consent, and they were re-screened approximately 4 hours later to test individual reliability. The "second" parent, when present, only completed the tool once. All participants received a 10-dollar gift card. Cohen's Kappa was used to estimate test-retest reliability and inter-rater agreement. Standard test-retest criteria consider Kappa values: 0.0 to 0.40 poor to fair, 0.41 to 0.60 moderate, 0.61 to 0.80 substantial, and 0.81 to 1.00 as almost perfect reliability. One hundred five families participated, with five lost to follow-up. Thirty-two (30.5%) parent dyads completed the tool. Primary respondents were generally mothers (88%) and Caucasian (72%). Test-retest of the primary respondents showed their responses to be almost perfect; average 0.82 (SD = 0.13, range 0.49-1.00). Seventeen questions had almost perfect test-retest reliability and 11 had substantial reliability. However, inter-rater agreement between household members for 12 objective questions showed little agreement between responses; inter-rater agreement averaged 0.35 (SD = 0.34, range -0.19-1.00). One question had almost perfect inter-rater agreement and two had substantial inter-rater agreement. The IP screening tool used by a single individual had excellent

Test-retest reliability of the multifocal photopic negative response.

Science.gov (United States)

Van Alstine, Anthony W; Viswanathan, Suresh

2017-02-01

To assess the test-retest reliability of the multifocal photopic negative response (mfPhNR) of normal human subjects. Multifocal electroretinograms were recorded from one eye of 61 healthy adult subjects on two separate days using a Visual Evoked Response Imaging System software version 4.3 (EDI, San Mateo, California). The visual stimulus delivered on a 75-Hz monitor consisted of seven equal-sized hexagons each subtending 12° of visual angle. The m-step exponent was 9, and the m-sequence was slowed to include at least 30 blank frames after each flash. Only the first slice of the first-order kernel was analyzed. The mfPhNR amplitude was measured at a fixed time in the trough from baseline (BT) as well as at the same fixed time in the trough from the preceding b-wave peak (PT). Additionally, we also analyzed BT normalized either to PT (BT/PT) or to the b-wave amplitude (BT/b-wave). The relative reliability of test-retest differences for each test location was estimated by the Wilcoxon matched-pair signed-rank test and intraclass correlation coefficients (ICC). Absolute test-retest reliability was estimated by Bland-Altman analysis. The test-retest amplitude differences for neither of the two measurement techniques were statistically significant as determined by Wilcoxon matched-pair signed-rank test. PT measurements showed greater ICC values than BT amplitude measurements for all test locations. For each measurement technique, the ICC value of the macular response was greater than that of the surrounding locations. The mean test-retest difference was close to zero for both techniques at each of the test locations, and while the coefficient of reliability (COR-1.96 times the standard deviation of the test-retest difference) was comparable for the two techniques at each test location when expressed in nanovolts, the %COR (COR normalized to the mean test and retest amplitudes) was superior for PT than BT measurements. The ICC and COR were comparable for the BT/PT and

Test-retest reliability of the Work Ability Index questionnaire

NARCIS (Netherlands)

de Zwart, B. C. H.; Frings-Dresen, M. H. W.; Van Duivenbooden, J. C.

2002-01-01

The goal of the study was to assess the test-retest reliability of the Work Ability Index (WAI) questionnaire. Reliability was tested using a test-retest design with a 4 week interval between measurements. Valid data were collected among 97 elderly construction workers aged 40 years and older. We

Visual Acuity Testing: Feedback Affects Neither Outcome nor Reproducibility, but Leaves Participants Happier.

Science.gov (United States)

Bach, Michael; Schäfer, Kerstin

2016-01-01

Assessment of visual acuity is a well standardized procedure at least for expert opinions and clinical trials. It is often recommended not giving patients feedback on the correctness of their responses. As this viewpoint has not been quantitatively examined so far, we quantitatively assessed possible effects of feedback on visual acuity testing. In 40 normal participants we presented Landolt Cs in 8 orientations using the automated Freiburg Acuity Test (FrACT, feedback was provided in 2 x 4 conditions: (A) no feedback, (B) acoustic signals indicating correctness, (C)visual indication of correct orientation, and (D) a combination of (B) and (C). After each run the participants judged comfort. Main outcome measures were absolute visual acuity (logMAR), its test-retest agreement (limits of agreement) and participants' comfort estimates on a 5-step symmetric Likert scale. Feedback influenced acuity outcome significantly (p = 0.02), but with a tiny effect size: 0.02 logMAR poorer acuity for (D) compared to (A), even weaker effects for (B) and (C). Test-retest agreement was high (limits of agreement: ± 1.0 lines) and did not depend on feedback (p>0.5). The comfort ranking clearly differed, by 2 steps on the Likert scale: the condition (A)-no feedback-was on average "slightly uncomfortable", the other three conditions were "slightly comfortable" (pFeedback affected neither reproducibility nor the acuity outcome to any relevant extent. The participants, however, reported markedly greater comfort with any kind of feedback. We conclude that systematic feedback (as implemented in FrACT) offers nothing but advantages for routine use.

The role of test-retest reliability in measuring individual and group differences in executive functioning.

Science.gov (United States)

Paap, Kenneth R; Sawi, Oliver

2016-12-01

Studies testing for individual or group differences in executive functioning can be compromised by unknown test-retest reliability. Test-retest reliabilities across an interval of about one week were obtained from performance in the antisaccade, flanker, Simon, and color-shape switching tasks. There is a general trade-off between the greater reliability of single mean RT measures, and the greater process purity of measures based on contrasts between mean RTs in two conditions. The individual differences in RT model recently developed by Miller and Ulrich was used to evaluate the trade-off. Test-retest reliability was statistically significant for 11 of the 12 measures, but was of moderate size, at best, for the difference scores. The test-retest reliabilities for the Simon and flanker interference scores were lower than those for switching costs. Standard practice evaluates the reliability of executive-functioning measures using split-half methods based on data obtained in a single day. Our test-retest measures of reliability are lower, especially for difference scores. These reliability measures must also take into account possible day effects that classical test theory assumes do not occur. Measures based on single mean RTs tend to have acceptable levels of reliability and convergent validity, but are "impure" measures of specific executive functions. The individual differences in RT model shows that the impurity problem is worse than typically assumed. However, the "purer" measures based on difference scores have low convergent validity that is partly caused by deficiencies in test-retest reliability. Copyright © 2016 Elsevier B.V. All rights reserved.

The QUASAR reproducibility study, Part II: Results from a multi center Arterial Spin Labeling test-retest Study

Science.gov (United States)

Petersen, Esben Thade; Mouridsen, Kim; Golay, Xavier

2009-01-01

Arterial Spin Labeling (ASL) is a method to measure perfusion using magnetically labeled blood water as an endogenous tracer. Being fully non-invasive, this technique is attractive for longitudinal studies of cerebral blood flow in healthy and diseased individuals, or as a surrogate marker of metabolism. So far, ASL has been restricted mostly to specialist centers due to a generally low SNR of the method and potential issues with user-dependent analysis needed to obtain quantitative measurement of cerebral blood flow (CBF). Here, we evaluated a particular implementation of ASL (called Quantitative STAR labeling of Arterial Regions or QUASAR), a method providing user independent quantification of CBF in a large test-retest study across sites from around the world, dubbed “The QUASAR reproducibility study”. Altogether, 28 sites located in Asia, Europe and North America participated and a total of 284 healthy volunteers were scanned. Minimal operator dependence was assured by using an automatic planning tool and its accuracy and potential usefulness in multi-center trials was evaluated as well. Accurate repositioning between sessions was achieved with the automatic planning tool showing mean displacements of 1.87±0.95mm and rotations of 1.56±0.66°. Mean gray matter CBF was 47.4±7.5 [ml/100g/min] with a between subject standard variation SDb = 5.5 [ml/100g/min] and a within subject standard deviation SDw = 4.7 [ml/100g/min]. The corresponding repeatability was 13.0 [ml/100g/min] and was found to be within the range of previous studies. PMID:19660557

The QUASAR reproducibility study, Part II: Results from a multi-center Arterial Spin Labeling test-retest study.

Science.gov (United States)

Petersen, Esben Thade; Mouridsen, Kim; Golay, Xavier

2010-01-01

Arterial Spin Labeling (ASL) is a method to measure perfusion using magnetically labeled blood water as an endogenous tracer. Being fully non-invasive, this technique is attractive for longitudinal studies of cerebral blood flow in healthy and diseased individuals, or as a surrogate marker of metabolism. So far, ASL has been restricted mostly to specialist centers due to a generally low SNR of the method and potential issues with user-dependent analysis needed to obtain quantitative measurement of cerebral blood flow (CBF). Here, we evaluated a particular implementation of ASL (called Quantitative STAR labeling of Arterial Regions or QUASAR), a method providing user independent quantification of CBF in a large test-retest study across sites from around the world, dubbed "The QUASAR reproducibility study". Altogether, 28 sites located in Asia, Europe and North America participated and a total of 284 healthy volunteers were scanned. Minimal operator dependence was assured by using an automatic planning tool and its accuracy and potential usefulness in multi-center trials was evaluated as well. Accurate repositioning between sessions was achieved with the automatic planning tool showing mean displacements of 1.87+/-0.95 mm and rotations of 1.56+/-0.66 degrees . Mean gray matter CBF was 47.4+/-7.5 [ml/100 g/min] with a between-subject standard variation SD(b)=5.5 [ml/100 g/min] and a within-subject standard deviation SD(w)=4.7 [ml/100 g/min]. The corresponding repeatability was 13.0 [ml/100 g/min] and was found to be within the range of previous studies.

Long term test-retest reliability of Oswestry Disability Index in male office workers.

Science.gov (United States)

Irmak, Rafet; Baltaci, Gul; Ergun, Nevin

2015-01-01

The Oswestry Disability Index (ODI) is one of the most common condition specific outcome measures used in the management of spinal disorders. But there is insufficient study on healthy populations and long term test-retest reliability. This is important because healthy populations are often used for control groups in low back pain interventions, and knowing the reliability of the controls affects the interpretation of the findings of these studies. The purpose of this study is to determine the long term test-retest reliability of ODI in office workers. Participants who have no chronic low back pain history were included in study. Subjects were assessed by the Turkish-ODI 2.0 (e-forms) on 1st, 2nd, 4th, 8th, 15th, 30th days to determine the stability of ODI scores over time. The study began with 58 (12 female, 46 male) participants. 36 (3 female, 33 male) participated for the full 30 days. Kolmogorov-Smirnov and Friedman tests were used. Test-retest reliability was evaluated by using nonparametric statistics. All tests were done by using SPSS-11. There was no statistically significant difference among the median scores of each day. (χ= 6.482, p >  0.05). The difference between median score of the days with 1st day was neither statistically nor clinically significant. ODI has long term test re-test reliability in healthy subjects over a 1 month time interval.

Test-retest reliability of infant event related potentials evoked by faces.

Science.gov (United States)

Munsters, N M; van Ravenswaaij, H; van den Boomen, C; Kemner, C

2017-04-05

Reliable measures are required to draw meaningful conclusions regarding developmental changes in longitudinal studies. Little is known, however, about the test-retest reliability of face-sensitive event related potentials (ERPs), a frequently used neural measure in infants. The aim of the current study is to investigate the test-retest reliability of ERPs typically evoked by faces in 9-10 month-old infants. The infants (N=31) were presented with neutral, fearful and happy faces that contained only the lower or higher spatial frequency information. They were tested twice within two weeks. The present results show that the test-retest reliability of the face-sensitive ERP components is moderate (P400 and Nc) to substantial (N290). However, there is low test-retest reliability for the effects of the specific experimental manipulations (i.e. emotion and spatial frequency) on the face-sensitive ERPs. To conclude, in infants the face-sensitive ERP components (i.e. N290, P400 and Nc) show adequate test-retest reliability, but not the effects of emotion and spatial frequency on these ERP components. We propose that further research focuses on investigating elements that might increase the test-retest reliability, as adequate test-retest reliability is necessary to draw meaningful conclusions on individual developmental trajectories of the face-sensitive ERPs in infants. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Test-retest reliability of computer-based video analysis of general movements in healthy term-born infants.

Science.gov (United States)

Valle, Susanne Collier; Støen, Ragnhild; Sæther, Rannei; Jensenius, Alexander Refsum; Adde, Lars

2015-10-01

A computer-based video analysis has recently been presented for quantitative assessment of general movements (GMs). This method's test-retest reliability, however, has not yet been evaluated. The aim of the current study was to evaluate the test-retest reliability of computer-based video analysis of GMs, and to explore the association between computer-based video analysis and the temporal organization of fidgety movements (FMs). Test-retest reliability study. 75 healthy, term-born infants were recorded twice the same day during the FMs period using a standardized video set-up. The computer-based movement variables "quantity of motion mean" (Qmean), "quantity of motion standard deviation" (QSD) and "centroid of motion standard deviation" (CSD) were analyzed, reflecting the amount of motion and the variability of the spatial center of motion of the infant, respectively. In addition, the association between the variable CSD and the temporal organization of FMs was explored. Intraclass correlation coefficients (ICC 1.1 and ICC 3.1) were calculated to assess test-retest reliability. The ICC values for the variables CSD, Qmean and QSD were 0.80, 0.80 and 0.86 for ICC (1.1), respectively; and 0.80, 0.86 and 0.90 for ICC (3.1), respectively. There were significantly lower CSD values in the recordings with continual FMs compared to the recordings with intermittent FMs (ptest-retest reliability of computer-based video analysis of GMs, and a significant association between our computer-based video analysis and the temporal organization of FMs. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Psychometric Evaluation of the Brachial Assessment Tool Part 1: Reproducibility.

Science.gov (United States)

Hill, Bridget; Williams, Gavin; Olver, John; Ferris, Scott; Bialocerkowski, Andrea

2018-04-01

To evaluate reproducibility (reliability and agreement) of the Brachial Assessment Tool (BrAT), a new patient-reported outcome measure for adults with traumatic brachial plexus injury (BPI). Prospective repeated-measure design. Outpatient clinics. Adults with confirmed traumatic BPI (N=43; age range, 19-82y). People with BPI completed the 31-item 4-response BrAT twice, 2 weeks apart. Results for the 3 subscales and summed score were compared at time 1 and time 2 to determine reliability, including systematic differences using paired t tests, test retest using intraclass correlation coefficient model 1,1 (ICC 1,1 ), and internal consistency using Cronbach α. Agreement parameters included standard error of measurement, minimal detectable change, and limits of agreement. BrAT. Test-retest reliability was excellent (ICC 1,1 =.90-.97). Internal consistency was high (Cronbach α=.90-.98). Measurement error was relatively low (standard error of measurement range, 3.1-8.8). A change of >4 for subscale 1, >6 for subscale 2, >4 for subscale 3, and >10 for the summed score is indicative of change over and above measurement error. Limits of agreement ranged from ±4.4 (subscale 3) to 11.61 (summed score). These findings support the use of the BrAT as a reproducible patient-reported outcome measure for adults with traumatic BPI with evidence of appropriate reliability and agreement for both individual and group comparisons. Further psychometric testing is required to establish the construct validity and responsiveness of the BrAT. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Preclinical evaluation and test-retest studies of [{sup 18}F]PSS232, a novel radioligand for targeting metabotropic glutamate receptor 5 (mGlu{sub 5})

Energy Technology Data Exchange (ETDEWEB)

Milicevic Sephton, Selena; Mueller Herde, Adrienne; Keller, Claudia; Ruedisuehli, Sonja; Schibli, Roger; Kraemer, Stefanie D.; Ametamey, Simon M. [Center for Radiopharmaceutical Sciences of ETH, PSI and USZ, Zurich (Switzerland); Mu, Linjing [University Hospital Zuerich, Department of Nuclear Medicine, Zuerich (Switzerland); Auberson, Yves [Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel (Switzerland)

2015-01-15

A novel, {sup 18}F-labelled metabotropic glutamate receptor subtype 5 (mGlu{sub 5}) derivative of [{sup 11}C]ABP688 ([{sup 11}C]1), [{sup 18}F]PSS232 ([{sup 18}F]5), was evaluated in vitro and in vivo for its potential as a PET agent and was used in test-retest reliability studies The radiosynthesis of [{sup 18}F]5 was accomplished via a one-step reaction using a mesylate precursor. In vitro stability was determined in PBS and plasma, and with liver microsomal enzymes. Metabolite studies were performed using rat brain extracts, blood and urine. In vitro autoradiography was performed on horizontal slices of rat brain using 1 and 8, antagonists for mGlu{sub 5} and mGlu{sub 1}, respectively. Small-animal PET, biodistribution, and test-retest studies were performed in Wistar rats. In vivo, dose-dependent displacement studies were performed using 6 and blocking studies with 7. [{sup 18}F]5 was obtained in decay-corrected maximal radiochemical yield of 37 % with a specific activity of 80 - 400 GBq/μmol. Treatment with rat and human microsomal enzymes in vitro for 60 min resulted in 20 % and 4 % of hydrophilic radiometabolites, respectively. No hydrophilic decomposition products or radiometabolites were found in PBS or plasma. In vitro autoradiography on rat brain slices showed a heterogeneous distribution consistent with the known distribution of mGlu{sub 5} with high binding to hippocampal and cortical regions, and negligible radioactivity in the cerebellum. Similar distribution of radioactivity was found in PET images. Under displacement conditions with 6, reduced [{sup 18}F]5 binding was found in all brain regions except the cerebellum. 7 reduced binding in the striatum by 84 % on average. Test-retest studies were reproducible with a variability ranging from 6.8 % to 8.2 %. An extended single-dose toxicity study in Wistar rats showed no compound-related adverse effects. The new mGlu{sub 5} radiotracer, [{sup 18}F]5, showed specific and selective in vitro and in vivo

Estimation of macular pigment optical density in the elderly: test-retest variability and effect of optical blur in pseudophakic subjects

NARCIS (Netherlands)

Gallaher, Kevin T.; Mura, Marco; Todd, Wm Andrew; Harris, Tarsha L.; Kenyon, Emily; Harris, Tamara; Johnson, Karen C.; Satterfield, Suzanne; Kritchevsky, Stephen B.; Iannaccone, Alessandro

2007-01-01

The reproducibility of macular pigment optical density (MPOD) estimates in the elderly was assessed in 40 subjects (age: 79.1+/-3.5). Test-retest variability was good (Pearson's r coefficient: 0.734), with an average coefficient of variation (CV) of 18.4% and an intraclass correlation coefficient

Minimum joint space width (mJSW) of patellofemoral joint on standing ''skyline'' radiographs: test-retest reproducibility and comparison with quantitative magnetic resonance imaging (qMRI)

Energy Technology Data Exchange (ETDEWEB)

Simoni, Paolo; Jamali, Sanaa; Alvarez Miezentseva, Victoria [CHU de Liege, Diagnostic Imaging Departement, Domanine du Sart Tilman, Liege (Belgium); Albert, Adelin [CHU de Liege, Biostatistics Departement, Domanine du Sart Tilman, Liege (Belgium); Totterman, Saara; Schreyer, Edward; Tamez-Pena, Jose G. [Qmetrics Technologies, Rochester, NY (United States); Zobel, Bruno Beomonte [Campus Bio-Medico University, Diagnostic Imaging Departement, Rome (Italy); Gillet, Philippe [CHU de Liege, Orthopaedic surgery Department, Domanine du Sart Tilman, Liege (Belgium)

2013-11-15

To assess the intraobserver, interobserver, and test-retest reproducibility of minimum joint space width (mJSW) measurement of medial and lateral patellofemoral joints on standing ''skyline'' radiographs and to compare the mJSW of the patellofemoral joint to the mean cartilage thickness calculated by quantitative magnetic resonance imaging (qMRI). A couple of standing ''skyline'' radiographs of the patellofemoral joints and MRI of 55 knees of 28 volunteers (18 females, ten males, mean age, 48.5 {+-} 16.2 years) were obtained on the same day. The mJSW of the patellofemoral joint was manually measured and Kellgren and Lawrence grade (KLG) was independently assessed by two observers. The mJSW was compared to the mean cartilage thickness of patellofemoral joint calculated by qMRI. mJSW of the medial and lateral patellofemoral joint showed an excellent intraobserver agreement (interclass correlation (ICC) = 0.94 and 0.96), interobserver agreement (ICC = 0.90 and 0.95) and test-retest agreement (ICC = 0.92 and 0.96). The mJSW measured on radiographs was correlated to mean cartilage thickness calculated by qMRI (r = 0.71, p < 0.0001 for the medial PFJ and r = 0.81, p < 0.0001 for the lateral PFJ). However, there was a lack of concordance between radiographs and qMRI for extreme values of joint width and KLG. Radiographs yielded higher joint space measures than qMRI in knees with a normal joint space, while qMRI yielded higher joint space measures than radiographs in knees with joint space narrowing and higher KLG. Standing ''skyline'' radiographs are a reproducible tool for measuring the mJSW of the patellofemoral joint. The mJSW of the patellofemoral joint on radiographs are correlated with, but not concordant with, qMRI measurements. (orig.)

Test-Retest Reliability of the Short-Form Survivor Unmet Needs Survey.

Science.gov (United States)

Taylor, Karen; Bulsara, Max; Monterosso, Leanne

2018-01-01

Reliable and valid needs assessment measures are important assessment tools in cancer survivorship care. A new 30-item short-form version of the Survivor Unmet Needs Survey (SF-SUNS) was developed and validated with cancer survivors, including hematology cancer survivors; however, test-retest reliability has not been established. The objective of this study was to assess the test-retest reliability of the SF-SUNS with a cohort of lymphoma survivors ( n = 40). Test-retest reliability of the SF-SUNS was conducted at two time points: baseline (time 1) and 5 days later (time 2). Test-retest data were collected from lymphoma cancer survivors ( n = 40) in a large tertiary cancer center in Western Australia. Intraclass correlation analyses compared data at time 1 (baseline) and time 2 (5 days later). Cronbach's alpha analyses were performed to assess the internal consistency at both time points. The majority (23/30, 77%) of items achieved test-retest reliability scores 0.45-0.74 (fair to good). A high degree of overall internal consistency was demonstrated (time 1 = 0.92, time 2 = 0.95), with scores 0.65-0.94 across subscales for both time points. Mixed test-retest reliability of the SF-SUNS was established. Our results indicate the SF-SUNS is responsive to the changing needs of lymphoma cancer survivors. Routine use of cancer survivorship specific needs-based assessments is required in oncology care today. Nurses are well placed to administer these assessments and provide tailored information and resources. Further assessment of test-retest reliability in hematology and other cancer cohorts is warranted.

Resting-state test-retest reliability of a priori defined canonical networks over different preprocessing steps.

Science.gov (United States)

Varikuti, Deepthi P; Hoffstaedter, Felix; Genon, Sarah; Schwender, Holger; Reid, Andrew T; Eickhoff, Simon B

2017-04-01

Resting-state functional connectivity analysis has become a widely used method for the investigation of human brain connectivity and pathology. The measurement of neuronal activity by functional MRI, however, is impeded by various nuisance signals that reduce the stability of functional connectivity. Several methods exist to address this predicament, but little consensus has yet been reached on the most appropriate approach. Given the crucial importance of reliability for the development of clinical applications, we here investigated the effect of various confound removal approaches on the test-retest reliability of functional-connectivity estimates in two previously defined functional brain networks. Our results showed that gray matter masking improved the reliability of connectivity estimates, whereas denoising based on principal components analysis reduced it. We additionally observed that refraining from using any correction for global signals provided the best test-retest reliability, but failed to reproduce anti-correlations between what have been previously described as antagonistic networks. This suggests that improved reliability can come at the expense of potentially poorer biological validity. Consistent with this, we observed that reliability was proportional to the retained variance, which presumably included structured noise, such as reliable nuisance signals (for instance, noise induced by cardiac processes). We conclude that compromises are necessary between maximizing test-retest reliability and removing variance that may be attributable to non-neuronal sources.

Resting-state test-retest reliability of a priori defined canonical networks over different preprocessing steps

Science.gov (United States)

Varikuti, Deepthi P.; Hoffstaedter, Felix; Genon, Sarah; Schwender, Holger; Reid, Andrew T.; Eickhoff, Simon B.

2016-01-01

Resting-state functional connectivity analysis has become a widely used method for the investigation of human brain connectivity and pathology. The measurement of neuronal activity by functional MRI, however, is impeded by various nuisance signals that reduce the stability of functional connectivity. Several methods exist to address this predicament, but little consensus has yet been reached on the most appropriate approach. Given the crucial importance of reliability for the development of clinical applications, we here investigated the effect of various confound removal approaches on the test-retest reliability of functional-connectivity estimates in two previously defined functional brain networks. Our results showed that grey matter masking improved the reliability of connectivity estimates, whereas de-noising based on principal components analysis reduced it. We additionally observed that refraining from using any correction for global signals provided the best test-retest reliability, but failed to reproduce anti-correlations between what have been previously described as antagonistic networks. This suggests that improved reliability can come at the expense of potentially poorer biological validity. Consistent with this, we observed that reliability was proportional to the retained variance, which presumably included structured noise, such as reliable nuisance signals (for instance, noise induced by cardiac processes). We conclude that compromises are necessary between maximizing test-retest reliability and removing variance that may be attributable to non-neuronal sources. PMID:27550015

Significant decreases in frontal and temporal [11C]-raclopride binding after THC challenge.

Science.gov (United States)

Stokes, Paul R A; Egerton, Alice; Watson, Ben; Reid, Alistair; Breen, Gerome; Lingford-Hughes, Anne; Nutt, David J; Mehta, Mitul A

2010-10-01

Delta9-tetrahydrocannabinol (THC) increases prefrontal cortical dopamine release in animals, but this is yet to be examined in humans. In man, striatal dopamine release can be indexed using [11C]-raclopride positron emission tomography (PET), and recent reports suggest that cortical [11C]-raclopride binding may also be sensitive to dopaminergic challenges. Using an existing dataset we examined whether THC alters [11C]-raclopride binding potential (BP(ND)) in cortical regions. Thirteen healthy volunteers underwent two [11C]-raclopride PET scans following either oral 10 mg THC or placebo. Significant areas of decreased cortical [11C]-raclopride BP(ND) were identified using whole brain voxel-wise analysis and quantified using a region of interest (ROI) ratio analysis. Effect of blood flow on binding was estimated using a simplified reference tissue model analysis. Results were compared to [11C]-raclopride test-retest reliability in the ROIs identified using a separate cohort of volunteers. Voxel-wise analysis identified three significant clusters of decreased [11C]-raclopride BP(ND) after THC in the right middle frontal gyrus, left superior frontal gyrus and left superior temporal gyrus. Decreases in [11C]-raclopride BPND following THC were greater than test-retest variability in these ROIs. R1, an estimate of blood flow, significantly decreased in the left superior frontal gyrus in the THC condition but was unchanged in the other ROIs. Decreased frontal binding significantly correlated to catechol-o-methyl transferase (COMT) val108 status. We have demonstrated for the first time significant decreases in bilateral frontopolar cortical and left superior temporal gyrus [11C]-raclopride binding after THC. The interpretation of these findings in relation to prefrontal dopamine release is discussed. Copyright 2010 Elsevier Inc. All rights reserved.

Normal ranges and test-retest reproducibility of flow and velocity parameters in intracranial arteries measured with phase-contrast magnetic resonance imaging

International Nuclear Information System (INIS)

Correia de Verdier, Maria; Wikstroem, Johan

2016-01-01

The purpose of the present study was to investigate normal ranges and test-retest reproducibility of phase-contrast MRI (PC-MRI)-measured flow and velocity parameters in intracranial arteries. Highest flow (HF), lowest flow (LF), peak systolic velocity (PSV), and end diastolic velocity (EDV) were measured at two dates in the anterior (ACA), middle (MCA), and posterior (PCA) cerebral arteries of 30 healthy volunteers using two-dimensional PC-MRI at 3 T. Least detectable difference (LDD) was calculated. In the left ACA, HF was (mean (range, LDD)) 126 ml/min (36-312, 59 %), LF 61 ml/min (0-156, 101 %), PSV 64 cm/s (32-141, 67 %), and EDV 35 cm/s (18-55, 42 %); in the right ACA, HF was 154 ml/min (42-246, 49 %), LF 77 ml/min (0-156, 131 %), PSV 75 cm/s (26-161, 82 %), and EDV 39 cm/s (7-59, 67 %). In the left MCA, HF was 235 ml/min (126-372, 35 %), LF 116 ml/min (42-186, 48 %), PSV 90 cm/s (55-183, 39 %), and EDV 46 cm/s (20-66, 28 %); in the right MCA, HF was 238 ml/min (162-342, 44 %), LF 120 ml/min (72-216, 48 %), PSV 88 cm/s (55-141, 35 %), and EDV 45 cm/s (26-67, 23 %). In the left PCA, HF was 108 ml/min (42-168, 54 %), LF 53 ml/min (18-108, 64 %), PSV 50 cm/s (24-77, 63 %), and EDV 28 cm/s (14-40, 45 %); in the right PCA, HF was 98 ml/min (30-162, 49 %), LF 49 ml/min (12-84, 55 %), PSV 47 cm/s (27-88, 59 %), and EDV 27 cm/s (16-41, 45 %). PC-MRI-measured flow and velocity parameters in the main intracranial arteries have large normal ranges. Reproducibility is highest in MCA. (orig.)

Normal ranges and test-retest reproducibility of flow and velocity parameters in intracranial arteries measured with phase-contrast magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Correia de Verdier, Maria; Wikstroem, Johan [Uppsala University Hospital, Department of Radiology, Uppsala University, Uppsala (Sweden)

2016-05-15

The purpose of the present study was to investigate normal ranges and test-retest reproducibility of phase-contrast MRI (PC-MRI)-measured flow and velocity parameters in intracranial arteries. Highest flow (HF), lowest flow (LF), peak systolic velocity (PSV), and end diastolic velocity (EDV) were measured at two dates in the anterior (ACA), middle (MCA), and posterior (PCA) cerebral arteries of 30 healthy volunteers using two-dimensional PC-MRI at 3 T. Least detectable difference (LDD) was calculated. In the left ACA, HF was (mean (range, LDD)) 126 ml/min (36-312, 59 %), LF 61 ml/min (0-156, 101 %), PSV 64 cm/s (32-141, 67 %), and EDV 35 cm/s (18-55, 42 %); in the right ACA, HF was 154 ml/min (42-246, 49 %), LF 77 ml/min (0-156, 131 %), PSV 75 cm/s (26-161, 82 %), and EDV 39 cm/s (7-59, 67 %). In the left MCA, HF was 235 ml/min (126-372, 35 %), LF 116 ml/min (42-186, 48 %), PSV 90 cm/s (55-183, 39 %), and EDV 46 cm/s (20-66, 28 %); in the right MCA, HF was 238 ml/min (162-342, 44 %), LF 120 ml/min (72-216, 48 %), PSV 88 cm/s (55-141, 35 %), and EDV 45 cm/s (26-67, 23 %). In the left PCA, HF was 108 ml/min (42-168, 54 %), LF 53 ml/min (18-108, 64 %), PSV 50 cm/s (24-77, 63 %), and EDV 28 cm/s (14-40, 45 %); in the right PCA, HF was 98 ml/min (30-162, 49 %), LF 49 ml/min (12-84, 55 %), PSV 47 cm/s (27-88, 59 %), and EDV 27 cm/s (16-41, 45 %). PC-MRI-measured flow and velocity parameters in the main intracranial arteries have large normal ranges. Reproducibility is highest in MCA. (orig.)

Synthesis and pharmacological characterization of a new PET ligand for the serotonin transporter: [{sup 11}C]5-bromo-2-[2-(dimethylaminomethylphenylsulfanyl)]phenylamine ([{sup 11}C]DAPA)

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Huang Yiyun E-mail: hh285@columbia.edu; Hwang, D.-R.; Zhu Zhihong; Bae, S.-A.; Guo Ningning; Sudo, Yasuhiko; Kegeles, Lawrence S.; Laruelle, Marc

2002-10-01

A new PET radioligand for the serotonin transporter (SERT), [{sup 11}C]-5-bromo-2-[2-(dimethylaminomethylphenylsulfanyl)]phenylamine ([{sup 11}C]DAPA (10), was synthesized and evaluated in vivo in rats and baboons. [{sup 11}C]DAPA (10) was prepared from its monomethylamino precursor 8 by reaction with high specific activity [{sup 11}C]methyl iodide. Radiochemical yield was 24{+-}5% based on [{sup 11}C]methyl iodide at end of bombardment (EOB, n=10) and specific activity was 1553{+-}939 Ci/mmol at end of synthesis (EOS, n=10). Binding assays indicated that [{sup 11}C]DAPA displays high affinity (Ki 1.49{+-}0.28 nM for hSERT) and good selectivity for the SERT in vitro. Biodistribution studies in rats indicated that [{sup 11}C]DAPA enters into the brain readily and localizes in brain regions known to contain high concentrations of SERT, such as the thalamus, hypothalamus, frontal cortex and striatum. Moreover, such binding in SERT-rich regions of the brain are blocked by pretreatment with either the selective serotonin reuptake inhibitor (SSRI) citalopram and by the cold compound itself, demonstrating that [{sup 11}C]DAPA binding in the rat brain is saturable and specific to SERT. Imaging experiments in baboons indicated that [{sup 11}C]DAPA binding is consistent with the known distribution of SERT in the baboon brain, with highest levels of radioactivity detected in the midbrain and thalamus, intermediate levels in the hippocampus and striatum, and lower levels in the cortical regions. Pretreatment of the baboon with citalopram 10 min before radioactivity injection blocked the binding of [{sup 11}C]DAPA in all brain regions that contain SERT. Kinetic analysis revealed that, in all brain regions examined, [{sup 11}C]DAPA specific to nonspecific distribution volume ratios (V{sub 3}'') are higher than [{sup 11}C](+)-McN 5652 and similar to [{sup 11}C]DASB. In summary, [{sup 11}C]DAPA appears to be a promising radioligand suitable for the visualization of SERT

Balance Assessment in Sports-Related Concussion: Evaluating Test-Retest Reliability of the Equilibrate System.

Science.gov (United States)

Odom, Mitchell J; Lee, Young M; Zuckerman, Scott L; Apple, Rachel P; Germanos, Theodore; Solomon, Gary S; Sills, Allen K

2016-01-01

This study evaluated the test-retest reliability of a novel computer-based, portable balance assessment tool, the Equilibrate System (ES), used to diagnose sports-related concussion. Twenty-seven students participated in ES testing consisting of three sessions over 4 weeks. The modified Balance Error Scoring System was performed. For each participant, test-retest reliability was established using the intraclass correlation coefficient (ICC). The ES test-retest reliability from baseline to week 2 produced an ICC value of 0.495 (95% CI, 0.123-0.745). Week 2 testing produced ICC values of 0.602 (95% CI, 0.279-0.803) and 0.610 (95% CI, 0.299-0.804), respectively. All other single measures test-retest reliability values produced poor ICC values. Same-day ES testing showed fair to good test-retest reliability while interweek measures displayed poor to fair test-retest reliability. Testing conditions should be controlled when using computerized balance assessment methods. ES testing should only be used as a part of a comprehensive assessment.

Diffusion-weighted (DW) MRI in lung cancers. ADC test-retest repeatability

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Weller, Alex; Papoutsaki, Marianthi Vasiliki; Blackledge, Matthew; DeSouza, Nandita M. [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, CRUK Cancer Imaging Centre, Surrey (United Kingdom); Waterton, John C. [University of Manchester, Manchester (United Kingdom); Chiti, Arturo [Humanitas University, Milan (Italy); Stroobants, Sigrid [Universiteit Antwerpen, Antwerpen (Belgium); Kuijer, Joost [Vrije Universiteit Medisch Centrum, Amsterdam (Netherlands); Morgan, Veronica [Royal Marsden NHS Foundation Trust, Department of Medicine, London (United Kingdom)

2017-11-15

To determine the test-retest repeatability of Apparent Diffusion Coefficient (ADC) measurements across institutions and MRI vendors, plus investigate the effect of post-processing methodology on measurement precision. Thirty malignant lung lesions >2 cm in size (23 patients) were scanned on two occasions, using echo-planar-Diffusion-Weighted (DW)-MRI to derive whole-tumour ADC (b = 100, 500 and 800 s/mm{sup -2}). Scanning was performed at 4 institutions (3 MRI vendors). Whole-tumour volumes-of-interest were copied from first visit onto second visit images and from one post-processing platform to an open-source platform, to assess ADC repeatability and cross-platform reproducibility. Whole-tumour ADC values ranged from 0.66-1.94x10{sup -3} mm{sup 2}s{sup -1} (mean = 1.14). Within-patient coefficient-of-variation (wCV) was 7.1% (95% CI 5.7-9.6%), limits-of-agreement (LoA) -18.0 to 21.9%. Lesions >3 cm had improved repeatability: wCV 3.9% (95% CI 2.9-5.9%); and LoA -10.2 to 11.4%. Variability for lesions <3 cm was 2.46 times higher. ADC reproducibility across different post-processing platforms was excellent: Pearson's R{sup 2} = 0.99; CoV 2.8% (95% CI 2.3-3.4%); and LoA -7.4 to 8.0%. A free-breathing DW-MRI protocol for imaging malignant lung tumours achieved satisfactory within-patient repeatability and was robust to changes in post-processing software, justifying its use in multi-centre trials. For response evaluation in individual patients, a change in ADC >21.9% will reflect treatment-related change. (orig.)

Evaluating test-retest reliability in patient-reported outcome measures for older people: A systematic review.

Science.gov (United States)

Park, Myung Sook; Kang, Kyung Ja; Jang, Sun Joo; Lee, Joo Yun; Chang, Sun Ju

2018-03-01

This study aimed to evaluate the components of test-retest reliability including time interval, sample size, and statistical methods used in patient-reported outcome measures in older people and to provide suggestions on the methodology for calculating test-retest reliability for patient-reported outcomes in older people. This was a systematic literature review. MEDLINE, Embase, CINAHL, and PsycINFO were searched from January 1, 2000 to August 10, 2017 by an information specialist. This systematic review was guided by both the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist and the guideline for systematic review published by the National Evidence-based Healthcare Collaborating Agency in Korea. The methodological quality was assessed by the Consensus-based Standards for the selection of health Measurement Instruments checklist box B. Ninety-five out of 12,641 studies were selected for the analysis. The median time interval for test-retest reliability was 14days, and the ratio of sample size for test-retest reliability to the number of items in each measure ranged from 1:1 to 1:4. The most frequently used statistical methods for continuous scores was intraclass correlation coefficients (ICCs). Among the 63 studies that used ICCs, 21 studies presented models for ICC calculations and 30 studies reported 95% confidence intervals of the ICCs. Additional analyses using 17 studies that reported a strong ICC (>0.09) showed that the mean time interval was 12.88days and the mean ratio of the number of items to sample size was 1:5.37. When researchers plan to assess the test-retest reliability of patient-reported outcome measures for older people, they need to consider an adequate time interval of approximately 13days and the sample size of about 5 times the number of items. Particularly, statistical methods should not only be selected based on the types of scores of the patient-reported outcome measures, but should also be described clearly in

Acoustic stapedial reflexes in healthy neonates: normative data and test-retest reliability.

Science.gov (United States)

Kei, Joseph

2012-01-01

The acoustic stapedial reflex (ASR) test provides useful information about the function of the auditory system. While it is frequently used with adults and children in a clinical setting, its use with young infants is limited. Presently, there are few data for neonates and inadequate research into the test-retest reliability of the ASR test. This study aimed to establish normative data and evaluate the test-retest reliability of the ASR test in healthy neonates. A cross-sectional experimental design was used to establish ASR normative data and assess the test-retest reliability of ASR thresholds obtained from healthy neonates. Sixty-eight full-term neonates with mean chronological age of 2.5 days (SD = 1.8 day), who passed the automated auditory brainstem response, transient evoked otoacoustic emission, and high frequency (1 kHz) tympanometry (HFT) tests. One randomly selected ear from each neonate was tested using TEOAE (transient evoked otoacoustic emission), HFT, and ASR tests using a 1 kHz probe tone. ASR thresholds were elicited by presenting pure tones of 0.5, 2, and 4 kHz and broadband noise (BBN) separately to the test ear in an ipsilateral stimulation mode. The ASR procedure was repeated to acquire retest data within the same testing session. Descriptive statistics, χ2, and analysis of variance with repeated measures tests were used to analyze ASR data. All neonates exhibited ASR when stimulated by tonal stimuli or BBN. The mean ASRTs (acoustic stapedial reflex thresholds) for the 0.5, 2, and 4 kHz tones were 81.6 ± 7.9, 71.3 ± 7.9, and 65.4 ± 8.7 dB HL, respectively. The mean ASRT for the BBN was estimated to be smaller than 57.2 dB HL, given the limitation of the equipment. The 95th percentiles of the ASRT were 95, 85, 80, and 75 dB HL for the 0.5, 2, and 4 kHz and BBN, respectively. The test-retest reliability of the ASR test for all stimuli was high, with no significant difference in mean ASRTs across the test and retest conditions. Test-retest

Morpho-Functional 1H-MRI of the Lung in COPD: Short-Term Test-Retest Reliability.

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Bertram J Jobst

Full Text Available Non-invasive end-points for interventional trials and tailored treatment regimes in chronic obstructive pulmonary disease (COPD for monitoring regionally different manifestations of lung disease instead of global assessment of lung function with spirometry would be valuable. Proton nuclear magnetic resonance imaging (1H-MRI allows for a radiation-free assessment of regional structure and function. The aim of this study was to evaluate the short-term reproducibility of a comprehensive morpho-functional lung MRI protocol in COPD.20 prospectively enrolled COPD patients (GOLD I-IV underwent 1H-MRI of the lung at 1.5T on two consecutive days, including sequences for morphology, 4D contrast-enhanced perfusion, and respiratory mechanics. Image quality and COPD-related morphological and functional changes were evaluated in consensus by three chest radiologists using a dedicated MRI-based visual scoring system. Test-retest reliability was calculated per each individual lung lobe for the extent of large airway (bronchiectasis, wall thickening, mucus plugging and small airway abnormalities (tree in bud, peripheral bronchiectasis, mucus plugging, consolidations, nodules, parenchymal defects and perfusion defects. The presence of tracheal narrowing, dystelectasis, pleural effusion, pulmonary trunk ectasia, right ventricular enlargement and, finally, motion patterns of diaphragma and chest wall were addressed.Median global scores [10(Q1:8.00;Q3:16.00 vs.11(Q1:6.00;Q3:15.00] as well as category subscores were similar between both timepoints, and kappa statistics indicated "almost perfect" global agreement (ĸ = 0.86, 95%CI = 0.81-0.91. Most subscores showed at least "substantial" agreement of MRI1 and MRI2 (ĸ = 0.64-1.00, whereas the agreement for the diagnosis of dystelectasis/effusion (ĸ = 0.42, 95%CI = 0.00-0.93 was "moderate" and of tracheal abnormalities (ĸ = 0.21, 95%CI = 0.00-0.75 "fair". Most MRI acquisitions showed at least diagnostic quality at

Test-retest reliability and smallest detectable change of the Bristol Impact of Hypermobility (BIoH) questionnaire.

Science.gov (United States)

Palmer, S; Manns, S; Cramp, F; Lewis, R; Clark, E M

2017-12-01

The Bristol Impact of Hypermobility (BIoH) questionnaire is a patient-reported outcome measure developed in conjunction with adults with Joint Hypermobility Syndrome (JHS). It has demonstrated strong concurrent validity with the Short Form-36 (SF-36) physical component score but other psychometric properties have yet to be established. This study aimed to determine its test-retest reliability and smallest detectable change (SDC). A test-retest reliability study. Participants were recruited from the Hypermobility Syndromes Association, a patient organisation in the United Kingdom. Recruitment packs were sent to 1080 adults who had given permission to be contacted about research. BIoH and SF-36 questionnaires were administered at baseline and repeated two weeks later. An 11-point global rating of change scale (-5 to +5) was also administered at two weeks. Test-retest analysis and calculation of the SDC was conducted on 'stable' patients (defined as global rating of change -1 to +1). 462 responses were received. 233 patients reported a 'stable' condition and were included in analysis (95% women; mean (SD) age 44.5 (13.9) years; BIoH score 223.6 (54.0)). The BIoH questionnaire demonstrated excellent test-retest reliability (ICC 0.923, 95% CI 0.900-0.940). The SDC was 42 points (equivalent to 19% of the mean baseline score). The SF-36 physical and mental component scores demonstrated poorer test-retest reliability and larger SDCs (as a proportion of the mean baseline scores). The results provide further evidence of the potential of the BIoH questionnaire to underpin research and clinical practice for people with JHS. Copyright © 2017 Elsevier Ltd. All rights reserved.

Does an eye-hand coordination test have added value as part of talent identification in table tennis? A validity and reproducibility study.

Science.gov (United States)

Faber, Irene R; Oosterveld, Frits G J; Nijhuis-Van der Sanden, Maria W G

2014-01-01

This study investigated the added value, i.e. discriminative and concurrent validity and reproducibility, of an eye-hand coordination test relevant to table tennis as part of talent identification. Forty-three table tennis players (7-12 years) from national (n = 13), regional (n = 11) and local training centres (n = 19) participated. During the eye-hand coordination test, children needed to throw a ball against a vertical positioned table tennis table with one hand and to catch the ball correctly with the other hand as frequently as possible in 30 seconds. Four different test versions were assessed varying the distance to the table (1 or 2 meter) and using a tennis or table tennis ball. 'Within session' reproducibility was estimated for the two attempts of the initial tests and ten youngsters were retested after 4 weeks to estimate 'between sessions' reproducibility. Validity analyses using age as covariate showed that players from the national and regional centres scored significantly higher than players from the local centre in all test versions (ptalent identification appears to be the version with a table tennis ball at 1 meter regarding the psychometric characteristics evaluated. Longitudinal studies are necessary to evaluate the predictive value of this test.

Establishing the Test-Retest Reliability & Concurrent Validity for the Repeat Ice Skating Test (RIST) in Adolescent Male Ice Hockey Players

Science.gov (United States)

Power, Allan; Faught, Brent E.; Przysucha, Eryk; McPherson, Moira; Montelpare, William

2012-01-01

In this study the authors examine the test-retest reliability and concurrent validity of the Repeat Ice Skating Test (RIST). This was an on-ice field anaerobic test that measured average peak power and was validated with 3 anaerobic lab tests: (a) vertical jump, (b) the Margaria-Kalamen stair test, and (c) the Wingate Anaerobic Test. The…

Investigating univariate temporal patterns for intrinsic connectivity networks based on complexity and low-frequency oscillation: a test-retest reliability study.

Science.gov (United States)

Wang, X; Jiao, Y; Tang, T; Wang, H; Lu, Z

2013-12-19

Intrinsic connectivity networks (ICNs) are composed of spatial components and time courses. The spatial components of ICNs were discovered with moderate-to-high reliability. So far as we know, few studies focused on the reliability of the temporal patterns for ICNs based their individual time courses. The goals of this study were twofold: to investigate the test-retest reliability of temporal patterns for ICNs, and to analyze these informative univariate metrics. Additionally, a correlation analysis was performed to enhance interpretability. Our study included three datasets: (a) short- and long-term scans, (b) multi-band echo-planar imaging (mEPI), and (c) eyes open or closed. Using dual regression, we obtained the time courses of ICNs for each subject. To produce temporal patterns for ICNs, we applied two categories of univariate metrics: network-wise complexity and network-wise low-frequency oscillation. Furthermore, we validated the test-retest reliability for each metric. The network-wise temporal patterns for most ICNs (especially for default mode network, DMN) exhibited moderate-to-high reliability and reproducibility under different scan conditions. Network-wise complexity for DMN exhibited fair reliability (ICC<0.5) based on eyes-closed sessions. Specially, our results supported that mEPI could be a useful method with high reliability and reproducibility. In addition, these temporal patterns were with physiological meanings, and certain temporal patterns were correlated to the node strength of the corresponding ICN. Overall, network-wise temporal patterns of ICNs were reliable and informative and could be complementary to spatial patterns of ICNs for further study. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

Imaging of the brain serotonin transporters (SERT) with {sup 18}F-labelled fluoromethyl-McN5652 and PET in humans

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Hesse, Swen [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Leipzig University Medical Center, AdiposityDiseases, Leipzig (Germany); Brust, Peter [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmacy, Research Site Leipzig, Leipzig (Germany); Maeding, Peter; Zessin, Joerg; Fuechtner, Frank [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmacy, Dresden (Germany); Becker, Georg-Alexander; Patt, Marianne; Seese, Anita; Sorger, Dietlind; Meyer, Philipp M.; Habermann, Bernd; Luthardt, Julia; Bresch, Anke; Sabri, Osama [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Lobsien, Donald [University of Leipzig, Department of Neuroradiology, Leipzig (Germany); Laudi, Sven [University of Leipzig, Department of Anaesthesiology and Intensive Care, Leipzig (Germany); Steinbach, Joerg [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmacy, Dresden (Germany); Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmacy, Research Site Leipzig, Leipzig (Germany)

2012-06-15

[{sup 11}C]DASB is currently the most frequently used highly selective radiotracer for visualization and quantification of central SERT. Its use, however, is hampered by the short half-life of {sup 11}C, the moderate cortical test-retest reliability, and the lack of quantifying endogenous serotonin. Labelling with {sup 18}F allows in principle longer acquisition times for kinetic analysis in brain tissue and may provide higher sensitivity. The aim of our study was to firstly use the new highly SERT-selective {sup 18}F-labelled fluoromethyl analogue of (+)-McN5652 ((+)-[{sup 18}F]FMe-McN5652) in humans and to evaluate its potential for SERT quantification. The PET data from five healthy volunteers (three men, two women, age 39 {+-} 10 years) coregistered with individual MRI scans were semiquantitatively assessed by volume-of-interest analysis using the software package PMOD. Rate constants and total distribution volumes (V{sub T}) were calculated using a two-tissue compartment model and arterial input function measurements were corrected for metabolite/plasma data. Standardized uptake region-to-cerebellum ratios as a measure of specific radiotracer accumulation were compared with those of a [{sup 11}C]DASB PET dataset from 21 healthy subjects (10 men, 11 women, age 38 {+-} 8 years). The two-tissue compartment model provided adequate fits to the data. Estimates of total distribution volume (V{sub T}) demonstrated good identifiability based on the coefficients of variation (COV) for the volumes of interest in SERT-rich and cortical areas (COV V{sub T} <10%). Compared with [{sup 11}C]DASB PET, there was a tendency to lower mean uptake values in (+)-[{sup 18}F]FMe-McN5652 PET; however, the standard deviation was also somewhat lower. Altogether, cerebral (+)-[{sup 18}F]FMe-McN5652 uptake corresponded well with the known SERT distribution in humans. The results showed that (+)-[{sup 18}F]FMe-McN5652 is also suitable for in vivo quantification of SERT with PET. Because of

Interrater and Test-Retest Reliability and Minimal Detectable Change of the Balance Evaluation Systems Test (BESTest) and Subsystems With Community-Dwelling Older Adults.

Science.gov (United States)

Wang-Hsu, Elizabeth; Smith, Susan S

2017-01-10

individual subsystem scores ranged from 0.72 to 0.89. The CVME (N = 70) of the BESTest total score was 4.1%. The CVME for the subsystem scores ranged from 5.0% to 10.7%. MDC (N = 70) for the BESTest total score at the 95% CI was 7.6%, or 8.2 points. MDC at the 95% CI for subsystem scores ranged from 11.7% to 19.0% (2.1-3.4 points). Results demonstrated generally good to excellent interrater and test-retest reliability in both the BESTest total and subsystem scores with community-dwelling older adults. The BESTest total and individual subsystem scores demonstrate good to excellent interrater and test-retest reliability with community-dwelling older adults. A change of 7.6% (8.2 points) or more in the BESTest total and a percentage change ranged from 11.7% to 19.0% (2.1-3.4 points) in the subsystem scores are suggested for clinicians to be 95% confident of true change when evaluating change in this population.

Test-Retest Reliability of Computerized, Everyday Memory Measures and Traditional Memory Tests.

Science.gov (United States)

Youngjohn, James R.; And Others

Test-retest reliabilities and practice effect magnitudes were considered for nine computer-simulated tasks of everyday cognition and five traditional neuropsychological tests. The nine simulated everyday memory tests were from the Memory Assessment Clinic battery as follows: (1) simple reaction time while driving; (2) divided attention (driving…

13C-octanoic acid breath test for measurement of solid gastric emptying: reproducibility in normal subjects and patients with diabetes mellitus

International Nuclear Information System (INIS)

Feng Bo; Dan, Z.

2001-01-01

Objective: To examine the intra-individual reproducibility of the octanoic acid breath test in normal subjects and diabetics and to investigate whether cardiovascular autonomic neuropathy and delayed gastric emptying influence the intra-individual reproducibility. Methods: Nine normal subjects (six men, three women,mean age 38 years) and 15 diabetics with insulin treatment [nine men, six women; mean age 47 years; six had cardiovascular autonomic diabetic neuropathy (CADN) and/or delayed gastric emptying time] were, after a nocturnal fasting period, given a standard test meal (labelled with 13 C-octanoic acid, 1 046 kJ). Breath samples were taken at ten minute intervals over first one hour and at fifteen minute intervals over the following three hours and examined for 13 CO 2 by isotope ratio infrared spectrometry. Using a regression method gastric emptying half times (t 1/2 ) and lag phase (t lag ) were determined. Results: There was not a significant difference of t 1/2 and t lag between two measurements in normal subjects and diabetics. The coefficients of variation of day-to-day reproducibility were 11.7% for t 1/2 , 19.4% for t lag in normal subjects and 17.8% for t 1/2 , 28.2% for t lag in diabetics, but there was not significant difference between normal subjects and diabetics. There was not significant difference of intra-individual coefficient of variation of t 1/2 and t lag between diabetics with/without CADN and between diabetics with normal gastric emptying time and diabetics with delayed gastric emptying time. Conclusions: The 13 C-octanoic acid breath test has a high intra-individual reproducibility which is not affected by the cardiovascular autonomic neuropathy and delayed gastric emptying. It can be recommended as a non-invasive test for assessing gastric emptying time after a solid test meal in diabetics

Test-retest reliability of selected items of Health Behaviour in School-aged Children (HBSC survey questionnaire in Beijing, China

Directory of Open Access Journals (Sweden)

Liu Yang

2010-08-01

Full Text Available Abstract Background Children's health and health behaviour are essential for their development and it is important to obtain abundant and accurate information to understand young people's health and health behaviour. The Health Behaviour in School-aged Children (HBSC study is among the first large-scale international surveys on adolescent health through self-report questionnaires. So far, more than 40 countries in Europe and North America have been involved in the HBSC study. The purpose of this study is to assess the test-retest reliability of selected items in the Chinese version of the HBSC survey questionnaire in a sample of adolescents in Beijing, China. Methods A sample of 95 male and female students aged 11 or 15 years old participated in a test and retest with a three weeks interval. Student Identity numbers of respondents were utilized to permit matching of test-retest questionnaires. 23 items concerning physical activity, sedentary behaviour, sleep and substance use were evaluated by using the percentage of response shifts and the single measure Intraclass Correlation Coefficients (ICC with 95% confidence interval (CI for all respondents and stratified by gender and age. Items on substance use were only evaluated for school children aged 15 years old. Results The percentage of no response shift between test and retest varied from 32% for the item on computer use at weekends to 92% for the three items on smoking. Of all the 23 items evaluated, 6 items (26% showed a moderate reliability, 12 items (52% displayed a substantial reliability and 4 items (17% indicated almost perfect reliability. No gender and age group difference of the test-retest reliability was found except for a few items on sedentary behaviour. Conclusions The overall findings of this study suggest that most selected indicators in the HBSC survey questionnaire have satisfactory test-retest reliability for the students in Beijing. Further test-retest studies in a large

Test-retest reliability of a balance testing protocol with external perturbations in young healthy adults.

Science.gov (United States)

Robbins, Shawn M; Caplan, Ryan M; Aponte, Daniel I; St-Onge, Nancy

2017-10-01

External perturbations are utilized to challenge balance and mimic realistic balance threats in patient populations. The reliability of such protocols has not been established. The purpose was to examine test-retest reliability of balance testing with external perturbations. Healthy adults (n=34; mean age 23 years) underwent balance testing over two visits. Participants completed ten balance conditions in which the following parameters were combined: perturbation or non-perturbation, single or double leg, and eyes open or closed. Three trials were collected for each condition. Data were collected on a force plate and external perturbations were applied by translating the plate. Force plate center of pressure (CoP) data were summarized using 13 different CoP measures. Test-retest reliability was examined using intraclass correlation coefficients (ICC) and Bland-Altman plots. CoP measures of total speed and excursion in both anterior-posterior and medial-lateral directions generally had acceptable ICC values for perturbation conditions (ICC=0.46 to 0.87); however, many other CoP measures (e.g. range, area of ellipse) had unacceptable test-retest reliability (ICCbalance testing protocols that include external perturbations should be made to improve test-retest reliability and diminish learning including more extensive participant training and increasing the number of trials. CoP measures that consider all data points (e.g. total speed) are more reliable than those that only consider a few data points. Copyright © 2017 Elsevier B.V. All rights reserved.

Reproducibility of repeated measures of deuterium substituted [11C]L-deprenyl ([11C]L-deprenyl-D2) binding in the human brain

International Nuclear Information System (INIS)

Logan, Jean; Fowler, Joanna S.; Volkow, Nora D.; Wang, Gene-Jack; MacGregor, Robert R.; Shea, Colleen

2000-01-01

The purpose of this study was to assess the reproducibility of repeated positron emission tomography (PET) measures of brain monoamine oxidase B (MAO B) using deuterium-substituted [ 11 C]L-deprenyl ([ 11 C]L-deprenyl-D2) in normal subjects and to validate the method used for estimating the kinetic constants from the irreversible 3-compartment model applied to the tracer binding. Five normal healthy subjects (age range 23-73 years) each received two PET scans with [ 11 C]L-deprenyl-D2. The time interval between scans was 7-27 days. Time-activity data from eight regions of interest and an arterial plasma input function was used to calculate λk 3 , a model term proportional to MAO B, and K 1 , the plasma to brain transfer constant that is related to blood flow. Linear (LIN) and nonlinear least-squares (NLLSQ) estimation methods were used to calculate the optimum model constants. A comparison of time-activity curves for scan 1 and scan 2 showed that the percent of change for peak uptake varied from -18.5 to 15.0% and that increases and decreases in uptake on scan 2 were associated with increases and decreases in the value of the arterial input of the tracer. Calculation of λk 3 showed a difference between scan 1 and scan 2 in the global value ranging between -6.97 and 4.5% (average -2.1±4.7%). The average percent change for eight brain regions for the five subjects was -2.84±7.07%. Values of λk 3 for scan 1 and scan 2 were highly correlated (r 2 =0.98; p 1 showed a significant correlation between scan 1 and scan 2 (r 2 =0.61; p 11 C]L-deprenyl-D2 varied between scan 1 and scan 2, driven by the differences in arterial tracer input. Application of a 3-compartment model to regional time-activity data and arterial input function yielded λk 3 values for scan 1 and scan 2 with an average difference of -2.84 ± 7.07%. Linear regression applied to values of λk 3 from the LIN and NLLSQ methods validated the use of the linear method for calculating λk 3

Test-retest reliability of automated whole body and compartmental muscle volume measurements on a wide bore 3T MR system.

Science.gov (United States)

Thomas, Marianna S; Newman, David; Leinhard, Olof Dahlqvist; Kasmai, Bahman; Greenwood, Richard; Malcolm, Paul N; Karlsson, Anette; Rosander, Johannes; Borga, Magnus; Toms, Andoni P

2014-09-01

To measure the test-retest reproducibility of an automated system for quantifying whole body and compartmental muscle volumes using wide bore 3 T MRI. Thirty volunteers stratified by body mass index underwent whole body 3 T MRI, two-point Dixon sequences, on two separate occasions. Water-fat separation was performed, with automated segmentation of whole body, torso, upper and lower leg volumes, and manually segmented lower leg muscle volumes. Mean automated total body muscle volume was 19·32 L (SD9·1) and 19·28 L (SD9·12) for first and second acquisitions (Intraclass correlation coefficient (ICC) = 1·0, 95% level of agreement -0·32-0·2 L). ICC for all automated test-retest muscle volumes were almost perfect (0·99-1·0) with 95% levels of agreement 1.8-6.6% of mean volume. Automated muscle volume measurements correlate closely with manual quantification (right lower leg: manual 1·68 L (2SD0·6) compared to automated 1·64 L (2SD 0·6), left lower leg: manual 1·69 L (2SD 0·64) compared to automated 1·63 L (SD0·61), correlation coefficients for automated and manual segmentation were 0·94-0·96). Fully automated whole body and compartmental muscle volume quantification can be achieved rapidly on a 3 T wide bore system with very low margins of error, excellent test-retest reliability and excellent correlation to manual segmentation in the lower leg. Sarcopaenia is an important reversible complication of a number of diseases. Manual quantification of muscle volume is time-consuming and expensive. Muscles can be imaged using in and out of phase MRI. Automated atlas-based segmentation can identify muscle groups. Automated muscle volume segmentation is reproducible and can replace manual measurements.

Test-retest reliability of the Military Pre-training Questionnaire.

Science.gov (United States)

Robinson, M; Stokes, K; Bilzon, J; Standage, M; Brown, P; Thompson, D

2010-09-01

Musculoskeletal injuries are a significant cause of morbidity during military training. A brief, inexpensive and user-friendly tool that demonstrates reliability and validity is warranted to effectively monitor the relationship between multiple predictor variables and injury incidence in military populations. To examine the test-retest reliability of the Military Pre-training Questionnaire (MPQ), designed specifically to assess risk factors for injury among military trainees across five domains (physical activity, injury history, diet, alcohol and smoking). Analyses were based on a convenience sample of 58 male British Army trainees. Kappa (kappa), weighted kappa (kappa(w)) and intraclass correlation coefficients (ICC) were used to evaluate the 2-week test-retest reliability of the MPQ. For index measures constituting the assessment of a given construct, internal consistency was assessed by Cronbach's alpha (alpha) coefficients. Reliability of individual items ranged from poor to almost perfect (kappa range = 0.45-0.86; kappa(w) range = 0.11-0.91; ICC range = 0.34-0.86) with most items demonstrating moderate reliability. Overall scores related to physical activity, diet, alcohol and smoking constructs were reliable between both administrations (ICC = 0.63-0.85). Support for the internal consistency of the incorporated alcohol (alpha = 0.78) and cigarette (alpha = 0.75) scales was also provided. The MPQ is a reliable self-report instrument for assessing multiple injury-related risk factors during initial military training. Further assessment of the psychometric properties of the MPQ (e.g. different types of validity) with military populations/samples will support its interpretation and use in future surveillance and epidemiological studies.

Test-retest reliability of sensor-based sit-to-stand measures in young and older adults.

Science.gov (United States)

Regterschot, G Ruben H; Zhang, Wei; Baldus, Heribert; Stevens, Martin; Zijlstra, Wiebren

2014-01-01

This study investigated test-retest reliability of sensor-based sit-to-stand (STS) peak power and other STS measures in young and older adults. In addition, test-retest reliability of the sensor method was compared to test-retest reliability of the Timed Up and Go Test (TUGT) and Five-Times-Sit-to-Stand Test (FTSST) in older adults. Ten healthy young female adults (20-23 years) and 31 older adults (21 females; 73-94 years) participated in two assessment sessions separated by 3-8 days. Vertical peak power was assessed during three (young adults) and five (older adults) normal and fast STS trials with a hybrid motion sensor worn on the hip. Older adults also performed the FTSST and TUGT. The average sensor-based STS peak power of the normal STS trials and the average sensor-based STS peak power of the fast STS trials showed excellent test-retest reliability in young adults (intra-class correlation (ICC)≥0.90; zero in 95% confidence interval of mean difference between test and retest (95%CI of D); standard error of measurement (SEM)≤6.7% of mean peak power) and older adults (ICC≥0.91; zero in 95%CI of D; SEM≤9.9%). Test-retest reliability of sensor-based STS peak power and TUGT (ICC=0.98; zero in 95%CI of D; SEM=8.5%) was comparable in older adults, test-retest reliability of the FTSST was lower (ICC=0.73; zero outside 95%CI of D; SEM=14.4%). Sensor-based STS peak power demonstrated excellent test-retest reliability and may therefore be useful for clinical assessment of functional status and fall risk. Copyright © 2014 Elsevier B.V. All rights reserved.

Test of cure, retesting and extragenital testing practices for Chlamydia trachomatis and Neisseria gonorrhoeae among general practitioners in different socioeconomic status areas: A retrospective cohort study, 2011-2016

Science.gov (United States)

van Liere, Geneviève A. F. S.; Cals, Jochen W. L.; Dukers-Muijrers, Nicole H. T. M.

2018-01-01

Background For Chlamydia trachomatis (CT), a test of cure (TOC) within 3–5 weeks is not recommended. International guidelines differ in advising a Neisseria gonorrhoeae (NG) TOC. Retesting CT and NG positives within 3–12 months is recommended in international guidelines. We assessed TOC and retesting practices including extragenital testing in general practitioner (GP) practices located in different socioeconomic status (SES) areas to inform and optimize local test practices. Methods Laboratory data of 48 Dutch GP practices between January 2011 and July 2016 were used. Based on a patient’s first positive CT or NG test, the proportion of TOC (TOC and 24% had a retest at the GP practice. GP practices in low SES areas were more likely to perform a CT TOC (OR:1.8;95%CI:1.1–3.1). Younger patients (TOC (OR:1.6;95%CI:1.0–2.4). For CT (n = 622), 2.4% had a TOC and 6.1% had a retest at another STI care provider. For NG (n = 73), 25% had a TOC and 15% had a retest at the GP practice. For NG (n = 73), 2.7% had a TOC and 12.3% had a retest at another STI care provider. In only 0.3% of the consultations patients were tested on extragenital sites. Conclusion Almost 20% of the patients returned for a CT TOC, especially at GP practices in low SES areas. For NG, 1 out of 4 patients returned for a TOC. Retesting rates were low for both CT (24%) and NG (15%), (re)infections including extragenital infections may be missed. Efforts are required to focus TOC and increase retesting practices of GPs in order to improve CT/NG control. PMID:29538469

The Comprehensive Snack Parenting Questionnaire (CSPQ: Development and Test-Retest Reliability

Directory of Open Access Journals (Sweden)

Dorus W. M. Gevers

2018-04-01

Full Text Available The narrow focus of existing food parenting instruments led us to develop a food parenting practices instrument measuring the full range of food practices constructs with a focus on snacking behavior. We present the development of the questionnaire and our research on the test-retest reliability. The developed Comprehensive Snack Parenting Questionnaire (CSPQ covers 21 constructs. Test-retest reliability was assessed by calculating intra class correlation coefficients and percentage agreement after two administrations of the CSPQ among a sample of 66 Dutch parents. Test-retest reliability analysis revealed acceptable intra class correlation coefficients (≥0.41 or agreement scores (≥0.60 for all items. These results, together with earlier work, suggest sufficient psychometric characteristics. The comprehensive, but brief CSPQ opens up chances for highly essential but unstudied research questions to understand and predict children’s snack intake. Example applications include studying the interactional nature of food parenting practices or interactions of food parenting with general parenting or child characteristics.

Characterisation of [11C]PR04.MZ in Papio anubis baboon: A selective high-affinity radioligand for quantitative imaging of the dopamine transporter

Energy Technology Data Exchange (ETDEWEB)

Riss P. J.; Fowler J.; Riss, P.J.; Hooker, J.M.; Shea, C.; Xu, Y.; Carter, P.; Warner, D.; Ferrari V.; Kim, S.W.; Aigbirhio, F.I.; Fowler, J.S.; Roesch, F.

2011-10-25

N-(4-fluorobut-2-yn-1-yl)-2{beta}-carbomethoxy-3{beta}-(4{prime}-tolyl)nortropane (PR04.MZ, 1) is a PET radioligand for the non-invasive exploration of the function of the cerebral dopamine transporter (DAT). A reliable automated process for routine production of the carbon-11 labelled analogue [{sup 11}C]PR04.MZ ([{sup 11}C]-1) has been developed using GMP compliant equipment. An adult female Papioanubis baboon was studied using a test-retest protocol with [{sup 11}C]-1 in order to assess test-retest reliability, metabolism and CNS distribution profile of the tracer in non-human primates. Blood sampling was performed throughout the studies for determination of the free fraction in plasma (fP), plasma input functions and metabolic degradation of the radiotracer [{sup 11}C]-1. Time-activity curves were derived for the putamen, the caudate nucleus, the ventral striatum, the midbrain and the cerebellum. Distribution volumes (VT) and non-displaceable binding potentials (BPND) for various brain regions and the blood were obtained from kinetic modelling. [{sup 11}C]-1 shows promising results as aselective marker of the presynaptic dopamine transporter. With the reliable visualisation of the extra-striatal dopaminergic neurons and no indication on labelled metabolites, the tracer provides excellent potential for translation into man.

Re-test reliability of gustatory testing and introduction of the sensitive Taste-Drop-Test

DEFF Research Database (Denmark)

Fjaeldstad, A; Niklassen, A; Fernandes, H

2018-01-01

. Testing gustatory function can be important for diagnostics and assessment of treatment effects. However, the gustatory tests applied are required to be both sensitive and reliable.In this study, we investigate the re-test validity of popular Taste Strips gustatory test for gustatory screening....... Furthermore, we introduce a new sensitive Taste-Drop-Test, which was found to be superior for detecting a more accurate measure of tastant sensitivity....

Retesting with the TRUE Test in a population-based twin cohort with hand eczema

DEFF Research Database (Denmark)

Lerbaek, Anne; Kyvik, Kirsten Ohm; Menné, Torkil

2007-01-01

Population-based studies on contact allergy with retesting of individuals are infrequently performed. Variable degrees of persistence are reported when individuals with contact allergy are retested with years in between. The patch test results of 270 individuals tested in 2005-2006 are presented ...

Automated radiochemical synthesis and biodistribution of [11C]l-α-acetylmethadol ([11C]LAAM)

International Nuclear Information System (INIS)

Sai, Kiran Kumar Solingapuram; Fan, Jinda; Tu, Zhude; Zerkel, Patrick; Mach, Robert H.; Kharasch, Evan D.

2014-01-01

Long-acting opioid agonists methadone and l-α-acetylmethadol (LAAM) prevent withdrawal in opioid-dependent persons. Attempts to synthesize [ 11 C]-methadone for PET evaluation of brain disposition were unsuccessful. Owing, however, to structural and pharmacologic similarities, we aimed to develop [ 11 C]LAAM as a PET ligand to probe the brain exposure of long-lasting opioids in humans. This manuscript describes [ 11 C]LAAM synthesis and its biodistribution in mice. The radiochemical synthetic strategy afforded high radiochemical yield, purity and specific activity, thereby making the synthesis adaptable to automated modules. - Highlights: • Radiochemical synthesis of opioid [ 11 C]l-α-acetylmethadol (LAAM) described for the first time. • High radiochemical yield, purity and specific activity. • Easily reproducible and adaptable synthesis to any C-11 automated modules. • [ 11 C]LAAM utility as a PET radiopharmaceutical for assessing brain penetration

Reproducibility of a 3-dimensional gyroscope in measuring shoulder anteflexion and abduction

Directory of Open Access Journals (Sweden)

Penning Ludo I F

2012-07-01

Full Text Available Abstract Background Few studies have investigated the use of a 3-dimensional gyroscope for measuring the range of motion (ROM in the impaired shoulder. Reproducibility of digital inclinometer and visual estimation is poor. This study aims to investigate the reproducibility of a tri axial gyroscope in measurement of anteflexion, abduction and related rotations in the impaired shoulder. Methods Fifty-eight patients with either subacromial impingement (27 or osteoarthritis of the shoulder (31 participated. Active anteflexion, abduction and related rotations were measured with a tri axial gyroscope according to a test retest protocol. Severity of shoulder impairment and patient perceived pain were assessed by the Disability of Arm Shoulder and Hand score (DASH and the Visual Analogue Scale (VAS. VAS scores were recorded before and after testing. Results In two out of three hospitals patients with osteoarthritis (n = 31 were measured, in the third hospital patients with subacromial impingement (n = 27. There were significant differences among hospitals for the VAS and DASH scores measured before and after testing. The mean differences between the test and retest means for anteflexion were −6 degrees (affected side, 9 (contralateral side and for abduction 15 degrees (affected side and 10 degrees (contralateral side. Bland & Altman plots showed that the confidence intervals for the mean differences fall within −6 up to 15 degrees, individual test - retest differences could exceed these limits. A simulation according to ‘Generalizability Theory’ produces very good coefficients for anteflexion and related rotation as a comprehensive measure of reproducibility. Optimal reproducibility is achieved with 2 repetitions for anteflexion. Conclusions Measurements were influenced by patient perceived pain. Differences in VAS and DASH might be explained by different underlying pathology. These differences in shoulder pathology however did not alter

Test-retest reliability of the Danish Adult Reading Test in patients with comorbid psychosis and cannabis-use disorder

DEFF Research Database (Denmark)

Hjorthøj, Carsten Rygaard; Vesterager, Lone; Nordentoft, Merete

2013-01-01

Background: The New Adult Reading Test is a common instrument for assessing pre-morbid IQ for patients with, for instance, schizophrenia. However, test-retest reliability has not been established for patients dually diagnosed with psychosis and substance use disorder. Furthermore, test......-retest reliability of the Danish adaptation has never been established in any population. Aims: To determine the test-retest reliability of the Danish Adult Reading Test (DART) (adapted from the National Adult Reading Test, NART) for patients dually diagnosed with psychosis and cannabis-use disorder. Methods......: This was a secondary analysis of the CapOpus randomized trial. As part of the trial, 103 patients were randomized, and completed the DART up to three times. Pearson's r and pairwise t-tests were calculated. Results: DART score was independent of randomization, cannabis-use frequency and psychopathology. Scores...

Sub-maximal and maximal Yo-Yo intermittent endurance test level 2: heart rate response, reproducibility and application to elite soccer

DEFF Research Database (Denmark)

Bradley, Paul S; Mohr, Magni; Bendiksen, Mads

2011-01-01

to detect test-retest changes and discriminate between performance for different playing standards and positions in elite soccer. Elite (n = 148) and sub-elite male (n = 14) soccer players carried out the Yo-Yo IE2 test on several occasions over consecutive seasons. Test-retest coefficient of variation (CV......) in Yo-Yo IE2 test performance and heart rate after 6 min were 3.9% (n = 37) and 1.4% (n = 32), respectively. Elite male senior and youth U19 players Yo-Yo IE2 performances were better (P ......The aims of this study were to (1) determine the reproducibility of sub-maximal and maximal versions of the Yo-Yo intermittent endurance test level 2 (Yo-Yo IE2 test), (2) assess the relationship between the Yo-Yo IE2 test and match performance and (3) quantify the sensitivity of the Yo-Yo IE2 test...

Test-Retest Reliability of a Survey to Measure Transport-Related Physical Activity in Adults

Science.gov (United States)

Badland, Hannah; Schofield, Grant

2006-01-01

The present research details test-retest reliability of a newly developed, telephone-administered TPA survey for adults. This instrument examines barriers, perceptions, and current travel behaviors to place of work/study and local convenience shops. Demonstrated test-retest reliability of the Active Friendly Environments-Transport-Related Physical…

Test-Retest Reliability of Measures Commonly Used to Measure Striatal Dysfunction across Multiple Testing Sessions: A Longitudinal Study.

Science.gov (United States)

Palmer, Clare E; Langbehn, Douglas; Tabrizi, Sarah J; Papoutsi, Marina

2017-01-01

Cognitive impairment is common amongst many neurodegenerative movement disorders such as Huntington's disease (HD) and Parkinson's disease (PD) across multiple domains. There are many tasks available to assess different aspects of this dysfunction, however, it is imperative that these show high test-retest reliability if they are to be used to track disease progression or response to treatment in patient populations. Moreover, in order to ensure effects of practice across testing sessions are not misconstrued as clinical improvement in clinical trials, tasks which are particularly vulnerable to practice effects need to be highlighted. In this study we evaluated test-retest reliability in mean performance across three testing sessions of four tasks that are commonly used to measure cognitive dysfunction associated with striatal impairment: a combined Simon Stop-Signal Task; a modified emotion recognition task; a circle tracing task; and the trail making task. Practice effects were seen between sessions 1 and 2 across all tasks for the majority of dependent variables, particularly reaction time variables; some, but not all, diminished in the third session. Good test-retest reliability across all sessions was seen for the emotion recognition, circle tracing, and trail making test. The Simon interference effect and stop-signal reaction time (SSRT) from the combined-Simon-Stop-Signal task showed moderate test-retest reliability, however, the combined SSRT interference effect showed poor test-retest reliability. Our results emphasize the need to use control groups when tracking clinical progression or use pre-baseline training on tasks susceptible to practice effects.

Test-retest studies of cerebral glucose metabolism using fluorine-18 deoxyglucose: validation of method

International Nuclear Information System (INIS)

Brooks, R.A.; Di Chiro, G.; Zukerberg, B.W.; Bairamian, D.; Larson, S.M.

1987-01-01

In studies using [ 18 F]deoxyglucose (FDG), one often wants to compare metabolic rates following stimulation (drug or motor-sensory) with the baseline values. However, because of reproducibility problems with baseline variations of 25% in the same individual not uncommon, the global effect of the stimulation may be difficult to see. One approach to this problem is to perform the two studies sequentially. This means that, with the 110-min half-life of 18 F, one must take into account the residual activity from the first study when calculating metabolic rates for the second. We performed TEST-RETEST baseline studies on four subjects, with a 1-hr interval between injections. These studies were done without stimulation, in order to validate the repeatability of the method. To reduce the amount of residual activity from the first study, the first injection was only 2 mCi in three cases, and only 1 mCi in one case, out of a total injected dose of 5 mCi. A correction for residual activity was included in the RETEST calculation of metabolic rate. The results showed a global metabolic shift between the two studies of 2% to 9%. An error analysis shows that the shift could be further reduced if anatomically comparable scans are done at comparable postinjection times

Interna konzistencija i retest pouzdanost hrvatske inačice PAQ-C upitnika

OpenAIRE

Podnar, Hrvoje; Kunješić, Mateja; Radman, Ivan

2017-01-01

The aim of the study was to determine internal consistency and retest reliability of the Croatian version of PAQ-C on a sample of 6-10 years old children and to report physical activity levels of elementary school pupils. The same set of questions was administered to the pupils on two different occasions, three weeks apart. Both testing rounds for 8-10 years old pupils were conducted at school in the presence of an experienced researcher. In contrast, the 6-8 years old pupils took the questio...

Reproducibility of Automated Voice Range Profiles, a Systematic Literature Review

DEFF Research Database (Denmark)

Printz, Trine; Rosenberg, Tine; Godballe, Christian

2018-01-01

literature on test-retest accuracy of the automated voice range profile assessment. Study design: Systematic review. Data sources: PubMed, Scopus, Cochrane Library, ComDisDome, Embase, and CINAHL (EBSCO). Methods: We conducted a systematic literature search of six databases from 1983 to 2016. The following......Objective: Reliable voice range profiles are of great importance when measuring effects and side effects from surgery affecting voice capacity. Automated recording systems are increasingly used, but the reproducibility of results is uncertain. Our objective was to identify and review the existing...... keywords were used: phonetogram, voice range profile, and acoustic voice analysis. Inclusion criteria were automated recording procedure, healthy voices, and no intervention between test and retest. Test-retest values concerning fundamental frequency and voice intensity were reviewed. Results: Of 483...

A PET imaging agent with fast kinetics: synthesis and in vivo evaluation of the serotonin transporter ligand [{sup 11}C]2-[2-dimethylaminomethylphenylthio]-5-fluorophenylamine ([{sup 11}C]AFA)

Energy Technology Data Exchange (ETDEWEB)

Huang Yiyun E-mail: hh285@columbia.edu; Narendran, Raj; Bae, Sung-A; Erritzoe, David; Guo Ningning; Zhu Zhihong; Hwang, D.-R.; Laruelle, Marc

2004-08-01

;') of [{sup 11}C]AFA are similar to those of [{sup 11}C]McN5652, but lower than those of [{sup 11}C]AFM or [{sup 11}C]DASB. In summary, [{sup 11}C]AFA appears to be an appropriate PET radioligand with a fast brain uptake kinetics:.

Test-Retest Reliability and Predictive Validity of the Implicit Association Test in Children

Science.gov (United States)

Rae, James R.; Olson, Kristina R.

2018-01-01

The Implicit Association Test (IAT) is increasingly used in developmental research despite minimal evidence of whether children's IAT scores are reliable across time or predictive of behavior. When test-retest reliability and predictive validity have been assessed, the results have been mixed, and because these studies have differed on many…

Test-retest reliability of trunk accelerometric gait analysis

DEFF Research Database (Denmark)

Henriksen, Marius; Lund, Hans; Moe-Nilssen, R

2004-01-01

The purpose of this study was to determine the test-retest reliability of a trunk accelerometric gait analysis in healthy subjects. Accelerations were measured during walking using a triaxial accelerometer mounted on the lumbar spine of the subjects. Six men and 14 women (mean age 35.2; range 18...... a definite potential in clinical gait analysis....

Test-retest reliability of automated whole body and compartmental muscle volume measurements on a wide bore 3T MR system

Energy Technology Data Exchange (ETDEWEB)

Thomas, Marianna S.; Newman, David; Kasmai, Bahman; Greenwood, Richard; Malcolm, Paul N. [Norfolk and Norwich University Hospital, Department of Radiology, Norwich (United Kingdom); Leinhard, Olof Dahlqvist [Linkoeping University, Center for Medical Image Science and Visualization, Linkoeping (Sweden); Linkoeping University, Department of Medical and Health Sciences, Linkoeping (Sweden); Karlsson, Anette; Borga, Magnus [Linkoeping University, Center for Medical Image Science and Visualization, Linkoeping (Sweden); Linkoeping University, Department of Biomedical Engineering, Linkoeping (Sweden); Rosander, Johannes [Advanced MR Analytics AB, Linkoeping (Sweden); Toms, Andoni P. [Norfolk and Norwich University Hospital, Department of Radiology, Norwich (United Kingdom); Radiology Academy, Cotman Centre, Norwich, Norfolk (United Kingdom)

2014-09-15

To measure the test-retest reproducibility of an automated system for quantifying whole body and compartmental muscle volumes using wide bore 3 T MRI. Thirty volunteers stratified by body mass index underwent whole body 3 T MRI, two-point Dixon sequences, on two separate occasions. Water-fat separation was performed, with automated segmentation of whole body, torso, upper and lower leg volumes, and manually segmented lower leg muscle volumes. Mean automated total body muscle volume was 19.32 L (SD9.1) and 19.28 L (SD9.12) for first and second acquisitions (Intraclass correlation coefficient (ICC) = 1.0, 95 % level of agreement -0.32-0.2 L). ICC for all automated test-retest muscle volumes were almost perfect (0.99-1.0) with 95 % levels of agreement 1.8-6.6 % of mean volume. Automated muscle volume measurements correlate closely with manual quantification (right lower leg: manual 1.68 L (2SD0.6) compared to automated 1.64 L (2SD 0.6), left lower leg: manual 1.69 L (2SD 0.64) compared to automated 1.63 L (SD0.61), correlation coefficients for automated and manual segmentation were 0.94-0.96). Fully automated whole body and compartmental muscle volume quantification can be achieved rapidly on a 3 T wide bore system with very low margins of error, excellent test-retest reliability and excellent correlation to manual segmentation in the lower leg. (orig.)

Test-retest reliability of automated whole body and compartmental muscle volume measurements on a wide bore 3T MR system

International Nuclear Information System (INIS)

Thomas, Marianna S.; Newman, David; Kasmai, Bahman; Greenwood, Richard; Malcolm, Paul N.; Leinhard, Olof Dahlqvist; Karlsson, Anette; Borga, Magnus; Rosander, Johannes; Toms, Andoni P.

2014-01-01

To measure the test-retest reproducibility of an automated system for quantifying whole body and compartmental muscle volumes using wide bore 3 T MRI. Thirty volunteers stratified by body mass index underwent whole body 3 T MRI, two-point Dixon sequences, on two separate occasions. Water-fat separation was performed, with automated segmentation of whole body, torso, upper and lower leg volumes, and manually segmented lower leg muscle volumes. Mean automated total body muscle volume was 19.32 L (SD9.1) and 19.28 L (SD9.12) for first and second acquisitions (Intraclass correlation coefficient (ICC) = 1.0, 95 % level of agreement -0.32-0.2 L). ICC for all automated test-retest muscle volumes were almost perfect (0.99-1.0) with 95 % levels of agreement 1.8-6.6 % of mean volume. Automated muscle volume measurements correlate closely with manual quantification (right lower leg: manual 1.68 L (2SD0.6) compared to automated 1.64 L (2SD 0.6), left lower leg: manual 1.69 L (2SD 0.64) compared to automated 1.63 L (SD0.61), correlation coefficients for automated and manual segmentation were 0.94-0.96). Fully automated whole body and compartmental muscle volume quantification can be achieved rapidly on a 3 T wide bore system with very low margins of error, excellent test-retest reliability and excellent correlation to manual segmentation in the lower leg. (orig.)

Test-Retest Reliability of the Salutogenic Wellness Promotion Scale (SWPS)

Science.gov (United States)

Anderson, L. M.; Moore, J. B.; Hayden, B. M.; Becker, C. M.

2014-01-01

Objective: This study examined the temporal stability (i.e. test-retest reliability) of the Salutogenic Wellness Promotion Scale (SWPS) using intraclass correlation coefficients (ICC). Current intraclass results were also compared to previously published interclass correlations to support the use of the intraclass method for test-retest…

Test-retest reliability of jump execution variables using mechanography: a comparison of jump protocols.

Science.gov (United States)

Fitzgerald, John S; Johnson, LuAnn; Tomkinson, Grant; Stein, Jesse; Roemmich, James N

2018-05-01

Mechanography during the vertical jump may enhance screening and determining mechanistic causes underlying physical performance changes. Utility of jump mechanography for evaluation is limited by scant test-retest reliability data on force-time variables. This study examined the test-retest reliability of eight jump execution variables assessed from mechanography. Thirty-two women (mean±SD: age 20.8 ± 1.3 yr) and 16 men (age 22.1 ± 1.9 yr) attended a familiarization session and two testing sessions, all one week apart. Participants performed two variations of the squat jump with squat depth self-selected and controlled using a goniometer to 80º knee flexion. Test-retest reliability was quantified as the systematic error (using effect size between jumps), random error (using coefficients of variation), and test-retest correlations (using intra-class correlation coefficients). Overall, jump execution variables demonstrated acceptable reliability, evidenced by small systematic errors (mean±95%CI: 0.2 ± 0.07), moderate random errors (mean±95%CI: 17.8 ± 3.7%), and very strong test-retest correlations (range: 0.73-0.97). Differences in random errors between controlled and self-selected protocols were negligible (mean±95%CI: 1.3 ± 2.3%). Jump execution variables demonstrated acceptable reliability, with no meaningful differences between the controlled and self-selected jump protocols. To simplify testing, a self-selected jump protocol can be used to assess force-time variables with negligible impact on measurement error.

Test-retest and interrater reliability of the functional lower extremity evaluation.

Science.gov (United States)

Haitz, Karyn; Shultz, Rebecca; Hodgins, Melissa; Matheson, Gordon O

2014-12-01

Repeated-measures clinical measurement reliability study. To establish the reliability and face validity of the Functional Lower Extremity Evaluation (FLEE). The FLEE is a 45-minute battery of 8 standardized functional performance tests that measures 3 components of lower extremity function: control, power, and endurance. The reliability and normative values for the FLEE in healthy athletes are unknown. A face validity survey for the FLEE was sent to sports medicine personnel to evaluate the level of importance and frequency of clinical usage of each test included in the FLEE. The FLEE was then administered and rated for 40 uninjured athletes. To assess test-retest reliability, each athlete was tested twice, 1 week apart, by the same rater. To assess interrater reliability, 3 raters scored each athlete during 1 of the testing sessions. Intraclass correlation coefficients were used to assess the test-retest and interrater reliability of each of the FLEE tests. In the face validity survey, the FLEE tests were rated as highly important by 58% to 71% of respondents but frequently used by only 26% to 45% of respondents. Interrater reliability intraclass correlation coefficients ranged from 0.83 to 1.00, and test-retest reliability ranged from 0.71 to 0.95. The FLEE tests are considered clinically important for assessing lower extremity function by sports medicine personnel but are underused. The FLEE also is a reliable assessment tool. Future studies are required to determine if use of the FLEE to make return-to-play decisions may reduce reinjury rates.

Fiabilidad del test 6 minutos caminando en personas con secuelas de poliomielitis paralítica mediante test-retest de 12 semanas

Directory of Open Access Journals (Sweden)

Francisco Javier Domínguez-Muñoz

2013-01-01

Full Text Available El análisis de la fiabilidad del test de 6 minutos ca- minando en una población de personas con secuelas de poliomielitis paralítica mediante test-retest de 12 semanas no ha sido estudiado. Participaron personas con secuelas de poliomielitis paralítica (n = 18; 48,72 ± 7,69 años; 65,8 ± 11,6 kg. Se les realizó un test-retest de 12 semanas de la prueba de 6 minutos caminando que consistía en que los sujetos anduvieran la mayor distan- cia, sin llegar a la carrera, en un periodo de 6 minutos. La fiabilidad relativa de la prueba fue excelente (CCI = 0,99. En lo que se refiere a la fiabilidad absoluta se obtuvo un error estándar de medida (SEM del 1,7% y un mínimo cambio real (SRD de 4,7%. La fiabilidad del test de 6 minutos caminando usando el método Bland- Altman mostró que el error sistemático (diferencia de medias entre el test-retest fue 2,72 (bias. En conclu- sión, los resultados obtenidos en el test de 6 minutos ca- minando han sido muy fiables y afirmamos que la prue- ba de 6 minutos caminando podrá ser utilizada como prueba de evaluación en una población con secuelas de poliomielitis paralítica, con un intervalo de 12 semanas entre las dos mediciones, para comprobar los cambios que se han producido tras la aplicación de un programa de actividad física.

Intrasubject reproducibility of presurgical language lateralization and mapping using fMRI.

NARCIS (Netherlands)

Fernandez, G.S.E.; Specht, K.; Weis, S.; Tendolkar, I.; Reuber, M.; Fell, J.; Klaver, P.; Ruhlmann, J.; Reul, J.; Elger, C.E.

2003-01-01

BACKGROUND: fMRI is becoming a standard tool for the presurgical lateralization and mapping of brain areas involved in language processing. However, its within-subject reproducibility has yet to be fully explored. OBJECTIVE: To evaluate within-test and test-retest reliability of language fMRI in

Test-retest reliability at the item level and total score level of the Norwegian version of the Spinal Cord Injury Falls Concern Scale (SCI-FCS).

Science.gov (United States)

Roaldsen, Kirsti Skavberg; Måøy, Åsa Blad; Jørgensen, Vivien; Stanghelle, Johan Kvalvik

2016-05-01

Translation of the Spinal Cord Injury Falls Concern Scale (SCI-FCS), and investigation of test-retest reliability on item-level and total-score-level. Translation, adaptation and test-retest study. A specialized rehabilitation setting in Norway. Fifty-four wheelchair users with a spinal cord injury. The median age of the cohort was 49 years, and the median number of years after injury was 13. Interventions/measurements: The SCI-FCS was translated and back-translated according to guidelines. Individuals answered the SCI-FCS twice over the course of one week. We investigated item-level test-retest reliability using Svensson's rank-based statistical method for disagreement analysis of paired ordinal data. For relative reliability, we analyzed the total-score-level test-retest reliability with intraclass correlation coefficients (ICC2.1), the standard error of measurement (SEM), and the smallest detectable change (SDC) for absolute reliability/measurement-error assessment and Cronbach's alpha for internal consistency. All items showed satisfactory percentage agreement (≥69%) between test and retest. There were small but non-negligible systematic disagreements among three items; we recovered an 11-13% higher chance for a lower second score. There was no disagreement due to random variance. The test-retest agreement (ICC2.1) was excellent (0.83). The SEM was 2.6 (12%), and the SDC was 7.1 (32%). The Cronbach's alpha was high (0.88). The Norwegian SCI-FCS is highly reliable for wheelchair users with chronic spinal cord injuries.

Test-retest reliability and validity of the Sniffin' TOM odor memory test.

Science.gov (United States)

Croy, Ilona; Zehner, Cora; Larsson, Maria; Zucco, Gesualdo M; Hummel, Thomas

2015-03-01

Few attempts have been made to develop an olfactory test that captures episodic retention of olfactory information. Assessment of episodic odor memory is of particular interest in aging and in the cognitively impaired as both episodic memory deficits and olfactory loss have been targeted as reliable hallmarks of cognitive decline and impending dementia. Here, 96 healthy participants (18-92 years) and an additional 19 older people with mild cognitive impairment were tested (73-82 years). Participants were presented with 8 common odors with intentional encoding instructions that were followed by a yes-no recognition test. After recognition completion, participants were asked to identify all odors by means of free or cued identification. A retest of the odor memory test (Sniffin' TOM = test of odor memory) took place 17 days later. The results revealed satisfactory test-retest reliability (0.70) of odor recognition memory. Both recognition and identification performance were negatively affected by age and more pronounced among the cognitively impaired. In conclusion, the present work presents a reliable, valid, and simple test of episodic odor recognition memory that may be used in clinical groups where both episodic memory deficits and olfactory loss are prevalent preclinically such as Alzheimer's disease. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Construct Validity and Test-Retest Reliability of the Climbing Stairs Questionnaire in Lower-Limb Amputees

NARCIS (Netherlands)

de Laat, Fred A.; Rommers, Gerardus M.; Geertzen, Jan H.; Roorda, Leo D.

de Laat FA, Rommers GM, Geertzen JH, Roorda LD. Construct validity and test-retest reliability of the Climbing Stairs Questionnaire in lower-limb amputees. Arch Phys Med Rehabil 2010;91:1396-401. Objective: To investigate the construct validity and test-retest reliability of the Climbing Stairs

Test-Retest Reliability and Minimal Detectable Change of the D2 Test of Attention in Patients with Schizophrenia.

Science.gov (United States)

Lee, Posen; Lu, Wen-Shian; Liu, Chin-Hsuan; Lin, Hung-Yu; Hsieh, Ching-Lin

2017-12-08

The d2 Test of Attention (D2) is a commonly used measure of selective attention for patients with schizophrenia. However, its test-retest reliability and minimal detectable change (MDC) are unknown in patients with schizophrenia, limiting its utility in both clinical and research settings. The aim of the present study was to examine the test-retest reliability and MDC of the D2 in patients with schizophrenia. A rater administered the D2 on 108 patients with schizophrenia twice at a 1-month interval. Test-retest reliability was determined through the calculation of the intra-class correlation coefficient (ICC). We also carried out Bland-Altman analysis, which included a scatter plot of the differences between test and retest against their mean. Systematic biases were evaluated by use of a paired t-test. The ICCs for the D2 ranged from 0.78 to 0.94. The MDCs (MDC%) of the seven subscores were 102.3 (29.7), 19.4 (85.0), 7.2 (94.6), 21.0 (69.0), 104.0 (33.1), 105.0 (35.8), and 7.8 (47.8), which represented limited-to-acceptable random measurement error. Trends in the Bland-Altman plots of the omissions (E1), commissions (E2), and errors (E) were noted, presenting that the data had heteroscedasticity. According to the results, the D2 had good test-retest reliability, especially in the scores of TN, TN-E, and CP. For the further research, finding a way to improve the administration procedure to reduce random measurement error would be important for the E1, E2, E, and FR subscores. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Test-retest reliability for aerodynamic measures of voice.

Science.gov (United States)

Awan, Shaheen N; Novaleski, Carolyn K; Yingling, Julie R

2013-11-01

The purpose of this study was to investigate the intrasubject reliability of aerodynamic characteristics of the voice within typical/normal speakers across testing sessions using the Phonatory Aerodynamic System (PAS 6600; KayPENTAX, Montvale, NJ). Participants were 60 healthy young adults (30 males and 30 females) between the ages 18 and 31 years with perceptually typical voice. Participants were tested using the PAS 6600 (Phonatory Aerodynamic System) on two separate days with approximately 1 week between each session at approximately the same time of day. Four PAS protocols were conducted (vital capacity, maximum sustained phonation, comfortable sustained phonation, and voicing efficiency) and measures of expiratory volume, maximum phonation time, mean expiratory airflow (during vowel production) and target airflow (obtained via syllable repetition), peak air pressure, aerodynamic power, aerodynamic resistance, and aerodynamic efficiency were obtained during each testing session. Associated acoustic measures of vocal intensity and frequency were also collected. All phonations were elicited at comfortable pitch and loudness. All aerodynamic and associated variables evaluated in this study showed useable test-retest reliability (ie, intraclass correlation coefficients [ICCs] ≥ 0.60). A high degree of mean test-retest reliability was found across all subjects for aerodynamic and associated acoustic measurements of vital capacity, maximum sustained phonation, glottal resistance, and vocal intensity (all with ICCs > 0.75). Although strong ICCs were observed for measures of glottal power and mean expiratory airflow in males, weaker overall results for these measures (ICC range: 0.60-0.67) were observed in females subjects and sizable coefficients of variation were observed for measures of power, resistance, and efficiency in both men and women. Differences in degree of reliability from measure to measure were revealed in greater detail using methods such as ICCs and

The Dichotic Digits difference Test (DDdT): Development, Normative Data, and Test-Retest Reliability Studies Part 1.

Science.gov (United States)

Cameron, Sharon; Glyde, Helen; Dillon, Harvey; Whitfield, Jessica; Seymour, John

2016-06-01

The dichotic digits test is one of the most widely used assessment tools for central auditory processing disorder. However, questions remain concerning the impact of cognitive factors on test results. To develop the Dichotic Digits difference Test (DDdT), an assessment tool that could differentiate children with cognitive deficits from children with genuine dichotic deficits based on differential test results. The DDdT consists of four subtests: dichotic free recall (FR), dichotic directed left ear (DLE), dichotic directed right ear (DRE), and diotic. Scores for six conditions are calculated (FR left ear [LE], FR right ear [RE], and FR total, as well as DLE, DRE, and diotic). Scores for four difference measures are also calculated: dichotic advantage, right-ear advantage (REA) FR, REA directed, and attention advantage. Experiment 1 involved development of the DDdT, including error rate analysis. Experiment 2 involved collection of normative and test-retest reliability data. Twenty adults (aged 25 yr 10 mo to 50 yr 7 mo, mean 36 yr 4 mo) took part in the development study; 62 normal-hearing, typically developing, primary-school children (aged 7 yr 1 mo to 11 yr 11 mo, mean 9 yr 4 mo) and 10 adults (aged 25 yr 0 mo to 51 yr 6 mo, mean 34 yr 10 mo) took part in the normative and test-retest reliability study. In Experiment 1, error rate analysis was conducted on the 36 digit-pair combinations of the DDdT. Normative data collected in Experiment 2 were arcsine transformed to achieve a distribution that was closer to a normal distribution and z-scores calculated. Pearson product-moment correlations were used to determine the strength of relationships between DDdT conditions. The development study revealed no significant differences in the adult population between test and retest on any DDdT condition. Error rates on 36 digit pairs ranged from 1.5% to 16.7%. The most and the least error-prone digits were removed before commencement of the normative data study, leaving 25

Test - retest reliability of two instruments for measuring public attitudes towards persons with mental illness

Directory of Open Access Journals (Sweden)

Leufstadius Christel

2011-01-01

Full Text Available Abstract Background Research has identified stigmatization as a major threat to successful treatment of individuals with mental illness. As a consequence several anti-stigma campaigns have been carried out. The results have been discouraging and the field suffers from lack of evidence about interventions that work. There are few reports on psychometric data for instruments used to assess stigma, which thus complicates research efforts. The aim of the present study was to investigate test-retest reliability of the Swedish versions of the questionnaires: FABI and "Changing Minds" and to examine the internal consistency of the two instruments. Method Two instruments, fear and behavioural intentions (FABI and "Changing Minds", used in earlier studies on public attitudes towards persons with mental illness were translated into Swedish and completed by 51 nursing students on two occasions, with an interval of three weeks. Test-retest reliability was calculated by using weighted kappa coefficient and internal consistency using the Cronbach's alpha coefficient. Results Both instruments attain at best moderate test-retest reliability. For the Changing Minds questionnaire almost one fifth (17.9% of the items present poor test-retest reliability and the alpha coefficient for the subscales ranges between 0.19 - 0.46. All of the items in the FABI reach a fair or a moderate agreement between the test and retest, and the questionnaire displays a high internal consistency, alpha 0.80. Conclusions There is a need for development of psychometrically tested instruments within this field of research.

Positron Emission Tomography studies with [11C]PBR28 in the Healthy Rodent Brain: Validating SUV as an Outcome Measure of Neuroinflammation.

Science.gov (United States)

Tóth, Miklós; Doorduin, Janine; Häggkvist, Jenny; Varrone, Andrea; Amini, Nahid; Halldin, Christer; Gulyás, Balázs

2015-01-01

Molecular imaging of the 18 kD Translocator protein (TSPO) with positron emission tomography (PET) is of great value for studying neuroinflammation in rodents longitudinally. Quantification of the TSPO in rodents is, however, quite challenging. There is no suitable reference region and the use of plasma-derived input is not an option for longitudinal studies. The aim of this study was therefore to evaluate the use of the standardized uptake value (SUV) as an outcome measure for TSPO imaging in rodent brain PET studies, using [11C]PBR28. In the first part of the study, healthy male Wistar rats (n = 4) were used to determine the correlation between the distribution volume (VT, calculated with Logan graphical analysis) and the SUV. In the second part, healthy male Wistar rats (n = 4) and healthy male C57BL/6J mice (n = 4), were used to determine the test-retest variability of the SUV, with a 7-day interval between measurements. Dynamic PET scans of 63 minutes were acquired with a nanoScan PET/MRI and nanoScan PET/CT. An MRI scan was made for anatomical reference with each measurement. The whole brain VT of [11C]PBR28 in rats was 42.9 ± 1.7. A statistically significant correlation (r2 = 0.96; p < 0.01) was found between the VT and the SUV. The test-retest variability in 8 brain region ranged from 8 to 20% in rats and from 7 to 23% in mice. The interclass correlation coefficient (ICC) was acceptable to excellent for rats, but poor to acceptable for mice. The SUV of [11C]PBR28 showed a high correlation with VT as well as good test-retest variability. For future longitudinal small animal PET studies the SUV can thus be used to describe [11C]PBR28 uptake in healthy brain tissue. Based on the present observations, further studies are needed to explore the applicability of this approach in small animal disease models, with special regard to neuroinflammatory models.

Imaging of striatal dopamine transporters in rat brain with single pinhole SPECT and co-aligned MRI is highly reproducible

International Nuclear Information System (INIS)

Booij, Jan; Bruin, Kora de; Win, Maartje M.L. de; Lavini, Cristina Mphil; Heeten, Gerard J. den; Habraken, Jan

2003-01-01

A recently developed pinhole high-resolution SPECT system was used to measure striatal to non-specific binding ratios in rats (n = 9), after injection of the dopamine transporter ligand 123 I-FP-CIT, and to assess its test/retest reproducibility. For co-alignment purposes, the rat brain was imaged on a 1.5 Tesla clinical MRI scanner using a specially developed surface coil. The SPECT images showed clear striatal uptake. On the MR images, cerebral and extra-cerebral structures could be easily delineated. The mean striatal to non-specific [ 123 I]FP-CIT binding ratios of the test/retest studies were 1.7 ± 0.2 and 1.6 ± 0.2, respectively. The test/retest variability was approximately 9%. We conclude that the assessment of striatal [ 123 I]FP-CIT binding ratios in rats is highly reproducible

Test-retest reliabilty of exercise-induced hypoalgesia after aerobic exercise

DEFF Research Database (Denmark)

Vaegter, Henrik Bjarke; Dørge, Daniel Bandholtz; Schmidt, Kristian Sonne

2018-01-01

Objective: Exercise increases pressure pain thresholds (PPTs) in exercising and nonexercising muscles, known as exercise-induced hypoalgesia (EIH). No studies have investigated the test-retest reliability of change in PPTs after aerobic exercise. Primary objectives were to compare the effect...

Test-retest reliability of Brazilian version of Memorial Symptom Assessment Scale for assessing symptoms in cancer patients.

Science.gov (United States)

Menezes, Josiane Roberta de; Luvisaro, Bianca Maria Oliveira; Rodrigues, Claudia Fernandes; Muzi, Camila Drumond; Guimarães, Raphael Mendonça

2017-01-01

To assess the test-retest reliability of the Memorial Symptom Assessment Scale translated and culturally adapted into Brazilian Portuguese. The scale was applied in an interview format for 190 patients with various cancers type hospitalized in clinical and surgical sectors of the Instituto Nacional de Câncer José de Alencar Gomes da Silva and reapplied in 58 patients. Data from the test-retest were double typed into a Microsoft Excel spreadsheet and analyzed by the weighted Kappa. The reliability of the scale was satisfactory in test-retest. The weighted Kappa values obtained for each scale item had to be adequate, the largest item was 0.96 and the lowest was 0.69. The Kappa subscale was also evaluated and values were 0.84 for high frequency physic symptoms, 0.81 for low frequency physical symptoms, 0.81 for psychological symptoms, and 0.78 for Global Distress Index. High level of reliability estimated suggests that the process of measurement of Memorial Symptom Assessment Scale aspects was adequate. Avaliar a confiabilidade teste-reteste da versão traduzida e adaptada culturalmente para o português do Brasil do Memorial Symptom Assessment Scale. A escala foi aplicada em forma de entrevista em 190 pacientes com diversos tipos de câncer internados nos setores clínicos e cirúrgicos do Instituto Nacional de Câncer José de Alencar Gomes da Silva e reaplicada em 58 pacientes. Os dados dos testes-retestes foram inseridos num banco de dados por dupla digitação independente em Excel e analisados pelo Kappa ponderado. A confiabilidade da escala mostrou-se satisfatória nos testes-retestes. Os valores do Kappa ponderado obtidos para cada item da escala apresentaram-se adequados, sendo o maior item de 0,96 e o menor de 0,69. Também se avaliou o Kappa das subescalas, sendo de 0,84 para sintomas físicos de alta frequência, de 0,81 para sintomas físicos de baixa frequência, de 0,81 também para sintomas psicológicos, e de 0,78 para Índice Geral de Sofrimento

(11)C-MK-8278 PET as a tool for pharmacodynamic brain occupancy of histamine 3 receptor inverse agonists.

Science.gov (United States)

Van Laere, Koenraad J; Sanabria-Bohórquez, Sandra M; Mozley, David P; Burns, Donald H; Hamill, Terence G; Van Hecken, Anne; De Lepeleire, Inge; Koole, Michel; Bormans, Guy; de Hoon, Jan; Depré, Marleen; Cerchio, Kristine; Plalcza, John; Han, Lingling; Renger, John; Hargreaves, Richard J; Iannone, Robert

2014-01-01

The histamine 3 (H3) receptor is a presynaptic autoreceptor in the central nervous system that regulates the synthesis and release of histamine and modulates the release of other major neurotransmitters. H3 receptor inverse agonists (IAs) may be efficacious in the treatment of various central nervous system disorders, including excessive daytime sleepiness, attention deficit hyperactivity disorder, Alzheimer disease, ethanol addiction, and obesity. Using PET and a novel high-affinity and selective radioligand (11)C-MK-8278, we studied the tracer biodistribution, quantification, and brain H3 receptor occupancy (RO) of MK-0249 and MK-3134, 2 potential IA drugs targeting cerebral H3 receptors, in 6 healthy male subjects (age, 19-40 y). The relationship among H3 IA dose, time on target, and peripheral pharmacokinetics was further investigated in 15 healthy male volunteers (age, 18-40 y) with up to 3 PET scans and 3 subjects per dose level. The mean effective dose for (11)C-MK-8278 was 5.4 ± 1.1 μSv/MBq. Human brain kinetics showed rapid high uptake and fast washout. Binding potential values can be assessed using the pons as a reference region, with a test-retest repeatability of 7%. Drug RO data showed low interindividual variability per dose (mean RO SD, 2.1%), and a targeted 90% RO can be reached for both IAs at clinically feasible doses. (11)C-MK-8278 is a useful novel PET radioligand for determination of human cerebral H3 receptor binding and allows highly reproducible in vivo brain occupancy of H3-targeting drugs, hereby enabling the evaluation of novel compounds in early development to select doses and schedules.

A reliability generalization meta-analysis of coefficient alpha and test-retest coefficient for the aging males' symptoms (AMS) scale.

Science.gov (United States)

Lee, Chin-Pang; Chiu, Yu-Wen; Chu, Chun-Lin; Chen, Yu; Jiang, Kun-Hao; Chen, Jiun-Liang; Chen, Ching-Yen

2016-12-01

The aging males' symptoms (AMS) scale is an instrument used to determine the health-related quality of life in adult and elderly men. The purpose of this study was to synthesize internal consistency (Cronbach's alpha) and test-retest reliability for the AMS scale and its three subscales. Of the 123 studies reviewed, 12 provided alpha coefficients which were then used in the meta-analyses of internal consistency. Seven of the 12 included studies provided test-retest coefficients, and these were used in the meta-analyses of test-retest reliability. The AMS scale had excellent internal consistency [α = 0.89 (95% CI 0.88-0.90)]; the mean alpha estimates across the AMS subscales ranged from 0.79 to 0.82. The AMS scale also had good test-retest reliability [r = 0.85 (95% CI 0.82-0.88]; the test-retest reliability coefficients of the AMS subscales ranged from 0.76 to 0.83. There was significant heterogeneity among the included studies. The AMS scale and the three subscales had fairly good internal consistency and test-retest reliability. Future psychometric studies of the AMS scale should report important characteristics of the participants, details of item scores, and test-retest reliability.

Atopy patch tests in young adult patients with atopic dermatitis and controls: dose-response relationship, objective reading, reproducibility and clinical interpretation.

Science.gov (United States)

Bygum, Anette; Mortz, Charlotte Gotthard; Andersen, Klaus Ejner

2003-01-01

The clinical interpretation and reproducibility of atopy patch tests was studied in 23 selected young adult patients with atopic dermatitis and 25 healthy controls using standard inhalant allergens. Non-invasive measurements were used for objective assessment of test reactions and the participants were retested after 6 weeks. Ten of 19 (53%) evaluable patients with atopic dermatitis had at least one positive atopy patch test. However, there was no clear clinical relevance of the atopy patch test results when related to patient history and distribution of dermatitis. Reproducible and dose-dependent results were obtained with Dermatophagoides pteronyssinus, grass and cat with a reproducibility rate of 0.69 to 0.81 in patients and 0.60-0.96 in controls. A unique finding was a significant positive correlation between a positive atopy patch test, allergen dose and increase in transepidermal water loss and erythema, while measurement of capacitance did not distinguish between positive and negative reactions. The results of the present study do not support the routine use of atopy patch tests in the evaluation of adult patients with atopic dermatitis.

Reproducibility assessment of brain responses to visual food stimuli in adults with overweight and obesity.

Science.gov (United States)

Drew Sayer, R; Tamer, Gregory G; Chen, Ningning; Tregellas, Jason R; Cornier, Marc-Andre; Kareken, David A; Talavage, Thomas M; McCrory, Megan A; Campbell, Wayne W

2016-10-01

The brain's reward system influences ingestive behavior and subsequently obesity risk. Functional magnetic resonance imaging (fMRI) is a common method for investigating brain reward function. This study sought to assess the reproducibility of fasting-state brain responses to visual food stimuli using BOLD fMRI. A priori brain regions of interest included bilateral insula, amygdala, orbitofrontal cortex, caudate, and putamen. Fasting-state fMRI and appetite assessments were completed by 28 women (n = 16) and men (n = 12) with overweight or obesity on 2 days. Reproducibility was assessed by comparing mean fasting-state brain responses and measuring test-retest reliability of these responses on the two testing days. Mean fasting-state brain responses on day 2 were reduced compared with day 1 in the left insula and right amygdala, but mean day 1 and day 2 responses were not different in the other regions of interest. With the exception of the left orbitofrontal cortex response (fair reliability), test-retest reliabilities of brain responses were poor or unreliable. fMRI-measured responses to visual food cues in adults with overweight or obesity show relatively good mean-level reproducibility but considerable within-subject variability. Poor test-retest reliability reduces the likelihood of observing true correlations and increases the necessary sample sizes for studies. © 2016 The Obesity Society.

Efficient and reproducible synthesis of [1-{sup 11}C]acetyl chloride using the loop method

Energy Technology Data Exchange (ETDEWEB)

Arai, Takuya [Department of Molecular Probes, Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Zhang, Ming-Rong [Department of Molecular Probes, Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)], E-mail: zhang@nirs.go.jp; Ogawa, Masanao [Department of Molecular Probes, Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); SHI Accelerator Service Co. Ltd., 1-17-6 Osaki, Shinagawa-ku, Tokyo 141-8686 (Japan); Fukumura, Toshimitsu; Kato, Koichi; Suzuki, Kazutoshi [Department of Molecular Probes, Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)

2009-02-15

[1-{sup 11}C]Acetyl chloride ([{sup 11}C]AcCl), an important [{sup 11}C]acylating agent, was synthesized by reacting [{sup 11}C]CO{sub 2} with methylmagnesium bromide coated on the inner surface of a polyethylene loop (loop method). By optimizing the reaction conditions and synthesis parameters, [1-{sup 11}C]phenylacetate and [1-{sup 11}C]benzylacetate were produced from [{sup 11}C]AcCl in high radiochemical yield and specific activity.

Maximal cardiorespiratory fitness testing in individuals with chronic stroke with cognitive impairment: practice test effects and test-retest reliability.

Science.gov (United States)

Olivier, Charles; Doré, Jean; Blanchet, Sophie; Brooks, Dina; Richards, Carol L; Martel, Guy; Robitaille, Nancy-Michelle; Maltais, Désirée B

2013-11-01

To evaluate, for individuals with chronic stroke with cognitive impairment, (1) the effects of a practice test on peak cardiorespiratory fitness test results; (2) cardiorespiratory fitness test-retest reliability; and (3) the relationship between individual practice test effects and cognitive impairment. Cross-sectional. Rehabilitation center. A convenience sample of 21 persons (men [n=12] and women [n=9]; age range, 48-81y; 44.9±36.2mo poststroke) with cognitive impairments who had sufficient lower limb function to perform the test. Not applicable. Peak oxygen consumption (Vo(2)peak, ml·kg(-1)·min(-1)). Test-retest reliability of Vo(2)peak was excellent (intraclass correlation coefficient model 2,1 [ICC2,1]=.94; 95% confidence interval [CI], .86-.98). A paired t test showed that there was no significant difference for the group for Vo(2)peak obtained from 2 symptom-limited cardiorespiratory fitness tests performed 1 week apart on a semirecumbent cycle ergometer (test 2-test 1 difference, -.32ml·kg(-1)·min(-1); 95% CI, -.69 to 1.33ml·kg(-1)·min(-1); P=.512). Individual test-retest differences in Vo(2)peak were, however, positively related to general cognitive function as measured by the Mini-Mental State Examination (ρ=.485; Preliably measured in this group without a practice test. General cognitive function, however, may influence the effect of a practice test in that those with lower general cognitive function appear to respond differently to a practice test than those with higher cognitive function. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Improving the Test-Retest Reliability of Resting State fMRI by Removing the Impact of Sleep.

Science.gov (United States)

Wang, Jiahui; Han, Junwei; Nguyen, Vinh T; Guo, Lei; Guo, Christine C

2017-01-01

Resting state functional magnetic resonance imaging (rs-fMRI) provides a powerful tool to examine large-scale neural networks in the human brain and their disturbances in neuropsychiatric disorders. Thanks to its low demand and high tolerance, resting state paradigms can be easily acquired from clinical population. However, due to the unconstrained nature, resting state paradigm is associated with excessive head movement and proneness to sleep. Consequently, the test-retest reliability of rs-fMRI measures is moderate at best, falling short of widespread use in the clinic. Here, we characterized the effect of sleep on the test-retest reliability of rs-fMRI. Using measures of heart rate variability (HRV) derived from simultaneous electrocardiogram (ECG) recording, we identified portions of fMRI data when subjects were more alert or sleepy, and examined their effects on the test-retest reliability of functional connectivity measures. When volumes of sleep were excluded, the reliability of rs-fMRI is significantly improved, and the improvement appears to be general across brain networks. The amount of improvement is robust with the removal of as much as 60% volumes of sleepiness. Therefore, test-retest reliability of rs-fMRI is affected by sleep and could be improved by excluding volumes of sleepiness as indexed by HRV. Our results suggest a novel and practical method to improve test-retest reliability of rs-fMRI measures.

A Test-Retest Reliability Study of the Whiplash Disability Questionnaire in Patients With Acute Whiplash-Associated Disorders

DEFF Research Database (Denmark)

Stupar, Maja; Côté, Pierre; Beaton, Dorcas E

2015-01-01

OBJECTIVE: The purpose of this study was to determine the test-retest reliability and the Minimal Detectable Change (MDC) of the Whiplash Disability Questionnaire (WDQ) in individuals with acute whiplash-associated disorders (WADs). METHODS: We performed a test-retest reliability study. We includ...

7 CFR 201.55 - Retests.

Science.gov (United States)

2010-01-01

... Germination Tests in the Administration of the Act § 201.55 Retests. Retests shall be made as follows: (a) When the range of 100-seed replicates of a given test exceeds the maximum tolerated range in the table... replicates of a given test, rounding off the result to the nearest whole number. The germination is found in...

Reproducibility of Tactile Assessments for Children with Unilateral Cerebral Palsy

Science.gov (United States)

Auld, Megan Louise; Ware, Robert S.; Boyd, Roslyn Nancy; Moseley, G. Lorimer; Johnston, Leanne Marie

2012-01-01

A systematic review identified tactile assessments used in children with cerebral palsy (CP), but their reproducibility is unknown. Sixteen children with unilateral CP and 31 typically developing children (TDC) were assessed 2-4 weeks apart. Test-retest percent agreements within one point for children with unilateral CP (and TDC) were…

Improving the Test-Retest Reliability of Resting State fMRI by Removing the Impact of Sleep

Directory of Open Access Journals (Sweden)

Jiahui Wang

2017-05-01

Full Text Available Resting state functional magnetic resonance imaging (rs-fMRI provides a powerful tool to examine large-scale neural networks in the human brain and their disturbances in neuropsychiatric disorders. Thanks to its low demand and high tolerance, resting state paradigms can be easily acquired from clinical population. However, due to the unconstrained nature, resting state paradigm is associated with excessive head movement and proneness to sleep. Consequently, the test-retest reliability of rs-fMRI measures is moderate at best, falling short of widespread use in the clinic. Here, we characterized the effect of sleep on the test-retest reliability of rs-fMRI. Using measures of heart rate variability (HRV derived from simultaneous electrocardiogram (ECG recording, we identified portions of fMRI data when subjects were more alert or sleepy, and examined their effects on the test-retest reliability of functional connectivity measures. When volumes of sleep were excluded, the reliability of rs-fMRI is significantly improved, and the improvement appears to be general across brain networks. The amount of improvement is robust with the removal of as much as 60% volumes of sleepiness. Therefore, test-retest reliability of rs-fMRI is affected by sleep and could be improved by excluding volumes of sleepiness as indexed by HRV. Our results suggest a novel and practical method to improve test-retest reliability of rs-fMRI measures.

Test-retest reliability and responsiveness of the Barthel Index-based Supplementary Scales in patients with stroke.

Science.gov (United States)

Lee, Ya-Chen; Yu, Wan-Hui; Hsueh, I-Ping; Chen, Sheng-Shiung; Hsieh, Ching-Lin

2017-10-01

A lack of evidence on the test-retest reliability and responsiveness limits the utility of the BI-based Supplementary Scales (BI-SS) in both clinical and research settings. To examine the test-retest reliability and responsiveness of the BI-based Supplementary Scales (BI-SS) in patients with stroke. A repeated-assessments design (1 week apart) was used to examine the test-retest reliability of the BI-SS. For the responsiveness study, the participants were assessed with the BI-SS and BI (treated as an external criterion) at admission to and discharge from rehabilitation wards. Seven outpatient rehabilitation units and one inpatient rehabilitation unit. Outpatients with chronic stroke. Eighty-four outpatients with chronic stroke participated in the test-retest reliability study. Fifty-seven inpatients completed baseline and follow-up assessments in the responsiveness study. For the test-retest reliability study, the values of the intra-class correlation coefficient and the overall percentage of minimal detectable change for the Ability Scale and Self-perceived Difficulty Scale were 0.97, 12.8%, and 0.78, 35.8%, respectively. For the responsiveness study, the standardized effect size and standardized response mean (representing internal responsiveness) of the Ability Scale and Self-perceived Difficulty Scale were 1.17 and 1.56, and 0.78 and 0.89, respectively. Regarding external responsiveness, the change in score of the Ability Scale had significant and moderate association with that of the BI (r=0.61, Ptest-retest reliability and sufficient responsiveness for patients with stroke. However, the Self-perceived Difficulty Scale of the BI-SS has substantial random measurement error and insufficient external responsiveness, which may affect its utility in clinical settings. The findings of this study provide empirical evidence of psychometric properties of the BI-SS for assessing ability and self-perceived difficulty of ADL in patients with stroke.

The test-retest reliability and criterion validity of a high-intensity, netball-specific circuit test: The Net-Test.

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Mungovan, Sean F; Peralta, Paula J; Gass, Gregory C; Scanlan, Aaron T

2018-04-12

To examine the test-retest reliability and criterion validity of a high-intensity, netball-specific fitness test. Repeated measures, within-subject design. Eighteen female netball players competing in an international competition completed a trial of the Net-Test, which consists of 14 timed netball-specific movements. Players also completed a series of netball-relevant criterion fitness tests. Ten players completed an additional Net-Test trial one week later to assess test-retest reliability using intraclass correlation coefficient (ICC), typical error of measurement (TEM), and coefficient of variation (CV). The typical error of estimate expressed as CV and Pearson correlations were calculated between each criterion test and Net-Test performance to assess criterion validity. Five movements during the Net-Test displayed moderate ICC (0.84-0.90) and two movements displayed high ICC (0.91-0.93). Seven movements and heart rate taken during the Net-Test held low CV (Test possessed low CV and significant (pTest possesses acceptable reliability for the assessment of netball fitness. Further, the high criterion validity for the Net-Test suggests a range of important netball-specific fitness elements are assessed in combination. Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

In vivo positron emission tomography imaging with [{sup 11}C]ABP688: binding variability and specificity for the metabotropic glutamate receptor subtype 5 in baboons

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DeLorenzo, Christine; Brennan, Kathleen G. [Columbia University College of Physicians and Surgeons, Division of Molecular Imaging and Neuropathology, Department of Psychiatry, NYSPI Mail Unit 42, New York, NY (United States); Milak, Matthew S.; Parsey, Ramin V. [Columbia University College of Physicians and Surgeons, Division of Molecular Imaging and Neuropathology, Department of Psychiatry, NYSPI Mail Unit 42, New York, NY (United States); New York State Psychiatric Institute, New York, NY (United States); Kumar, J.S.D.; Mann, J.J. [Columbia University College of Physicians and Surgeons, Division of Molecular Imaging and Neuropathology, Department of Psychiatry, NYSPI Mail Unit 42, New York, NY (United States); New York State Psychiatric Institute, New York, NY (United States); Columbia University College of Physicians and Surgeons, Department of Radiology, New York, NY (United States)

2011-06-15

Metabotropic glutamate receptor subtype 5 (mGluR5) dysfunction has been implicated in several disorders. [{sup 11}C]ABP688, a positron emission tomography (PET) ligand targeting mGluR5, could be a valuable tool in the development of novel therapeutics for these disorders by establishing in vivo drug occupancy. Due to safety concerns in humans, these studies may be performed in nonhuman primates. Therefore, in vivo characterization of [{sup 11}C]ABP688 in nonhuman primates is essential. Test-retest studies were performed in baboons (Papio anubis) to compare modeling approaches and determine the optimal reference region. The mGluR5-specific antagonist 3-((2-methyl-1,3-thiazol-4-yl)ethynyl)pyridine (MTEP) was then used in test-block studies, in which ligand binding was measured before and after MTEP administration. Test/block data were analyzed both by calculating changes in binding and using a graphical approach, which allowed estimation of both MTEP occupancy and nonspecific binding. Test-retest results, which have not been previously reported for [{sup 11}C]ABP688, indicated that [{sup 11}C]ABP688 variability is low using an unconstrained two-tissue compartment model. The most appropriate, though not ideal, reference region was found to be the gray matter of the cerebellum. Using these optimal modeling techniques on the test/block data, about 90% occupancy was estimated by the graphical approach. These studies are the first to demonstrate the specificity of [{sup 11}C]ABP688 for mGluR5 with in vivo PET in nonhuman primates. The results indicate that, in baboons, occupancy of mGluR5 is detectable by in vivo PET, a useful finding for proceeding to human studies, or performing further baboon studies, quantifying the in vivo occupancy of novel therapeutics targeting mGluR5. (orig.)

Evaluating the test-retest reliability of symptom indices associated with the ImPACT post-concussion symptom scale (PCSS).

Science.gov (United States)

Merritt, Victoria C; Bradson, Megan L; Meyer, Jessica E; Arnett, Peter A

2018-05-01

The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) is a commonly used tool in sports concussion assessment. While test-retest reliabilities have been established for the ImPACT cognitive composites, few studies have evaluated the psychometric properties of the ImPACT's Post-Concussion Symptom Scale (PCSS). The purpose of this study was to establish the test-retest reliability of symptom indices associated with the PCSS. Participants included 38 undergraduate students (50.0% male) who underwent neuropsychological testing as part of their participation in their psychology department's research subject pool. The majority of the participants were Caucasian (94.7%) and had no history of concussion (73.7%). All participants completed the ImPACT at two time points, approximately 6 weeks apart. The PCSS was the main outcome measure, and eight symptom indices were calculated (a total symptom score, three symptom summary indices, and four symptom clusters). Pearson correlations (r) and intraclass correlation coefficients (ICCs) were computed as measures of test-retest reliability. Overall, reliabilities ranged from low to high (r = .44 to .80; ICC = .44 to .77). The cognitive symptom cluster exhibited the highest test-retest reliability (r = .80, ICC = .77), followed by the positive symptom total (PST) index, an indicator of the total number of symptoms endorsed (r = .71, ICC = .69). In contrast, the commonly used total symptom score showed lower test-retest reliability (r = .67, ICC = .62). Paired-samples t tests revealed no significant differences between test and retest for any of the symptom variables (all p > .01). Finally, reliable change indices (RCI) were computed to determine whether differences observed between test and retest represented clinically significant change. RCI values were provided for each symptom index at the 80%, 90%, and 95% confidence intervals. These results suggest that evaluating additional symptom

Test-retest reliability of the eating disorder examination-questionnaire (EDE-Q) in a college sample

OpenAIRE

Rose, Jennifer S; Vaewsorn, Adin; Rosselli-Navarra, Francine; Wilson, G Terence; Weissman, Ruth Striegel

2013-01-01

Background The Eating Disorder Examination-Questionnaire (EDE-Q), a widely used self-report instrument, is often used for measuring change in eating disorder symptoms over the course of treatment. However, limited data exist about test-retest reliability, particularly for men. The current study evaluated EDE-Q 7-day test-retest reliability in male (n = 47) and female (n = 44) undergraduate students together and separately by gender. Results Internal consistency was consistently higher for wom...

Test-retest reliability and validity of a web-based food-frequency questionnaire for adolescents aged 13-14 to be used in the Norwegian Mother and Child Cohort Study (MoBa).

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Overby, Nina Cecilie; Johannesen, Elisabeth; Jensen, Grete; Skjaevesland, Anne-Kirsti; Haugen, Margaretha

2014-01-01

The assessment of food intake is challenging and prone to errors; it is therefore important to consider the reliability and validity of the assessment methods. The aim of this study was to analyze the reproducibility and validity of a developed food-frequency questionnaire (FFQ) for use among adolescents. In total, 58 students (aged 13-14) from four different schools in the southern part of Norway participated in the reproducibility study of filling out the FFQ 4 weeks apart. In addition, 93 students participated in the relative validity study where the FFQ was compared to 2×24-hour dietary recalls, while 92 students participated in the absolute validity study where the intakes of fatty acids and vitamin D from the FFQ were compared to fatty acids and 25-hydroxy-vitamin D3 in whole blood. The median Spearman correlation coefficient for all nutrients in the test-retest reliability study was 0.57. The median Spearman correlation for all nutrients in the relative validity study was 0.26, while the correlations coefficients were low in the absolute validity study with n-3 fatty acid coefficients ranging from 0.05 to 0.25, and absent for vitamin D (r=0.000). The test-retest reproducibility was considered good, the relative validity was considered poor to good, and the absolute validity was considered poor. However, the results are comparable to other studies among adolescents.

Learning effect and test-retest variability of pulsar perimetry.

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Salvetat, Maria Letizia; Zeppieri, Marco; Parisi, Lucia; Johnson, Chris A; Sampaolesi, Roberto; Brusini, Paolo

2013-03-01

To assess Pulsar Perimetry learning effect and test-retest variability (TRV) in normal (NORM), ocular hypertension (OHT), glaucomatous optic neuropathy (GON), and primary open-angle glaucoma (POAG) eyes. This multicenter prospective study included 43 NORM, 38 OHT, 33 GON, and 36 POAG patients. All patients underwent standard automated perimetry and Pulsar Contrast Perimetry using white stimuli modulated in phase and counterphase at 30 Hz (CP-T30W test). The learning effect and TRV for Pulsar Perimetry were assessed for 3 consecutive visual fields (VFs). The learning effect were evaluated by comparing results from the first session with the other 2. TRV was assessed by calculating the mean of the differences (in absolute value) between retests for each combination of single tests. TRV was calculated for Mean Sensitivity, Mean Defect, and single Mean Sensitivity for each 66 test locations. Influence of age, VF eccentricity, and loss severity on TRV were assessed using linear regression analysis and analysis of variance. The learning effect was not significant in any group (analysis of variance, P>0.05). TRV for Mean Sensitivity and Mean Defect was significantly lower in NORM and OHT (0.6 ± 0.5 spatial resolution contrast units) than in GON and POAG (0.9 ± 0.5 and 1.0 ± 0.8 spatial resolution contrast units, respectively) (Kruskal-Wallis test, P=0.04); however, the differences in NORM among age groups was not significant (Kruskal-Wallis test, P>0.05). Slight significant differences were found for the single Mean Sensitivity TRV among single locations (Duncan test, PPulsar Perimetry CP-T30W test did not show significant learning effect in patients with standard automated perimetry experience. TRV for global indices was generally low, and was not related to patient age; it was only slightly affected by VF defect eccentricity, and significantly influenced by VF loss severity.

Short-term test-retest-reliability of conditioned pain modulation using the cold-heat-pain method in healthy subjects and its correlation to parameters of standardized quantitative sensory testing.

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Gehling, Julia; Mainka, Tina; Vollert, Jan; Pogatzki-Zahn, Esther M; Maier, Christoph; Enax-Krumova, Elena K

2016-08-05

Conditioned Pain Modulation (CPM) is often used to assess human descending pain inhibition. Nine different studies on the test-retest-reliability of different CPM paradigms have been published, but none of them has investigated the commonly used heat-cold-pain method. The results vary widely and therefore, reliability measures cannot be extrapolated from one CPM paradigm to another. Aim of the present study was to analyse the test-retest-reliability of the common heat-cold-pain method and its correlation to pain thresholds. We tested the short-term test-retest-reliability within 40 ± 19.9 h using a cold-water immersion (10 °C, left hand) as conditioning stimulus (CS) and heat pain (43-49 °C, pain intensity 60 ± 5 on the 101-point numeric rating scale, right forearm) as test stimulus (TS) in 25 healthy right-handed subjects (12females, 31.6 ± 14.1 years). The TS was applied 30s before (TSbefore), during (TSduring) and after (TSafter) the 60s CS. The difference between the pain ratings for TSbefore and TSduring represents the early CPM-effect, between TSbefore and TSafter the late CPM-effect. Quantitative sensory testing (QST, DFNS protocol) was performed on both sessions before the CPM assessment. paired t-tests, Intraclass correlation coefficient (ICC), standard error of measurement (SEM), smallest real difference (SRD), Pearson's correlation, Bland-Altman analysis, significance level p Pain ratings during CPM correlated significantly (ICC: 0.411…0.962) between both days, though ratings for TSafter were lower on day 2 (p pain thresholds. The short-term test-retest-reliability of the early CPM-effect using the heat-cold-pain method in healthy subjects achieved satisfying results in terms of the ICC. The SRD of the early CPM effect showed that an individual change of > 20 NRS can be attributed to a real change rather than chance. The late CPM-effect was weaker and not reliable.

Test-Retest Reliability of the Preschool Age Psychiatric Assessment (PAPA)

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Egger, Helen Link; Erkanli, Alaattin; Keeler, Gordon; Potts, Edward; Walter, Barbara Keith; Angold, Adrian

2006-01-01

Objective: To examine the test-retest reliability of a new interviewer-based psychiatric diagnostic measure (the Preschool Age Psychiatric Assessment) for use with parents of preschoolers 2 to 5 years old. Method: A total of 1,073 parents of children attending a large pediatric clinic completed the Child Behavior Checklist 1 1/2-5. For 18 months,…

Test-retest reliability of speech-evoked auditory brainstem response in healthy children at a low sensation level.

Science.gov (United States)

Zakaria, Mohd Normani; Jalaei, Bahram

2017-11-01

Auditory brainstem responses evoked by complex stimuli such as speech syllables have been studied in normal subjects and subjects with compromised auditory functions. The stability of speech-evoked auditory brainstem response (speech-ABR) when tested over time has been reported but the literature is limited. The present study was carried out to determine the test-retest reliability of speech-ABR in healthy children at a low sensation level. Seventeen healthy children (6 boys, 11 girls) aged from 5 to 9 years (mean = 6.8 ± 3.3 years) were tested in two sessions separated by a 3-month period. The stimulus used was a 40-ms syllable /da/ presented at 30 dB sensation level. As revealed by pair t-test and intra-class correlation (ICC) analyses, peak latencies, peak amplitudes and composite onset measures of speech-ABR were found to be highly replicable. Compared to other parameters, higher ICC values were noted for peak latencies of speech-ABR. The present study was the first to report the test-retest reliability of speech-ABR recorded at low stimulation levels in healthy children. Due to its good stability, it can be used as an objective indicator for assessing the effectiveness of auditory rehabilitation in hearing-impaired children in future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Delineating a Retesting Zone Using Receiver Operating Characteristic Analysis on Serial QuantiFERON Tuberculosis Test Results in US Healthcare Workers

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Wendy Thanassi

2012-01-01

Full Text Available Objective. To find a statistically significant separation point for the QuantiFERON Gold In-Tube (QFT interferon gamma release assay that could define an optimal “retesting zone” for use in serially tested low-risk populations who have test “reversions” from initially positive to subsequently negative results. Method. Using receiver operating characteristic analysis (ROC to analyze retrospective data collected from 3 major hospitals, we searched for predictors of reversion until statistically significant separation points were revealed. A confirmatory regression analysis was performed on an additional sample. Results. In 575 initially positive US healthcare workers (HCWs, 300 (52.2% had reversions, while 275 (47.8% had two sequential positive tests. The most statistically significant (Kappa = 0.48, chi-square = 131.0, P<0.001 separation point identified by the ROC for predicting reversion was the tuberculosis antigen minus-nil (TBag-nil value at 1.11 International Units per milliliter (IU/mL. The second separation point was found at TBag-nil at 0.72 IU/mL (Kappa = 0.16, chi-square = 8.2, P<0.01. The model was validated by the regression analysis of 287 HCWs. Conclusion. Reversion likelihood increases as the TBag-nil approaches the manufacturer's cut-point of 0.35 IU/mL. The most statistically significant separation point between those who test repeatedly positive and those who revert is 1.11 IU/mL. Clinicians should retest low-risk individuals with initial QFT results < 1.11 IU/mL.

Short message service reminder intervention doubles sexually transmitted infection/HIV re-testing rates among men who have sex with men.

Science.gov (United States)

Bourne, C; Knight, V; Guy, R; Wand, H; Lu, H; McNulty, A

2011-04-01

To evaluate the impact of a short message service (SMS) reminder system on HIV/sexually transmitted infection (STI) re-testing rates among men who have sex with men (MSM). The SMS reminder programme started in late 2008 at a large Australian sexual health clinic. SMS reminders were recommended 3-6 monthly for MSM considered high-risk based on self-reported sexual behaviour. The evaluation compared HIV negative MSM who had a HIV/STI test between 1 January and 31 August 2010 and received a SMS reminder (SMS group) with those tested in the same time period (comparison group) and pre-SMS period (pre-SMS group, 1 January 2008 and 31 August 2008) who did not receive the SMS. HIV/STI re-testing rates were measured within 9 months for each group. Baseline characteristics were compared between study groups and multivariate logistic regression used to assess the association between SMS and re-testing and control for any imbalances in the study groups. There were 714 HIV negative MSM in the SMS group, 1084 in the comparison group and 1753 in the pre-SMS group. In the SMS group, 64% were re-tested within 9 months compared to 30% in the comparison group (preminders increased HIV/STI re-testing among HIV negative MSM. SMS offers a cheap, efficient system to increase HIV/STI re-testing in a busy clinical setting.

Testing Reproducibility in Earth Sciences

Science.gov (United States)

Church, M. A.; Dudill, A. R.; Frey, P.; Venditti, J. G.

2017-12-01

Reproducibility represents how closely the results of independent tests agree when undertaken using the same materials but different conditions of measurement, such as operator, equipment or laboratory. The concept of reproducibility is fundamental to the scientific method as it prevents the persistence of incorrect or biased results. Yet currently the production of scientific knowledge emphasizes rapid publication of previously unreported findings, a culture that has emerged from pressures related to hiring, publication criteria and funding requirements. Awareness and critique of the disconnect between how scientific research should be undertaken, and how it actually is conducted, has been prominent in biomedicine for over a decade, with the fields of economics and psychology more recently joining the conversation. The purpose of this presentation is to stimulate the conversation in earth sciences where, despite implicit evidence in widely accepted classifications, formal testing of reproducibility is rare.As a formal test of reproducibility, two sets of experiments were undertaken with the same experimental procedure, at the same scale, but in different laboratories. Using narrow, steep flumes and spherical glass beads, grain size sorting was examined by introducing fine sediment of varying size and quantity into a mobile coarse bed. The general setup was identical, including flume width and slope; however, there were some variations in the materials, construction and lab environment. Comparison of the results includes examination of the infiltration profiles, sediment mobility and transport characteristics. The physical phenomena were qualitatively reproduced but not quantitatively replicated. Reproduction of results encourages more robust research and reporting, and facilitates exploration of possible variations in data in various specific contexts. Following the lead of other fields, testing of reproducibility can be incentivized through changes to journal

Reliable set-up for in-loop 11C-carboxylations using Grignard reactions for the preparation of [carbonyl-11C]WAY-100635 and [11C]-(+)-PHNO

International Nuclear Information System (INIS)

Rami-Mark, Christina; Ungersboeck, Johanna; Haeusler, Daniela; Nics, Lukas; Philippe, Cecile; Mitterhauser, Markus; Willeit, Matthaeus; Lanzenberger, Rupert; Karanikas, Georgios; Wadsak, Wolfgang

2013-01-01

Aim of this work was the implementation of a generalized in-loop synthesis for 11 C-carboxylations and subsequent 11 C-acylations on the TRACERlab FxC Pro platform. The set-up was tested using [carbonyl- 11 C]WAY-100635 and, for the first time, [ 11 C]-(+)-PHNO. Its general applicability could be demonstrated and both [carbonyl- 11 C]WAY-100635 and [ 11 C]-(+)-PHNO were prepared with high reliability and satisfying outcome. - Highlights: • Generalized method for in-loop 11 C-carboxylations implemented. • Grignard reactions successfully tested. • First in-loop procedure for [ 11 C]-(+)PHNO established. • Satisfactory synthesis outcome for both [carbonyl- 11 C]WAY-100635 and [ 11 C]-(+)PHNO. • No distillation for purification of intermediate required

Test-retest, inter-assessor and intra-assessor reliability of the modified Touwen examination

NARCIS (Netherlands)

Peters, Lieke H. J.; Maathuis, Karel G. B.; Kouw, Eva; Hamming, Marjolein; Hadders-Algra, Mijna

Interest in the Touwen examination (1979) for the assessment of minor neurological dysfunction (MND) is growing. However, information on psychometric properties of this assessment is scarce. Therefore the present study aimed at assessing the test's test-retest, inter- and intra-assessor reliability.

Does an eye-hand coordination test have added value as part of talent identification in table tennis? A validity and reproducibility study.

Directory of Open Access Journals (Sweden)

Irene R Faber

Full Text Available This study investigated the added value, i.e. discriminative and concurrent validity and reproducibility, of an eye-hand coordination test relevant to table tennis as part of talent identification. Forty-three table tennis players (7-12 years from national (n = 13, regional (n = 11 and local training centres (n = 19 participated. During the eye-hand coordination test, children needed to throw a ball against a vertical positioned table tennis table with one hand and to catch the ball correctly with the other hand as frequently as possible in 30 seconds. Four different test versions were assessed varying the distance to the table (1 or 2 meter and using a tennis or table tennis ball. 'Within session' reproducibility was estimated for the two attempts of the initial tests and ten youngsters were retested after 4 weeks to estimate 'between sessions' reproducibility. Validity analyses using age as covariate showed that players from the national and regional centres scored significantly higher than players from the local centre in all test versions (p<0.05. The tests at 1 meter demonstrated better discriminative ability than those at 2 meter. While all tests but one had a positive significant association with competition outcome, which were corrected for age influences, the version with a table tennis ball at 1 meter showed the highest association (r = 0.54; p = 0.001. Differences between the first and second attempts were comparable for all test versions (between -8 and +7 repetitions with ICC's ranging from 0.72 to 0.87. The smallest differences were found for the test with a table tennis ball at 1 meter (between -3 and +3 repetitions. Best test version as part of talent identification appears to be the version with a table tennis ball at 1 meter regarding the psychometric characteristics evaluated. Longitudinal studies are necessary to evaluate the predictive value of this test.

Development, test-retest reliability, and construct validity of the resistance training skills battery.

Science.gov (United States)

Lubans, David R; Smith, Jordan J; Harries, Simon K; Barnett, Lisa M; Faigenbaum, Avery D

2014-05-01

The aim of this study was to describe the development and assess test-retest reliability and construct validity of the Resistance Training Skills Battery (RTSB) for adolescents. The RTSB provides an assessment of resistance training skill competency and includes 6 exercises (i.e., body weight squat, push-up, lunge, suspended row, standing overhead press, and front support with chest touches). Scoring for each skill is based on the number of performance criteria successfully demonstrated. An overall resistance training skill quotient (RTSQ) is created by adding participants' scores for the 6 skills. Participants (44 boys and 19 girls, mean age = 14.5 ± 1.2 years) completed the RTSB on 2 occasions separated by 7 days. Participants also completed the following fitness tests, which were used to create a muscular fitness score (MFS): handgrip strength, timed push-up, and standing long jump tests. Intraclass correlation (ICC), paired samples t-tests, and typical error were used to assess test-retest reliability. To assess construct validity, gender and RTSQ were entered into a regression model predicting MFS. The rank order repeatability of the RTSQ was high (ICC = 0.88). The model explained 39% of the variance in MFS (p ≤ 0.001) and RTSQ (r = 0.40, p ≤ 0.001) was a significant predictor. This study has demonstrated the construct validity and test-retest reliability of the RTSB in a sample of adolescents. The RTSB can reliably rank participants in regards to their resistance training competency and has the necessary sensitivity to detect small changes in resistance training skill proficiency.

Test-Retest Reliability of Rating of Perceived Exertion and Agreement With 1-Repetition Maximum in Adults.

Science.gov (United States)

Bove, Allyn M; Lynch, Andrew D; DePaul, Samantha M; Terhorst, Lauren; Irrgang, James J; Fitzgerald, G Kelley

2016-09-01

Study Design Clinical measurement. Background It has been suggested that rating of perceived exertion (RPE) may be a useful alternative to 1-repetition maximum (1RM) to determine proper resistance exercise dosage. However, the test-retest reliability of RPE for resistance exercise has not been determined. Additionally, prior research regarding the relationship between 1RM and RPE is conflicting. Objectives The purpose of this study was to (1) determine test-retest reliability of RPE related to resistance exercise and (2) assess agreement between percentages of 1RM and RPE during quadriceps resistance exercise. Methods A sample of participants with and without knee pathology completed a series of knee extension exercises and rated the perceived difficulty of each exercise on a 0-to-10 RPE scale, then repeated the procedure 1 to 2 weeks later for test-retest reliability. To determine agreement between RPE and 1RM, participants completed knee extension exercises at various percentages of their 1RM (10% to 130% of predicted 1RM) and rated the perceived difficulty of each exercise on a 0-to-10 RPE scale. Percent agreement was calculated between the 1RM and RPE at each resistance interval. Results The intraclass correlation coefficient indicated excellent test-retest reliability of RPE for quadriceps resistance exercises (intraclass correlation coefficient = 0.895; 95% confidence interval: 0.866, 0.918). Overall percent agreement between RPE and 1RM was 60%, but agreement was poor within the ranges that would typically be used for training (50% 1RM for muscle endurance, 70% 1RM and greater for strength). Conclusion Test-retest reliability of perceived exertion during quadriceps resistance exercise was excellent. However, agreement between the RPE and 1RM was poor, especially in common training zones for knee extensor strengthening. J Orthop Sports Phys Ther 2016;46(9):768-774. Epub 5 Aug 2016. doi:10.2519/jospt.2016.6498.

The Physical Activity Scale for Individuals with Physical Disabilities: test-retest reliability and comparison with an accelerometer.

Science.gov (United States)

van der Ploeg, Hidde P; Streppel, Kitty R M; van der Beek, Allard J; van der Woude, Luc H V; Vollenbroek-Hutten, Miriam; van Mechelen, Willem

2007-01-01

The objective was to determine the test-retest reliability and criterion validity of the Physical Activity Scale for Individuals with Physical Disabilities (PASIPD). Forty-five non-wheelchair dependent subjects were recruited from three Dutch rehabilitation centers. Subjects' diagnoses were: stroke, spinal cord injury, whiplash, and neurological-, orthopedic- or back disorders. The PASIPD is a 7-d recall physical activity questionnaire that was completed twice, 1 wk apart. During this week, physical activity was also measured with an Actigraph accelerometer. The test-retest reliability Spearman correlation of the PASIPD was 0.77. The criterion validity Spearman correlation was 0.30 when compared to the accelerometer. The PASIPD had test-retest reliability and criterion validity that is comparable to well established self-report physical activity questionnaires from the general population.

Dual conception of risk in the Iowa Gambling Task: Effects of sleep deprivation and test-retest gap

Directory of Open Access Journals (Sweden)

Varsha eSingh

2013-09-01

Full Text Available Risk in the Iowa Gambling Task (IGT is often understood in terms of intertemporal choices, i.e., preference for immediate outcomes in favor of delayed outcomes is considered risky. According to behavioral economics, decision makers refrain from choosing the short-sighted immediate gain because, over time (10 trials, the immediate gains result in a net loss. Instead decision makers are expected to maximize their gains by choosing options that, over time (10 trials, result in net gain. However, task choices are sometimes made on the basis of the frequency of reward and punishment such that infrequent punishments are favored over frequent punishments. The presence of these two attributes (intertemporality and frequency may correspond to the emotion-cognition dichotomy and reflect a dual conception of risk. Decision making on the basis of the two attributes was tested under two conditions: test-retest gap and sleep deprivation. An interaction between these two was expected to attenuate the difference between the two attributes (n=40 male. Analysis of the effects of IGT attribute type (intertemporal vs. frequency, sleep deprivation (sleep deprivation vs. no sleep deprivation, and test-retest gap (short vs. long showed a significant effect of IGT attribute type thus confirming the difference between the two attributes. Sleep deprivation had no effect on the attributes, but test-retest gap and the three-way interaction between attribute type, test-retest gap, and sleep deprivation were significant. Post-hoc tests showed sleep deprivation and short test-retest gap to attenuate the difference between the two attributes. As expected intertemporal decision making benefited from repeated task exposure. The findings add to understanding of the emotion-cognition dichotomy and show a time-dependent effect of a universally experienced constraint (sleep deprivation.

Test-retest reliability of Eurofit Physical Fitness items for children with visual impairments

NARCIS (Netherlands)

Houwen, Suzanne; Visscher, Chris; Hartman, Esther; Lemmink, Koen A. P. M.

The purpose of this study was to examine the test-retest reliability of physical fitness items from the European Test of Physical Fitness (Eurofit) for children with visual impairments. A sample of 21 children, ages 6-12 years, that were recruited from a special school for children with visual

Test-Retest Reliability and Practice Effects of the Stability Evaluation Test.

Science.gov (United States)

Williams, Richelle M; Corvo, Matthew A; Lam, Kenneth C; Williams, Travis A; Gilmer, Lesley K; McLeod, Tamara C Valovich

2017-01-17

Postural control plays an essential role in concussion evaluation. The Stability Evaluation Test (SET) aims to objectively analyze postural control by measuring sway velocity on the NeuroCom's VSR portable force platform (Natus, San Carlos, CA). To assess the test-retest reliability and practice effects of the SET protocol. Cohort. Research Laboratory. Fifty healthy adults (males=20, females=30, age=25.30±3.60 years, height=166.60±12.80 cm, mass=68.80±13.90 kg). All participants completed four trials of the SET. Each trial consisted of six 20-second balance tests with eyes closed, under the following conditions: double-leg firm (DFi), single-leg firm (SFi), tandem firm (TFi), double-leg foam (DFo), single-leg foam (SFo), and tandem foam (TFo). Each trial was separated by a 5-minute seated rest period. The dependent variable was sway velocity (deg/sec), with lower values indicating better balance. Sway velocity was recorded for each of the six conditions as well as a composite score for each trial. Test-retest reliability was analyzed across four trials with Intraclass Correlation Coefficients. Practice effects analyzed with repeated measures analysis of variance, followed by Tukey post-hoc comparisons for any significant main effects (preliability values were good to excellent: DFi (ICC=0.88;95%CI:0.81,0.92), SFi (ICC=0.75;95%CI:0.61,0.85), TFi (ICC=0.84;95%CI:0.75,0.90), DFo (ICC=0.83;95%CI:0.74,0.90), SFo (ICC=0.82;95%CI:0.72,0.89), TFo (ICC=0.81;95%CI:0.69,0.88), and composite score (ICC=0.93;95%CI:0.88,0.95). Significant practice effects (preliability for the assessment of postural control in healthy adults. Due to the practice effects noted, a familiarization session is recommended (i.e., all 6 conditions) prior to recording the data. Future studies should evaluate injured patients to determine meaningful change scores during various injuries.

Test-retest reliability of the Battery for the Assessment of Auditory Sensorimotor and Timing Abilities (BAASTA).

Science.gov (United States)

Bégel, Valentin; Verga, Laura; Benoit, Charles-Etienne; Kotz, Sonja A; Bella, Simone Dalla

2018-04-27

Perceptual and sensorimotor timing skills can be comprehensively assessed with the Battery for the Assessment of Auditory Sensorimotor and Timing Abilities (BAASTA). The battery has been used for testing rhythmic skills in healthy adults and patient populations (e.g., with Parkinson disease), showing sensitivity to timing and rhythm deficits. Here we assessed the test-retest reliability of the BAASTA in 20 healthy adults. Participants were tested twice with the BAASTA, implemented on a tablet interface, with a 2-week interval. They completed 4 perceptual tasks, namely, duration discrimination, anisochrony detection with tones and music, and the Beat Alignment Test (BAT). Moreover, they completed motor tasks via finger tapping, including unpaced and paced tapping with tones and music, synchronization-continuation, and adaptive tapping to a sequence with a tempo change. Despite high variability among individuals, the results showed stable test-retest reliability in most tasks. A slight but significant improvement from test to retest was found in tapping with music, which may reflect a learning effect. In general, the BAASTA was found a reliable tool for evaluating timing and rhythm skills. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Test-retest reliability of the 20-sec Wingate test to assess anaerobic power in children with cerebral palsy

NARCIS (Netherlands)

Dallmeijer, A.J.; Scholtes, V.A.B.; Brehm, M.A.; Becher, J.G.

2013-01-01

OBJECTIVE: The aim of this study was to determine the test-retest reliability of the 20-sec Wingate anaerobic test in children with cerebral palsy. DESIGN: Participants were 22 ambulant children with cerebral palsy, with Gross Motor Function Classification System levels I (limitations in advanced

Test-Retest Reliability of the 20-sec Wingate Test to Assess Anaerobic Power in Children with Cerebral Palsy

NARCIS (Netherlands)

Dallmeijer, Annet J.; Scholtes, Vanessa A. B.; Brehm, Merel-Anne; Becher, Jules G.

2013-01-01

Objective: The aim of this study was to determine the test-retest reliability of the 20-sec Wingate anaerobic test in children with cerebral palsy. Design: Participants were 22 ambulant children with cerebral palsy, with Gross Motor Function Classification System levels I (limitations in advanced

Dual conception of risk in the Iowa Gambling Task: effects of sleep deprivation and test-retest gap.

Science.gov (United States)

Singh, Varsha

2013-01-01

Risk in the Iowa Gambling Task (IGT) is often understood in terms of intertemporal choices, i.e., preference for immediate outcomes in favor of delayed outcomes is considered risky decision making. According to behavioral economics, healthy decision makers are expected to refrain from choosing the short-sighted immediate gain because, over time (10 trials of the IGT), the immediate gains result in a long term loss (net loss). Instead decision makers are expected to maximize their gains by choosing options that, over time (10 trials), result in delayed or long term gains (net gain). However, task choices are sometimes made on the basis of the frequency of reward and punishment such that frequent rewards/infrequent punishments are favored over infrequent rewards/frequent punishments. The presence of these two attributes (intertemporality and frequency of reward) in IGT decision making may correspond to the emotion-cognition dichotomy and reflect a dual conception of risk. Decision making on the basis of the two attributes was tested under two conditions: delay in retest and sleep deprivation. An interaction between sleep deprivation and time delay was expected to attenuate the difference between the two attributes. Participants were 40 male university students. Analysis of the effects of IGT attribute type (intertemporal vs. frequency of reinforcement), sleep deprivation (sleep deprivation vs. no sleep deprivation), and test-retest gap (short vs. long delay) showed a significant within-subjects effect of IGT attribute type thus confirming the difference between the two attributes. Sleep deprivation had no effect on the attributes, but test-retest gap and the three-way interaction between attribute type, test-retest gap, and sleep deprivation were significantly different. Post-hoc tests revealed that sleep deprivation and short test-retest gap attenuated the difference between the two attributes. Furthermore, the results showed an expected trend of increase in

Intensity response function of the photopic negative response (PhNR): effect of age and test-retest reliability.

Science.gov (United States)

Joshi, Nabin R; Ly, Emma; Viswanathan, Suresh

2017-08-01

To assess the effect of age and test-retest reliability of the intensity response function of the full-field photopic negative response (PhNR) in normal healthy human subjects. Full-field electroretinograms (ERGs) were recorded from one eye of 45 subjects, and 39 of these subjects were tested on two separate days with a Diagnosys Espion System (Lowell, MA, USA). The visual stimuli consisted of brief (test-retest reliability was assessed with the Wilcoxon signed-rank test and Bland-Altman analysis. Holm's correction was applied to account for multiple comparisons. V max of BT was significantly smaller than that of PT and b-wave, and the V max of PT and b-wave was not significantly different from each other. The slope parameter n was smallest for BT and the largest for b-wave and the difference between the slopes of all three measures were statistically significant. Small differences observed in the mean values of K for the different measures did not reach statistical significance. The Wilcoxon signed-rank test indicated no significant differences between the two test visits for any of the Naka-Rushton parameters for the three ERG measures, and the Bland-Altman plots indicated that the mean difference between test and retest measurements of the different fit parameters was close to zero and within 6% of the average of the test and retest values of the respective parameters for all three ERG measurements, indicating minimal bias. While the coefficient of reliability (COR, defined as 1.96 times the standard deviation of the test and retest difference) of each fit parameter was more or less comparable across the three ERG measurements, the %COR (COR normalized to the mean test and retest measures) was generally larger for BT compared to both PT and b-wave for each fit parameter. The Naka-Rushton fit parameters did not show statistically significant changes with age for any of the ERG measures when corrections were applied for multiple comparisons. However, the V max of

Adaptation, test-retest reliability, and construct validity of the Physical Activity Neighborhood Environment Scale in Nigeria (PANES-N).

Science.gov (United States)

Oyeyemi, Adewale L; Sallis, James F; Oyeyemi, Adetoyeje Y; Amin, Mariam M; De Bourdeaudhuij, Ilse; Deforche, Benedicte

2013-11-01

This study adapted the Physical Activity Neighborhood Environment Scale (PANES) to the Nigerian context and assessed the test-retest reliability and construct validity of the Nigerian version (PANESN). A multidisciplinary panel of experts adapted the original PANES to reflect the built and social environment of Nigeria. The adapted PANES was subjected to cognitive testing and test retest reliability in a diverse sample of Nigerian adults (N = 132) from different neighborhood types. Intraclass Correlation Coefficients (ICC) was used to assess test-retest reliability, and construct validity was investigated with Analysis of Covariance for differences in environmental attributes between neighborhoods. Four of the 17 items on the original PANES were significantly modified, 3 were removed and 2 new items were incorporated into the final version of adapted PANES-N. Test-retest reliability was substantial to almost perfect (ICC = 0.62-1.00) for all items on the PANES-N, and residents of neighborhoods in the inner city reported higher residential density, land use mix and safety, but lower pedestrian facilities and aesthetics than did residents of government reserved area/new layout neighborhoods. The PANES-N appears promising for assessing environmental perceptions related to physical activity in Nigeria, but further testing is required to assess its applicability across Africa.

Brain Serotonin Transporter Binding In a Minipig Model of Parkinson's Disease

DEFF Research Database (Denmark)

Lillethorup, Thea Pinholt; Glud, Andreas Nørgaard; Sørensen, Jens Christian Hedemann

minipigs were implanted in the cisterna magna with a catheter connected to a subcutaneous titanium injection port under sterile conditions. Six-eight weeks after recovery from the catheter implant, and after injections of sterile saline alone to verify patency, minipigs were scanned at baseline with [11C......]-3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl)-benzonitrile (11C-DASB), a label of SERT availability. Four pigs then received eight weekly injections of lactacystin dissolved in sterile saline, and one pig received saline alone, directly into the CSF through the access port. They were scanned...... with DASB again after a cumulative dose of 200μg lactacystin. PET data were registered to an average minipig MRI atlas and processed using PMOD software. The binding potential (BPND) of DASB was obtained with the Logan graphical analysis and cerebellum activity as a region of non-displaceable binding...

Reproducibility of a reaming test

DEFF Research Database (Denmark)

Pilny, Lukas; Müller, Pavel; De Chiffre, Leonardo

2012-01-01

The reproducibility of a reaming test was analysed to document its applicability as a performance test for cutting fluids. Reaming tests were carried out on a drilling machine using HSS reamers. Workpiece material was an austenitic stainless steel, machined using 4.75 m∙min-1 cutting speed and 0......). Process reproducibility was assessed as the ability of different operators to ensure a consistent rating of individual lubricants. Absolute average values as well as experimental standard deviations of the evaluation parameters were calculated, and uncertainty budgeting was performed. Results document...... a built-up edge occurrence hindering a robust evaluation of cutting fluid performance, if the data evaluation is based on surface finish only. Measurements of hole geometry provide documentation to recognize systematic error distorting the performance test....

Reproducibility of a reaming test

DEFF Research Database (Denmark)

Pilny, Lukas; Müller, Pavel; De Chiffre, Leonardo

2014-01-01

The reproducibility of a reaming test was analysed to document its applicability as a performance test for cutting fluids. Reaming tests were carried out on a drilling machine using HSS reamers. Workpiece material was an austenitic stainless steel, machined using 4.75 m•min−1 cutting speed and 0......). Process reproducibility was assessed as the ability of different operators to ensure a consistent rating of individual lubricants. Absolute average values as well as experimental standard deviations of the evaluation parameters were calculated, and uncertainty budgeting was performed. Results document...... a built–up edge occurrence hindering a robust evaluation of cutting fluid performance, if the data evaluation is based on surface finish only. Measurements of hole geometry provide documentation to recognise systematic error distorting the performance test....

Tumor imaging with PET and C-11 thymidine

International Nuclear Information System (INIS)

Conti, P.S.; Hilton, J.; Magee, C.A.; Anderson, J.H.

1989-01-01

Accurate interpretation of kinetic positron-emission tomographic (PET) data obtained following administration of C-11 thymidine requires identification of radiolabeled metabolites. The authors goal is to quantitate rapidly formed metabolites of C-11 thymidine by using reproducible high-pressure liquid chromatography (HPLC). Following coinjection of methyl-C-11 and methyl-C-14 thymidine, dogs bearing implanted glioblastoma were imaged with PET. Plasma samples were collected, and dogs were sacrificed at 60 minutes. Tissues were prepared for quantitative autoradiography and analysis of radioactivity associated with DNA, RNA protein, and acid soluble extracts. Plasma and tissue extracts were analyzed by HPLC by using C-18 reverse phase and dilute buffer mobile phase systems for the separation of catabolites and phosphorylated nucleotides

Test-retest reliability and cross validation of the functioning everyday with a wheelchair instrument.

Science.gov (United States)

Mills, Tamara L; Holm, Margo B; Schmeler, Mark

2007-01-01

The purpose of this study was to establish the test-retest reliability and content validity of an outcomes tool designed to measure the effectiveness of seating-mobility interventions on the functional performance of individuals who use wheelchairs or scooters as their primary seating-mobility device. The instrument, Functioning Everyday With a Wheelchair (FEW), is a questionnaire designed to measure perceived user function related to wheelchair/scooter use. Using consumer-generated items, FEW Beta Version 1.0 was developed and test-retest reliability was established. Cross-validation of FEW Beta Version 1.0 was then carried out with five samples of seating-mobility users to establish content validity. Based on the content validity study, FEW Version 2.0 was developed and administered to seating-mobility consumers to examine its test-retest reliability. FEW Beta Version 1.0 yielded an intraclass correlation coefficient (ICC) Model (3,k) of .92, p content validity results revealed that FEW Beta Version 1.0 captured 55% of seating-mobility goals reported by consumers across five samples. FEW Version 2.0 yielded ICC(3,k) = .86, p content validity of FEW Version 2.0 was confirmed. FEW Beta Version 1.0 and FEW Version 2.0 were highly stable in their measurement of participants' seating-mobility goals over a 1-week interval.

The test-retest reliability of the latent construct of executive function depends on whether tasks are represented as formative or reflective indicators.

Science.gov (United States)

Willoughby, Michael T; Kuhn, Laura J; Blair, Clancy B; Samek, Anya; List, John A

2017-10-01

This study investigates the test-retest reliability of a battery of executive function (EF) tasks with a specific interest in testing whether the method that is used to create a battery-wide score would result in differences in the apparent test-retest reliability of children's performance. A total of 188 4-year-olds completed a battery of computerized EF tasks twice across a period of approximately two weeks. Two different approaches were used to create a score that indexed children's overall performance on the battery-i.e., (1) the mean score of all completed tasks and (2) a factor score estimate which used confirmatory factor analysis (CFA). Pearson and intra-class correlations were used to investigate the test-retest reliability of individual EF tasks, as well as an overall battery score. Consistent with previous studies, the test-retest reliability of individual tasks was modest (rs ≈ .60). The test-retest reliability of the overall battery scores differed depending on the scoring approach (r mean  = .72; r factor_ score  = .99). It is concluded that the children's performance on individual EF tasks exhibit modest levels of test-retest reliability. This underscores the importance of administering multiple tasks and aggregating performance across these tasks in order to improve precision of measurement. However, the specific strategy that is used has a large impact on the apparent test-retest reliability of the overall score. These results replicate our earlier findings and provide additional cautionary evidence against the routine use of factor analytic approaches for representing individual performance across a battery of EF tasks.

Enzymatic synthesis of C-11 formaldehyde: concise communication

International Nuclear Information System (INIS)

Slegers, G.; Lambrecht, R.H.D.; Vandewalle, T.; Meulewaeter, L.; Vandecasteele, C.

1984-01-01

An enzymatic synthesis of C-11 formaldehyde from C-11 methanol is presented, with immobilized alcohol oxidase and catalase: a rapid, simple procedure, with a high and reproducible yield. Carbon-11 methanol is oxidized to C-11 formaldehyde by passage over a column on which the enzymes alcohol oxidase and catalase are immobilized. The catalase increases reaction velocity by recycling the oxygen, and prevents destruction of the alcohol oxidase by eliminating the excess of hydrogen peroxide. The yield of the enzyme-catalyzed oxidation was 80-95%. A specific activity of 400-450 mCi/μmole was obtained at EOB + 20 min. Various immobilization techniques and the optimal reaction conditions of the immobilized enzymes are investigated

Questionnaire for measuring organisational attributes in dental-care practices: psychometric properties and test-retest reliability.

Science.gov (United States)

Goetz, Katja; Hasse, Philipp; Szecsenyi, Joachim; Campbell, Stephen M

2016-04-01

The consideration of organisational aspects, such as shared goals and clear communication, within the health care team is important to ensure good quality care. In primary health care, the instrument Survey of Organizational Attributes for Primary Care (SOAPC) is available to measure organisational attributes of care. However, there is no instrument available for dental care. The aim of the present study was to investigate psychometric properties and test-retest reliability of the version of SOAPC adapted for dental care, namely the Survey of Organizational Attributes in Dental Care (SOADC). The SOADC consists of 21 items in the following four subscales: communication; decision making; stress/chaos; and history of change. Convergent construct validity was measured using the job satisfaction scale. A total of 287 dental-care practices were asked to participate in the validation study. Psychometric properties and test-retest reliability were observed. A total of 43 dental-care practices responded to the survey. At baseline, 178 dental-care staff completed the questionnaire, and 4 weeks later 138 did so. Internal consistency, measured by Cronbach's alpha, was 0.718 or higher in the subscales. The test-retest reliability for each subscale and the overall SOADC score demonstrated good correlations over the 4-week test-retest interval, except for 'history of change'. A strong correlation with the aggregated job-satisfaction scale showed high convergent construct validity of SOADC. The consideration of organisational aspects from the perspective of dental-care teams is important for providing good quality of care. The SOADC is a reliable instrument with good psychometric properties and is suitable for the evaluation of organisational attributes in dental-care practices. © 2015 FDI World Dental Federation.

Test-Retest Reliability of a Serious Game for Delirium Screening in the Emergency Department.

Science.gov (United States)

Tong, Tiffany; Chignell, Mark; Tierney, Mary C; Lee, Jacques S

2016-01-01

Introduction: Cognitive screening in settings such as emergency departments (ED) is frequently carried out using paper-and-pencil tests that require administration by trained staff. These assessments often compete with other clinical duties and thus may not be routinely administered in these busy settings. Literature has shown that the presence of cognitive impairments such as dementia and delirium are often missed in older ED patients. Failure to recognize delirium can have devastating consequences including increased mortality (Kakuma et al., 2003). Given the demands on emergency staff, an automated cognitive test to screen for delirium onset could be a valuable tool to support delirium prevention and management. In earlier research we examined the concurrent validity of a serious game, and carried out an initial assessment of its potential as a delirium screening tool (Tong et al., 2016). In this paper, we examine the test-retest reliability of the game, as it is an important criterion in a cognitive test for detecting risk of delirium onset. Objective: To demonstrate the test-retest reliability of the screening tool over time in a clinical sample of older emergency patients. A secondary objective is to assess whether there are practice effects that might make game performance unstable over repeated presentations. Materials and Methods: Adults over the age of 70 were recruited from a hospital ED. Each patient played our serious game in an initial session soon after they arrived in the ED, and in follow up sessions conducted at 8-h intervals (for each participant there were up to five follow up sessions, depending on how long the person stayed in the ED). Results: A total of 114 adults (61 females, 53 males) between the ages of 70 and 104 years ( M = 81 years, SD = 7) participated in our study after screening out delirious patients. We observed a test-retest reliability of the serious game (as assessed by correlation r -values) between 0.5 and 0.8 across adjacent

Stability of FDG-PET Radiomics features - An integrated analysis of test-retest and inter-observer variability

Energy Technology Data Exchange (ETDEWEB)

Leijenaar, Ralph T. H.; Carvalho, Sara; Rios Velazquez, Emmanuel [Dept. of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht Univ. Medical Center, Maastricht (Netherlands)] [and others

2013-10-15

Purpose: Besides basic measurements as maximum standardized uptake value (SUV){sub max} or SUV{sub mean} derived from 18F-FDG positron emission tomography (PET) scans, more advanced quantitative imaging features (i.e. 'Radiomics' features) are increasingly investigated for treatment monitoring, outcome prediction, or as potential biomarkers. With these prospected applications of Radiomics features, it is a requisite that they provide robust and reliable measurements. The aim of our study was therefore to perform an integrated stability analysis of a large number of PET-derived features in non-small cell lung carcinoma (NSCLC), based on both a test-retest and an inter-observer setup. Methods: Eleven NSCLC patients were included in the test-retest cohort. Patients underwent repeated PET imaging within a one day interval, before any treatment was delivered. Lesions were delineated by applying a threshold of 50 % of the maximum uptake value within the tumor. Twenty-three NSCLC patients were included in the inter-observer cohort. Patients underwent a diagnostic whole body PET-computed tomography (CT). Lesions were manually delineated based on fused PET-CT, using a standardized clinical delineation protocol. Delineation was performed independently by five observers, blinded to each other. Fifteen first order statistics, 39 descriptors of intensity volume histograms, eight geometric features and 44 textural features were extracted. For every feature, test-retest and inter-observer stability was assessed with the intra-class correlation coefficient (ICC) and the coefficient of variability, normalized to mean and range. Similarity between test-retest and inter-observer stability rankings of features was assessed with Spear man's rank correlation coefficient. Results: Results showed that the majority of assessed features had both a high test-retest (71%) and inter-observer (91%) stability in terms of their ICC. Overall, features more stable in repeated PET

Test-retest reliability of the isernhagen work systems functional capacity evaluation in healthy adults

NARCIS (Netherlands)

Reneman, MF; Brouwer, S; Meinema, A; Dijkstra, PU; Geertzen, JHB; Groothoff, JW

2004-01-01

Aim of this study was to investigate test-retest reliability of the Isernhagen Work System Functional Capacity Evaluation (IWS FCE) in healthy subjects. The IWS FCE consists of 28 tests that reflect work-related activities such as lifting, carrying, bending, etc. A convenience sample of 26 healthy

Test-retest reliability and stability of N400 effects in a word-pair semantic priming paradigm.

Science.gov (United States)

Kiang, Michael; Patriciu, Iulia; Roy, Carolyn; Christensen, Bruce K; Zipursky, Robert B

2013-04-01

Elicited by any meaningful stimulus, the N400 event-related potential (ERP) component is reduced when the stimulus is related to a preceding one. This N400 semantic priming effect has been used to probe abnormal semantic relationship processing in clinical disorders, and suggested as a possible biomarker for treatment studies. Validating N400 semantic priming effects as a clinical biomarker requires characterizing their test-retest reliability. We assessed test-retest reliability of N400 semantic priming in 16 healthy adults who viewed the same related and unrelated prime-target word pairs in two sessions one week apart. As expected, N400 amplitudes were smaller for related versus unrelated targets across sessions. N400 priming effects (amplitude differences between unrelated and related targets) were highly correlated across sessions (r=0.85, Pmotivational changes. Use of N400 priming effects in treatment studies should account for possible magnitude decreases with repeat testing. Further research is needed to delineate N400 priming effects' test-retest reliability and stability in different age and clinical groups, and with different stimulus types. Copyright © 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Reliability of Autism-Tics, AD/HD, and other Comorbidities (A-TAC) inventory in a test-retest design.

Science.gov (United States)

Larson, Tomas; Kerekes, Nóra; Selinus, Eva Norén; Lichtenstein, Paul; Gumpert, Clara Hellner; Anckarsäter, Henrik; Nilsson, Thomas; Lundström, Sebastian

2014-02-01

The Autism-Tics, AD/HD, and other Comorbidities (A-TAC) inventory is used in epidemiological research to assess neurodevelopmental problems and coexisting conditions. Although the A-TAC has been applied in various populations, data on retest reliability are limited. The objective of the present study was to present additional reliability data. The A-TAC was administered by lay assessors and was completed on two occasions by parents of 400 individual twins, with an average interval of 70 days between test sessions. Intra- and inter-rater reliability were analysed with intraclass correlations and Cohen's kappa. A-TAC showed excellent test-retest intraclass correlations for both autism spectrum disorder and attention deficit hyperactivity disorder (each at .84). Most modules in the A-TAC had intra- and inter-rater reliability intraclass correlation coefficients of > or = .60. Cohen's kappa indi- cated acceptable reliability. The current study provides statistical evidence that the A-TAC yields good test-retest reliability in a population-based cohort of children.

Reproducibility of an aerobic endurance test for nonexpert swimmers.

Science.gov (United States)

Veronese da Costa, Adalberto; Costa, Manoel da Cunha; Carlos, Daniel Medeiros; Guerra, Luis Marcos de Medeiros; Silva, Antônio José; Barbosa, Tiago Manoel Cabral Dos Santos

2012-01-01

This study aimed to verify the reproduction of an aerobic test to determine nonexpert swimmers' resistance. The sample consisted of 24 male swimmers (age: 22.79 ± 3.90 years; weight: 74.72 ± 11.44 kg; height: 172.58 ± 4.99 cm; and fat percentage: 15.19% ± 3.21%), who swim for 1 hour three times a week. A new instrument was used in this study (a Progressive Swim Test): the swimmer wore an underwater MP3 player and increased their swimming speed on hearing a beep after every 25 meters. Each swimmer's heart rate was recorded before the test (BHR) and again after the test (AHR). The rate of perceived exertion (RPE) and the number of laps performed (NLP) were also recorded. The sample size was estimated using G*Power software (v 3.0.10; Franz Faul, Kiel University, Kiel, Germany). The descriptive values were expressed as mean and standard deviation. After confirming the normality of the data using both the Shapiro-Wilk and Levene tests, a paired t-test was performed to compare the data. The Pearson's linear correlation (r) and intraclass coefficient correlation (ICC) tests were used to determine relative reproducibility. The standard error of measurement (SEM) and the coefficient of variation (CV) were used to determine absolute reproducibility. The limits of agreement and the bias of the absolute and relative values between days were determined by Bland-Altman plots. All values had a significance level of P 0.50 and ICC > 0.66. The SEM had a variation of ±2% and the CV was 0.90; SEM swimmers. The Progressive Swim Test for nonexpert swimmers produces comparable results for noncompetitive swimmers with a favorable degree of reproducibility, thus presenting possible applications for researching the physiological performance of nonexpert swimmers.

Test-Retest Reliability of Diffusion Tensor Imaging in Huntington's Disease.

Science.gov (United States)

Cole, James H; Farmer, Ruth E; Rees, Elin M; Johnson, Hans J; Frost, Chris; Scahill, Rachael I; Hobbs, Nicola Z

2014-03-21

Diffusion tensor imaging (DTI) has shown microstructural abnormalities in patients with Huntington's Disease (HD) and work is underway to characterise how these abnormalities change with disease progression. Using methods that will be applied in longitudinal research, we sought to establish the reliability of DTI in early HD patients and controls. Test-retest reliability, quantified using the intraclass correlation coefficient (ICC), was assessed using region-of-interest (ROI)-based white matter atlas and voxelwise approaches on repeat scan data from 22 participants (10 early HD, 12 controls). T1 data was used to generate further ROIs for analysis in a reduced sample of 18 participants. The results suggest that fractional anisotropy (FA) and other diffusivity metrics are generally highly reliable, with ICCs indicating considerably lower within-subject compared to between-subject variability in both HD patients and controls. Where ICC was low, particularly for the diffusivity measures in the caudate and putamen, this was partly influenced by outliers. The analysis suggests that the specific DTI methods used here are appropriate for cross-sectional research in HD, and give confidence that they can also be applied longitudinally, although this requires further investigation. An important caveat for DTI studies is that test-retest reliability may not be evenly distributed throughout the brain whereby highly anisotropic white matter regions tended to show lower relative within-subject variability than other white or grey matter regions.

Reproducibility of the chamber scarification test

DEFF Research Database (Denmark)

Andersen, Klaus Ejner

1996-01-01

The chamber scarification test is a predictive human skin irritation test developed to rank the irritation potential of products and ingredients meant for repeated use on normal and diseased skin. 12 products or ingredients can be tested simultaneously on the forearm skin of each volunteer....... The test combines with the procedure scratching of the skin at each test site and subsequent closed patch tests with the products, repeated daily for 3 days. The test is performed on groups of human volunteers: a skin irritant substance or products is included in each test as a positive control...... high reproducibility of the test. Further, intra-individual variation in skin reaction to the 2 control products in 26 volunteers, who participated 2x, is shown, which supports the conclusion that the chamber scarification test is a useful short-term human skin irritation test with high reproducibility....

Test-retest reliability of handgrip strength measurement using a hydraulic hand dynamometer in patients with cervical radiculopathy.

Science.gov (United States)

Savva, Christos; Giakas, Giannis; Efstathiou, Michalis; Karagiannis, Christos

2014-01-01

The purpose of this study was to evaluate the test-retest reliability of handgrip strength measurement using a hydraulic hand dynamometer in patients with cervical radiculopathy (CR). A convenience sample of 19 participants (14 men and 5 women; mean ± SD age, 50.5 ± 12 years) with CR was measured using a Jamar hydraulic hand dynamometer by the same rater on 2 different testing sessions with an interval of 7 days between sessions. Data collection procedures followed standardized grip strength testing guidelines established by the American Society of Hand Therapists. During the repeated measures, patients were advised to rest their upper limb in the standardized arm position and encouraged to exert 3 maximum gripping efforts. The mean value of the 3 efforts (measured in kilogram force [Kgf]) was used for data analysis. The intraclass correlation coefficient, SEM, and the Bland-Altman plot were used to estimate test-retest reliability and measurement precision. Grip strength measurement in CR demonstrated an intraclass correlation coefficient of 0.976, suggesting excellent test-retest reliability. The small SEM in both testing sessions (SEM1, 2.41 Kgf; SEM2, 2.51 Kgf) as well as the narrow width of the 95% limits of agreements (95% limits of agreement, -4.9 to 4.4 Kgf) in the Bland-Altman plot reflected precise measurements of grip strength in both occasions. Excellent test-retest reliability for grip strength measurement was measured in patients with CR, demonstrating that a hydraulic hand dynamometer could be used as an outcome measure for these patients. Copyright © 2014 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

Test-Retest Reliability of Dual-Task Outcome Measures in People With Parkinson Disease

NARCIS (Netherlands)

Strouwen, C.; Molenaar, E.A.; Keus, S.H.; Munks, L.; Bloem, B.R.; Nieuwboer, A.

2016-01-01

BACKGROUND: Dual-task (DT) training is gaining ground as a physical therapy intervention in people with Parkinson disease (PD). Future studies evaluating the effect of such interventions need reliable outcome measures. To date, the test-retest reliability of DT measures in patients with PD remains

Validity and test-retest reliability of a novel simple back extensor muscle strength test.

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Harding, Amy T; Weeks, Benjamin Kurt; Horan, Sean A; Little, Andrew; Watson, Steven L; Beck, Belinda Ruth

2017-01-01

To develop and determine convergent validity and reliability of a simple and inexpensive clinical test to quantify back extensor muscle strength. Two testing sessions were conducted, 7 days apart. Each session involved three trials of standing maximal isometric back extensor muscle strength using both the novel test and isokinetic dynamometry. Lumbar spine bone mineral density was examined by dual-energy X-ray absorptiometry. Validation was examined with Pearson correlations ( r ). Test-retest reliability was examined with intraclass correlation coefficients and limits of agreement. Pearson correlations and intraclass correlation coefficients are presented with corresponding 95% confidence intervals. Linear regression was used to examine the ability of peak back extensor muscle strength to predict indices of lumbar spine bone mineral density and strength. A total of 52 healthy adults (26 men, 26 women) aged 46.4 ± 20.4 years were recruited from the community. A strong positive relationship was observed between peak back extensor strength from hand-held and isokinetic dynamometry ( r  = 0.824, p  strength test, short- and long-term reliability was excellent (intraclass correlation coefficient = 0.983 (95% confidence interval, 0.971-0.990), p  strength measures with the novel back extensor strength protocol were -6.63 to 7.70 kg, with a mean bias of +0.71 kg. Back extensor strength predicted 11% of variance in lumbar spine bone mineral density ( p  strength ( p  strength is quick, relatively inexpensive, and reliable; demonstrates initial convergent validity in a healthy population; and is associated with bone mass at a clinically important site.

Test-retest reliability of Physical Activity Neighborhood Environment Scale among urban men and women in Nanjing, China.

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Zhao, L; Wang, Z; Qin, Z; Leslie, E; He, J; Xiong, Y; Xu, F

2018-03-01

The identification of physical-activity-friendly built environment (BE) constructs is highly useful for physical activity promotion and maintenance. The Physical Activity Neighborhood Environment Scale (PANES) was developed for assessing BE correlates. However, PANES reliability has not been investigated among adults in China. A cross-sectional study. With multistage sampling approaches, 1568 urban adults (aged 35-74 years) were recruited for the initial survey on all 17 items of PANES Chinese version (PANES-CHN), with the survey repeated 7 days later for each participant. Intraclass correlation coefficient (ICC) was used to assess the test-retest reliability of PANES-CHN for each item. Totally, 1551 participants completed both surveys (follow-up rate = 98.9%). Among participants (mean age: 54.7 ± 11.1 years), 47.8% were men, 22.1% were elders, and 22.7% had ≥13 years of education. Overall, the PANES-CHN demonstrated at least substantial reliability with ICCs ranging from 0.66 to 0.95 (core items), from 0.75 to 0.95 (recommended items), and from 0.78 to 0.87 (optional items). Similar outcomes were observed when data were analyzed by gender or age groups. The PANES-CHN has excellent test-retest reliability and thus has valuable utility for assessing urban BE attributes among Chinese adults. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

The intersubject and intrasubject reproducibility of FMRI activation during three encoding tasks: implications for clinical applications

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Harrington, Greg S.; Tomaszewski Farias, Sarah; Buonocore, Michael H.; Yonelinas, Andrew P.

2006-01-01

The goal of the present study was to evaluate the inter- and intrasubject reproducibility of FMRI activation for three memory encoding tasks previously used in the context of presurgical functional mapping. The primary region of interest (ROI) was the medial temporal lobe (MTL). Comparative ROIs included the inferior frontal and fusiform gyri which are less affected by susceptibility-induced signal losses than the MTL regions. Eighteen subjects were scanned using three memory encoding paradigms: word-pair, pattern, and scene encoding. Nine subjects underwent repeat scanning. Intersubject reproducibility of FMRI activation was evaluated by examining the percent of subjects who showed activation within a given ROI and the range to which individual laterality indices (LIs) varied from the mean. Intrasubject test-retest reproducibility was evaluated by examining the LI test-retest correlation, the average difference between LIs from two separate imaging sessions, and concordance ratios of activation volumes (R volume and R overlap ). For scene encoding the reproducibility of activation volume and LIs within the MTL were as good as or better than the reproducibility within the fusiform and inferior frontal ROIs. For pattern encoding and word-pair encoding, the reproducibility of activation volume and LIs within the MTL tended to be worse compared to the fusiform and inferior frontal ROIs. The differences in FMRI reproducibility appeared more dependent on the task than the susceptibility effects. The results of this study suggest that FMRI-based assessment of the neural substrates of memory using a scene encoding task may be a useful clinical tool. (orig.)

The intersubject and intrasubject reproducibility of FMRI activation during three encoding tasks: implications for clinical applications

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Harrington, Greg S. [Virginia Commonwealth University, Department of Radiology, Richmond, VA (United States); Tomaszewski Farias, Sarah [University of California at Davis, Department of Neurology, Sacramento (United States); Buonocore, Michael H. [University of California at Davis, Department of Radiology, Sacramento (United States); Yonelinas, Andrew P. [University of California at Davis, Department of Psychology, Davis (United States)

2006-07-15

The goal of the present study was to evaluate the inter- and intrasubject reproducibility of FMRI activation for three memory encoding tasks previously used in the context of presurgical functional mapping. The primary region of interest (ROI) was the medial temporal lobe (MTL). Comparative ROIs included the inferior frontal and fusiform gyri which are less affected by susceptibility-induced signal losses than the MTL regions. Eighteen subjects were scanned using three memory encoding paradigms: word-pair, pattern, and scene encoding. Nine subjects underwent repeat scanning. Intersubject reproducibility of FMRI activation was evaluated by examining the percent of subjects who showed activation within a given ROI and the range to which individual laterality indices (LIs) varied from the mean. Intrasubject test-retest reproducibility was evaluated by examining the LI test-retest correlation, the average difference between LIs from two separate imaging sessions, and concordance ratios of activation volumes (R{sub volume} and R{sub overlap}). For scene encoding the reproducibility of activation volume and LIs within the MTL were as good as or better than the reproducibility within the fusiform and inferior frontal ROIs. For pattern encoding and word-pair encoding, the reproducibility of activation volume and LIs within the MTL tended to be worse compared to the fusiform and inferior frontal ROIs. The differences in FMRI reproducibility appeared more dependent on the task than the susceptibility effects. The results of this study suggest that FMRI-based assessment of the neural substrates of memory using a scene encoding task may be a useful clinical tool. (orig.)

Development of an Agility Test for Badminton Players and Assessment of Its Validity and Test-Retest Reliability.

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Loureiro, Luiz de França Bahia; de Freitas, Paulo Barbosa

2016-04-01

Badminton requires open and fast actions toward the shuttlecock, but there is no specific agility test for badminton players with specific movements. To develop an agility test that simultaneously assesses perception and motor capacity and examine the test's concurrent and construct validity and its test-retest reliability. The Badcamp agility test consists of running as fast as possible to 6 targets placed on the corners and middle points of a rectangular area (5.6 × 4.2 m) from the start position located in the center of it, following visual stimuli presented in a luminous panel. The authors recruited 43 badminton players (17-32 y old) to evaluate concurrent (with shuttle-run agility test--SRAT) and construct validity and test-retest reliability. Results revealed that Badcamp presents concurrent and construct validity, as its performance is strongly related to SRAT (ρ = 0.83, P < .001), with performance of experts being better than nonexpert players (P < .01). In addition, Badcamp is reliable, as no difference (P = .07) and a high intraclass correlation (ICC = .93) were found in the performance of the players on 2 different occasions. The findings indicate that Badcamp is an effective, valid, and reliable tool to measure agility, allowing coaches and athletic trainers to evaluate players' athletic condition and training effectiveness and possibly detect talented individuals in this sport.

Putaminal serotonergic innervation: monitoring dyskinesia risk in Parkinson disease.

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Lee, Jee-Young; Seo, Seongho; Lee, Jae Sung; Kim, Han-Joon; Kim, Yu Kyeong; Jeon, Beom S

2015-09-08

To explore serotonergic innervation in the basal ganglia in relation to levodopa-induced dyskinesia in patients with Parkinson disease (PD). A total of 30 patients with PD without dementia or depression were divided into 3 matched groups (dyskinetic, nondyskinetic, and drug-naive) for this study. We acquired 2 PET scans and 3T MRI for each patient using [(11)C]-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)-benzonitrile ((11)C-DASB) and N-(3-[(18)F]fluoropropyl)-2-carbomethoxy-3-(4-iodophenyl) nortropane ((18)F-FP-CIT). Then we analyzed binding potentials of the 2 radiotracers at basal ganglia structures and correlations with clinical variables. We observed no difference in (18)F-FP-CIT binding between dyskinetic and nondyskinetic patients, whereas there were differences in (11)C-DASB binding for the caudate and putamen. Binding potential ratios ((11)C-DASB/(18)F-FP-CIT) at the putamen, which indicate serotoninergic fiber innervation relative to dopaminergic fiber availability, were highest in the dyskinetic group, followed by the nondyskinetic and drug-naive PD groups. (11)C-DASB/(18)F-FP-CIT ratios at the putamen and pallidum correlated positively with Unified Parkinson's Disease Rating Scale (UPDRS) total scores and duration of PD, and pallidal binding ratio also correlated with the UPDRS motor scores. Ratios were not dependent on dopaminergic medication dosages for any of the regions studied. Relative serotonergic innervation of the putamen and pallidum increased with clinical PD progression and was highest in patients with established dyskinesia. The serotonin/dopamine transporter ratio might be a potential marker of disease progression and an indicator of risk for levodopa-induced dyskinesia in PD. A prospective evaluation is warranted in the future. © 2015 American Academy of Neurology.

Oxytocin effects on emotional response to others' faces via serotonin system in autism: A pilot study.

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Fukai, Mina; Hirosawa, Tetsu; Kikuchi, Mitsuru; Ouchi, Yasuomi; Takahashi, Tetsuya; Yoshimura, Yuko; Miyagishi, Yoshiaki; Kosaka, Hirotaka; Yokokura, Masamichi; Yoshikawa, Etsuji; Bunai, Tomoyasu; Minabe, Yoshio

2017-09-30

The oxytocin (OT)-related serotonergic system is thought to play an important role in the etiology and social symptoms of autism spectrum disorder (ASD). However, no evidence exists for the relation between the prosocial effect of chronic OT administration and the brain serotonergic system. Ten male subjects with ASD were administered OT for 8-10 weeks in an open-label, single-arm, non-randomized, uncontrolled manner. Before and during the OT treatment, positron emission tomography was used with the ( 11 C)-3-amino-4-(2-[(demethylamino)methyl]phenylthio)benzonitrile( 11 C-DASB) radiotracer. Then binding of serotonin transporter ( 11 C-DASB BP ND ) was estimated. The main outcome measures were changes in 11 C-DASB BP ND and changes in the emotional response to others' faces. No significant change was found in the emotional response to others' faces after the 8-10 week OT treatment. However, the increased serotonin transporter (SERT) level in the striatum after treatment was correlated significantly with increased negative emotional response to human faces. This study revealed a relation between changes in the serotonergic system and in prosociality after chronic OT administration. Additional studies must be conducted to verify the chronic OT effects on social behavior via the serotonergic system. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Test-retest reliability of barbell velocity during the free-weight bench-press exercise.

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Stock, Matt S; Beck, Travis W; DeFreitas, Jason M; Dillon, Michael A

2011-01-01

The purpose of this study was to calculate test-retest reliability statistics for peak barbell velocity during the free-weight bench-press exercise for loads corresponding to 10-90% of the 1-repetition maximum (1RM). Twenty-one healthy, resistance-trained men (mean ± SD age = 23.5 ± 2.7 years; body mass = 90.5 ± 14.6 kg; 1RM bench press = 125.4 ± 18.4 kg) volunteered for this study. A minimum of 48 hours after a maximal strength testing and familiarization session, the subjects performed single repetitions of the free-weight bench-press exercise at each tenth percentile (10-90%) of the 1RM on 2 separate occasions. For each repetition, the subjects were instructed to press the barbell as rapidly as possible, and peak barbell velocity was measured with a Tendo Weightlifting Analyzer. The test-retest intraclass correlation coefficients (model 2,1) and corresponding standard errors of measurement (expressed as percentages of the mean barbell velocity values) were 0.717 (4.2%), 0.572 (5.0%), 0.805 (3.1%), 0.669 (4.7%), 0.790 (4.6%), 0.785 (4.8%), 0.811 (5.8%), 0.714 (10.3%), and 0.594 (12.6%) for the weights corresponding to 10-90% 1RM. There were no mean differences between the barbell velocity values from trials 1 and 2. These results indicated moderate to high test-retest reliability for barbell velocity from 10 to 70% 1RM but decreased consistency at 80 and 90% 1RM. When examining barbell velocity during the free-weight bench-press exercise, greater measurement error must be overcome at 80 and 90% 1RM to be confident that an observed change is meaningful.

Reproducibility of R-fMRI metrics on the impact of different strategies for multiple comparison correction and sample sizes.

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Chen, Xiao; Lu, Bin; Yan, Chao-Gan

2018-01-01

Concerns regarding reproducibility of resting-state functional magnetic resonance imaging (R-fMRI) findings have been raised. Little is known about how to operationally define R-fMRI reproducibility and to what extent it is affected by multiple comparison correction strategies and sample size. We comprehensively assessed two aspects of reproducibility, test-retest reliability and replicability, on widely used R-fMRI metrics in both between-subject contrasts of sex differences and within-subject comparisons of eyes-open and eyes-closed (EOEC) conditions. We noted permutation test with Threshold-Free Cluster Enhancement (TFCE), a strict multiple comparison correction strategy, reached the best balance between family-wise error rate (under 5%) and test-retest reliability/replicability (e.g., 0.68 for test-retest reliability and 0.25 for replicability of amplitude of low-frequency fluctuations (ALFF) for between-subject sex differences, 0.49 for replicability of ALFF for within-subject EOEC differences). Although R-fMRI indices attained moderate reliabilities, they replicated poorly in distinct datasets (replicability < 0.3 for between-subject sex differences, < 0.5 for within-subject EOEC differences). By randomly drawing different sample sizes from a single site, we found reliability, sensitivity and positive predictive value (PPV) rose as sample size increased. Small sample sizes (e.g., < 80 [40 per group]) not only minimized power (sensitivity < 2%), but also decreased the likelihood that significant results reflect "true" effects (PPV < 0.26) in sex differences. Our findings have implications for how to select multiple comparison correction strategies and highlight the importance of sufficiently large sample sizes in R-fMRI studies to enhance reproducibility. Hum Brain Mapp 39:300-318, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Confiabilidade teste-reteste de aspectos da rede social no Estudo Pró-Saúde Test-retest reliability of measures of social network in the "Pró-Saúde" Study

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Rosane Harter Griep

2003-06-01

Full Text Available OBJETIVO: Avaliar os níveis de confiabilidade teste-reteste de informações relativas à rede social no Estudo Pró-saúde. MÉTODOS: Foi estimada a confiabilidade pelo estudo teste-reteste por meio de questionário multidimensional aplicado a uma coorte de trabalhadores de uma universidade. O mesmo questionário foi preenchido duas vezes por 192 funcionários não efetivos da universidade, com duas semanas de intervalo entre as aplicações. A concordância foi estimada pela estatística Kappa (variáveis categóricas, estatística Kappa ponderado e modelos log-lineares (variáveis ordinais, e coeficiente de correlação intraclasse (variáveis discretas. RESULTADOS: As medidas de concordância situaram-se acima de 0,70 para a maioria das variáveis. Estratificando-se as informações segundo gênero, idade e escolaridade, observou-se que a confiabilidade não apresentou padrão consistente de variabilidade. A aplicação de modelos log-lineares indicou que, para as variáveis ordinais do estudo, o modelo de melhor ajuste foi o de "concordância diagonal mais associação linear por linear". CONCLUSÕES: Os altos níveis de confiabilidade estimados permitem concluir que o processo de aferição dos itens sobre rede social foi adequado para as características investigadas. Estudos de validação em andamento complementarão a avaliação da qualidade dessas informações.OBJECTIVE: To evaluate test-retest reliability of social network-related information of the" Pró-Saúde" study. METHODS: A test-retest reliability study was conducted using a multidimensional questionnaire applied to a cohort of university employees. The same questionnaire was filled out twice by 192 non-permanent employees with two weeks apart. Agreement was estimated using kappa statistics (categorical variables, weighted kappa statistics, log-linear models (ordinal variables, and intraclass correlation coefficient (discrete variables. RESULTS: Estimates of reliability

Kinetic analysis of [11C]vorozole binding in the human brain with positron emission tomography.

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Logan, Jean; Kim, Sung Won; Pareto, Deborah; Telang, Frank; Wang, Gene-Jack; Fowler, Joanna S; Biegon, Anat

2014-01-01

Using positron emission tomography, we investigated the kinetics of [11C]vorozole ([11C]VOR), a radiotracer for the enzyme aromatase that catalyzes the last step in estrogen biosynthesis. Six subjects were scanned under baseline conditions followed by retest 2 weeks later. The retest was followed by a blocking study with 2.5 mg of the aromatase inhibitor letrozole. The binding potential (BP(A)ND) was estimated from a Lassen plot using the total tissue distribution volume (VT) for baseline and blocked. for the thalamus was found to be 15 times higher than that for the cerebellum. From the letrozole studies, we found that [11C]VOR exhibits a slow binding compartment (small k4) that has a nonspecific and a blockable component. Because of the sensitivity of VT to variations in k4, a common value was used for the four highest binding regions. We also considered the tissue uptake to plasma ratio for 60 to 90 minutes as an outcome measure. Using the ratio method, the difference between the highest and lowest was 2.4 compared to 3.5 for the VT. The ratio method underestimates the high regions but is less variable and may be more suitable for patient studies. Because of its kinetics and distribution, this tracer is not a candidate for a bolus infusion or reference tissue methods.

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

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Gronbech Jorgensen, Martin; Andersen, Stig; Ryg, Jesper; Masud, Tahir

2015-01-01

Portable, 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. The 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. A 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. No 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. A 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.

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

Directory of Open Access Journals (Sweden)

Martin Gronbech Jorgensen

Full Text Available Portable, 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.The 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.A 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.No 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.A 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.

Test–Retest Reliability of Measures Commonly Used to Measure Striatal Dysfunction across Multiple Testing Sessions: A Longitudinal Study

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Clare E. Palmer

2018-01-01

Full Text Available Cognitive impairment is common amongst many neurodegenerative movement disorders such as Huntington’s disease (HD and Parkinson’s disease (PD across multiple domains. There are many tasks available to assess different aspects of this dysfunction, however, it is imperative that these show high test–retest reliability if they are to be used to track disease progression or response to treatment in patient populations. Moreover, in order to ensure effects of practice across testing sessions are not misconstrued as clinical improvement in clinical trials, tasks which are particularly vulnerable to practice effects need to be highlighted. In this study we evaluated test–retest reliability in mean performance across three testing sessions of four tasks that are commonly used to measure cognitive dysfunction associated with striatal impairment: a combined Simon Stop-Signal Task; a modified emotion recognition task; a circle tracing task; and the trail making task. Practice effects were seen between sessions 1 and 2 across all tasks for the majority of dependent variables, particularly reaction time variables; some, but not all, diminished in the third session. Good test–retest reliability across all sessions was seen for the emotion recognition, circle tracing, and trail making test. The Simon interference effect and stop-signal reaction time (SSRT from the combined-Simon-Stop-Signal task showed moderate test–retest reliability, however, the combined SSRT interference effect showed poor test–retest reliability. Our results emphasize the need to use control groups when tracking clinical progression or use pre-baseline training on tasks susceptible to practice effects.

Test-Retest Reliability of Self-Reported Sexual Health Measures among US Hispanic Adolescents

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Jerman, Petra; Berglas, Nancy F.; Rohrbach, Louise A.; Constantine, Norman A.

2016-01-01

Objective: Although Hispanic adolescents in the USA are often the focus of sexual health interventions, their response to survey measures has rarely been assessed within evaluation studies. This study documents the test-retest reliability of a wide range of self-reported sexual health values, attitudes, knowledge and behaviours among Hispanic…

Temporal stability of the Francis Scale of Attitude toward Christianity short-form: test-retest data over one week.

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Lewis, Christopher Alan; Cruise, Sharon Mary; McGuckin, Conor

2005-04-01

This study evaluated the test-retest reliability of the Francis Scale of Attitude toward Christianity short-form. 39 Northern Irish undergraduate students completed the measure on two occasions separated by one week. Stability across the two administrations was high, r = .92, and there was no significant change between Time 1(M = 25.2, SD = 5.4) and Time 2 (M = 25.7, SD = 6.2). These data support the short-term test-retest reliability of the Francis Scale of Attitude toward Christianity short-form.

Reproducibility of graph metrics in fMRI networks

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Qawi K Telesford

2010-12-01

Full Text Available The reliability of graph metrics calculated in network analysis is essential to the interpretation of complex network organization. These graph metrics are used to deduce the small-world properties in networks. In this study, we investigated the test-retest reliability of graph metrics from functional magnetic resonance imaging (fMRI data collected for two runs in 45 healthy older adults. Graph metrics were calculated on data for both runs and compared using intraclass correlation coefficient (ICC statistics and Bland-Altman (BA plots. ICC scores describe the level of absolute agreement between two measurements and provide a measure of reproducibility. For mean graph metrics, ICC scores were high for clustering coefficient (ICC=0.86, global efficiency (ICC=0.83, path length (ICC=0.79, and local efficiency (ICC=0.75; the ICC score for degree was found to be low (ICC=0.29. ICC scores were also used to generate reproducibility maps in brain space to test voxel-wise reproducibility for unsmoothed and smoothed data. Reproducibility was uniform across the brain for global efficiency and path length, but was only high in network hubs for clustering coefficient, local efficiency and degree. BA plots were used to test the measurement repeatability of all graph metrics. All graph metrics fell within the limits for repeatability. Together, these results suggest that with exception of degree, mean graph metrics are reproducible and suitable for clinical studies. Further exploration is warranted to better understand reproducibility across the brain on a voxel-wise basis.

Interrater and test-retest reliability and validity of the Norwegian version of the BESTest and mini-BESTest in people with increased risk of falling.

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Hamre, Charlotta; Botolfsen, Pernille; Tangen, Gro Gujord; Helbostad, Jorunn L

2017-04-20

The Balance Evaluation Systems Test (BESTest) was developed to assess underlying systems for balance control in order to be able to individually tailor rehabilitation interventions to people with balance disorders. A short form, the Mini-BESTest, was developed as a screening test. The study aimed to assess interrater and test-retest reliability of the Norwegian version of the BESTest and the Mini-BESTest in community-dwelling people with increased risk of falling and to assess concurrent validity with the Fall Efficacy Scale-International (FES-I), and it was an observational study with a cross-sectional design. Forty-two persons with increased risk of falling (elderly over 65 years of age, persons with a history of stroke or Multiple Sclerosis) were assessed twice by two raters. Relative reliability was analysed with Intraclass Correlation Coefficient (ICC), and absolute reliability with standard error of measurement (SEM) and smallest detectable change (SDC). Concurrent validity was assessed against the FES-I using Spearman's rho. The BESTest showed very good interrater reliability (ICC = 0.98, SEM = 1.79, SDC 95  = 5.0) and test-retest reliability (rater A/rater B = ICC = 0.89/0.89, SEM = 3.9/4.3, SDC 95  = 10.8/11.8). The Mini-BESTest also showed very good interrater reliability (ICC = 0.95, SEM = 1.19, SDC 95  = 3.3) and test-retest reliability (rater A/rater B = ICC = 0.85/0.84, SEM = 1.8/1.9, SDC 95  = 4.9/5.2). The correlations were moderate between the FES-I and both the BESTest and the Mini-BESTest (Spearman's rho -0.51 and-0.50, p test-retest reliability when assessed in a heterogeneous sample of people with increased risk of falling. The concurrent validity measured against the FES-I showed moderate correlation. The results are comparable with earlier studies and indicate that the Norwegian versions can be used in daily clinic and in research.

Test-retest reliability of the driving habits questionnaire in older self-driving adults.

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Song, Chiang-Soon; Chun, Byung-Yoon; Chung, Hyun-Sook

2015-11-01

[Purpose] The purpose of this study was to investigate the test-retest reliability of the Driving Habits Questionnaire in community-dwelling older self-drivers. [Subjects and Methods] Seventy-four participants were recruited by convenience sampling from local rehabilitation centers. This was a cross-sectional study design that used two clinical measures: the Driving Habits Questionnaire and Mini-mental State Examination. To examine the test-retest reliability of the Driving Habits Questionnaire, the clinical tool was measured twice, five days apart. [Results] The Driving Habits Questionnaire showed good reliability for older community-dwelling self-drivers. The Cronbach's alpha coefficients for the four domains of dependence (0.572), difficulty (0.871), crashes and citations (0.689), and driving space (0.961) of the Driving Habits Questionnaire indicated good or high internal consistency. Driving difficulty correlated significantly with self-reported crashes and citations and driving space. [Conclusion] The results of this study suggest that the Driving Habits Questionnaire is a reliable measure of self-reported interview-based driving behavior in the community-dwelling elderly.

Test-Retest Reliability of Handgrip Strength as an Outcome Measure in Patients With Symptoms of Shoulder Impingement Syndrome.

Science.gov (United States)

Savva, Christos; Mougiaris, Paraskevas; Xadjimichael, Christoforos; Karagiannis, Christos; Efstathiou, Michalis

The purpose of this study was to investigate the degree of test-retest reliability of grip strength measurement using a hand dynamometer in patients with shoulder impingement syndrome. A total of 19 patients (10 women and 9 men; mean ± standard deviation age, 33.2 ± 12.9 years; range 18-59 years) with shoulder impingement syndrome were measured using a hand dynamometer by the same data collector in 2 different testing sessions with a 7-day interval. During each session, patients were encouraged to exert 3 maximal isometric contractions on the affected hand and the mean value of the 3 efforts (measured in kilogram-force [Kgf]) was used for data analysis. The intraclass correlation coefficient (ICC 2,1 ) as well as the standard error of measurement (SEM) and Bland-Altman plot were used to estimate the degree of test-retest reliability and the measurement error, respectively. Grip strength data analysis revealed an ICC 2,1 score of 0.94, which, based on the Shrout classification, is considered as excellent test-retest reliability of grip strength measurement. The small values of SEMs reported in both sessions (SEM 1 , 2.55 Kgf; SEM 2 , 2.39 Kgf) and the small width of the 95% limits of agreement in the Bland-Altman plot (ranging from -7.39 Kgf to 7.03 Kgf) reflected the measurement precision and the narrow variation of the differences during the 2 testing sessions. Results from this study identified excellent test-retest reliability of grip strength measurement in shoulder impingement syndrome, indicating its potential use as an outcome measure in clinical practice. Copyright © 2018. Published by Elsevier Inc.

Reproducibility and Reliability of the Quality of Life Questionnaire in Patients With Atrial Fibrillation

Directory of Open Access Journals (Sweden)

Rita Simone Lopes Moreira

2016-03-01

Full Text Available Abstract Background: Studies have shown the impact of atrial fibrillation (AF on the patients' quality of life. Specific questionnaires enable the evaluation of relevant events. We previously developed a questionnaire to assess the quality of life of patients with AF (AFQLQ version 1, which was reviewed in this study, and new domains were added. Objective: To demonstrate the reproducibility of the AFQLQ version 2 (AFQLQ v.2, which included the domains of fatigue, illness perception and well-being. Methods: We applied 160 questionnaires (AFQLQ v.2 and SF-36 to 40 patients, at baseline and 15 days after, to measure inter- and intraobserver reproducibility. The analysis of quality of life stability was determined by test-retest, applying the Bartko intraclass correlation coefficient (ICC. Internal consistency was assessed by Cronbach's alpha test. Results: The total score of the test-retest (n = 40 had an ICC of 0.98 in the AFQLQ v.2, and of 0.94 in the SF36. In assessing the intra- and interobserver reproducibility of the AFQLQ v.2, the ICC reliability was 0.98 and 0.97, respectively. The internal consistency had a Cronbach's alpha coefficient of 0.82, compatible with good agreement of the AFQLQ v.2. Conclusion: The AFQLQ v.2 performed better than its previous version. Similarly, the domains added contributed to make it more comprehensive and robust to assess the quality of life of patients with AF.

MicroPET imaging of 5-HT{sub 1A} receptors in rat brain: a test-retest [{sup 18}F]MPPF study

Energy Technology Data Exchange (ETDEWEB)

Aznavour, Nicolas [McGill University, Department of Psychiatry, Montreal, QC (Canada)]|[Laboratory of Neuroenergetics and Cellular Dynamics, EPFL, SV, BMI, Lausanne (Switzerland); Benkelfat, Chawki; Gravel, Paul [McGill University, Department of Psychiatry, Montreal, QC (Canada)]|[McGill University, Department of Neurology and Neurosurgery, Montreal, QC (Canada); Aliaga, Antonio [McGill University, Department of Small Animal Imaging Laboratory, Montreal, QC (Canada); Rosa-Neto, Pedro [Douglas Hospital, Molecular NeuroImaging Laboratory, Montreal, QC (Canada); Bedell, Barry [McGill University, Department of Neurology and Neurosurgery, Montreal, QC (Canada)]|[McGill University, Department of Small Animal Imaging Laboratory, Montreal, QC (Canada); Zimmer, Luc [CERMEP, ANIMAGE Department, Lyon (France)]|[Universite Lyon 1 and CNRS, Lyon (France); Descarries, Laurent [Universite de Montreal, Department of Pathology and Cell Biology, Montreal, QC (Canada)]|[Universite de Montreal, Department of Physiology, Montreal, QC (Canada)]|[Universite de Montreal, GRSNC, Montreal, QC (Canada)

2009-01-15

Earlier studies have shown that positron emission tomography (PET) imaging with the radioligand [{sup 18}F]MPPF allows for measuring the binding potential of serotonin 5-hydroxytryptamine{sub 1A} (5-HT{sub 1A}) receptors in different regions of animal and human brain, including that of 5-HT{sub 1A} autoreceptors in the raphe nuclei. In the present study, we sought to determine if such data could be obtained in rat, with a microPET (R4, Concorde Microsystems). Scans from isoflurane-anaesthetised rats (n = 18, including six test-retest) were co-registered with magnetic resonance imaging data, and binding potential, blood to plasma ratio and radiotracer efflux were estimated according to a simplified reference tissue model. Values of binding potential for hippocampus (1.2), entorhinal cortex (1.1), septum (1.1), medial prefrontal cortex (1.0), amygdala (0.8), raphe nuclei (0.6), paraventricular hypothalamic nucleus (0.5) and raphe obscurus (0.5) were comparable to those previously measured with PET in cats, non-human primates or humans. Test-retest variability was in the order of 10% in the larger brain regions (hippocampus, medial prefrontal and entorhinal cortex) and less than 20% in small nuclei such as the septum and the paraventricular hypothalamic, basolateral amygdaloid and raphe nuclei. MicroPET brain imaging of 5-HT{sub 1A} receptors with [{sup 18}F]MPPF thus represents a promising avenue for investigating 5-HT{sub 1A} receptor function in rat. (orig.)

Isokinetic Strength and Endurance Tests used Pre- and Post-Spaceflight: Test-Retest Reliability

Science.gov (United States)

Laughlin, Mitzi S.; Lee, Stuart M. C.; Loehr, James A.; Amonette, William E.

2009-01-01

To assess changes in muscular strength and endurance after microgravity exposure, NASA measures isokinetic strength and endurance across multiple sessions before and after long-duration space flight. Accurate interpretation of pre- and post-flight measures depends upon the reliability of each measure. The purpose of this study was to evaluate the test-retest reliability of the NASA International Space Station (ISS) isokinetic protocol. Twenty-four healthy subjects (12 M/12 F, 32.0 +/- 5.6 years) volunteered to participate. Isokinetic knee, ankle, and trunk flexion and extension strength as well as endurance of the knee flexors and extensors were measured using a Cybex NORM isokinetic dynamometer. The first weekly session was considered a familiarization session. Data were collected and analyzed for weeks 2-4. Repeated measures analysis of variance (alpha=0.05) was used to identify weekly differences in isokinetic measures. Test-retest reliability was evaluated by intraclass correlation coefficients (ICC) (3,1). No significant differences were found between weeks in any of the strength measures and the reliability of the strength measures were all considered excellent (ICC greater than 0.9), except for concentric ankle dorsi-flexion (ICC=0.67). Although a significant difference was noted in weekly endurance measures of knee extension (p less than 0.01), the reliability of endurance measure by week were considered excellent for knee flexion (ICC=0.97) and knee extension (ICC=0.96). Except for concentric ankle dorsi-flexion, the isokinetic strength and endurance measures are highly reliable when following the NASA ISS protocol. This protocol should allow accurate interpretation isokinetic data even with a small number of crew members.

Reproducibilidad de test de aceleración y cambio de dirección en fútbol. [Reproducibility of test acceleration and change of direction in football].

Directory of Open Access Journals (Sweden)

Julio Calleja-González

2015-04-01

Full Text Available El fútbol es un deporte multifacético en donde los factores condicionales y antropométricos son pre-requisitos necesarios para competir a alto nivel. Especialmente la velocidad y la agilidad son necesarias para alcanzar el rendimiento en fútbol. En el estudio participaron 10 jugadores (21,2 ± 2,0 años; 1,81 ± 0,1 m; 73,7 ± 5,9 kg; 22,5 ± 0,8 kg.m-2 con 3 años de experiencia en categoría regional. La reproducibilidad del test de sprint 20 metros y los test de capacidad de cambiar de dirección (MAT y test de sprint con cambios de dirección de 90ºS (90ºS fue analizada mediante el diseñó de test-retest. La reproducibilidad se calculó mediante el Coeficiente de Correlación Intraclase (CCI. La representación de la concordancia entre sesiones mediante el método de Bland y Altman. Los resultados sugieren una reproducibilidad aceptable de los test analizados. Se ha obtenido una asociación moderada entre los dos test de capacidad de cambio de dirección (MAT y 90ºS, r = 0,74. Una baja entre el sprint 20 m y el 90ºS (r = 0,46 y una baja entre el sprint 20 m y el MAT (r = 0,53. Los test de 20 m, MAT y 90ºS mostraron buenos valores de reproducibilidad absoluta y relativa. Podemos afirmar, que se ha obtenido una asociación moderada entre los test de capacidad de cambio de dirección (MAT y 90ºS. Una baja asociación entre el sprint 20 m y el MAT y una asociación baja entre el sprint 20 m y el test de 90ºS. Abstract Soccer is a many-sided sport, where the conditional and anthropometrical factors are necessary pre-requirements to compete in high level. Especially the speed and the agility, they are necessary to reach the yield in soccer. In the study 10 players took part (21,2 ± 2,0 years; 1,81 ± 0,1 m; 73,7 ± 5,9 kg; 22,5 ± 0,8 kg.m-2 with 3 years of experience in regional category. The reproducibility of the 20 meters sprint test and the test of capacity to change direction (MAT and test of sprint with way changes of 90ºS (90

Temporal Stability of Strength-Based Assessments: Test-Retest Reliability of Student and Teacher Reports

Science.gov (United States)

Romer, Natalie; Merrell, Kenneth W.

2013-01-01

This study focused on evaluating the temporal stability of self-reported and teacher-reported perceptions of students' social and emotional skills and assets. We used a test-retest reliability procedure over repeated administrations of the child, adolescent, and teacher versions of the "Social-Emotional Assets and Resilience Scales".…

Inter-rater and test-retest reliability of quality assessments by novice student raters using the Jadad and Newcastle-Ottawa Scales.

Science.gov (United States)

Oremus, Mark; Oremus, Carolina; Hall, Geoffrey B C; McKinnon, Margaret C

2012-01-01

Quality assessment of included studies is an important component of systematic reviews. The authors investigated inter-rater and test-retest reliability for quality assessments conducted by inexperienced student raters. Student raters received a training session on quality assessment using the Jadad Scale for randomised controlled trials and the Newcastle-Ottawa Scale (NOS) for observational studies. Raters were randomly assigned into five pairs and they each independently rated the quality of 13-20 articles. These articles were drawn from a pool of 78 papers examining cognitive impairment following electroconvulsive therapy to treat major depressive disorder. The articles were randomly distributed to the raters. Two months later, each rater re-assessed the quality of half of their assigned articles. McMaster Integrative Neuroscience Discovery and Study Program. 10 students taking McMaster Integrative Neuroscience Discovery and Study Program courses. The authors measured inter-rater reliability using κ and the intraclass correlation coefficient type 2,1 or ICC(2,1). The authors measured test-retest reliability using ICC(2,1). Inter-rater reliability varied by scale question. For the six-item Jadad Scale, question-specific κs ranged from 0.13 (95% CI -0.11 to 0.37) to 0.56 (95% CI 0.29 to 0.83). The ranges were -0.14 (95% CI -0.28 to 0.00) to 0.39 (95% CI -0.02 to 0.81) for the NOS cohort and -0.20 (95% CI -0.49 to 0.09) to 1.00 (95% CI 1.00 to 1.00) for the NOS case-control. For overall scores on the six-item Jadad Scale, ICC(2,1)s for inter-rater and test-retest reliability (accounting for systematic differences between raters) were 0.32 (95% CI 0.08 to 0.52) and 0.55 (95% CI 0.41 to 0.67), respectively. Corresponding ICC(2,1)s for the NOS cohort were -0.19 (95% CI -0.67 to 0.35) and 0.62 (95% CI 0.25 to 0.83), and for the NOS case-control, the ICC(2,1)s were 0.46 (95% CI -0.13 to 0.92) and 0.83 (95% CI 0.48 to 0.95). Inter-rater reliability was generally poor

Can radiomics features be reproducibly measured from CBCT images for patients with non-small cell lung cancer?

Energy Technology Data Exchange (ETDEWEB)

Fave, Xenia, E-mail: xjfave@mdanderson.org; Fried, David [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 and The University of Texas Graduate School of Biomedical Sciences at Houston, 6767 Bertner Avenue, Houston, Texas 77030 (United States); Mackin, Dennis; Yang, Jinzhong; Zhang, Joy; Balter, Peter; Followill, David [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Gomez, Daniel [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Kyle Jones, A. [Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Stingo, Francesco [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Fontenot, Jonas [Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809 (United States); Court, Laurence [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 and Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States)

2015-12-15

Purpose: Increasing evidence suggests radiomics features extracted from computed tomography (CT) images may be useful in prognostic models for patients with nonsmall cell lung cancer (NSCLC). This study was designed to determine whether such features can be reproducibly obtained from cone-beam CT (CBCT) images taken using medical Linac onboard-imaging systems in order to track them through treatment. Methods: Test-retest CBCT images of ten patients previously enrolled in a clinical trial were retrospectively obtained and used to determine the concordance correlation coefficient (CCC) for 68 different texture features. The volume dependence of each feature was also measured using the Spearman rank correlation coefficient. Features with a high reproducibility (CCC > 0.9) that were not due to volume dependence in the patient test-retest set were further examined for their sensitivity to differences in imaging protocol, level of scatter, and amount of motion by using two phantoms. The first phantom was a texture phantom composed of rectangular cartridges to represent different textures. Features were measured from two cartridges, shredded rubber and dense cork, in this study. The texture phantom was scanned with 19 different CBCT imagers to establish the features’ interscanner variability. The effect of scatter on these features was studied by surrounding the same texture phantom with scattering material (rice and solid water). The effect of respiratory motion on these features was studied using a dynamic-motion thoracic phantom and a specially designed tumor texture insert of the shredded rubber material. The differences between scans acquired with different Linacs and protocols, varying amounts of scatter, and with different levels of motion were compared to the mean intrapatient difference from the test-retest image set. Results: Of the original 68 features, 37 had a CCC >0.9 that was not due to volume dependence. When the Linac manufacturer and imaging protocol

Influences on the Test-Retest Reliability of Functional Connectivity MRI and its Relationship with Behavioral Utility.

Science.gov (United States)

Noble, Stephanie; Spann, Marisa N; Tokoglu, Fuyuze; Shen, Xilin; Constable, R Todd; Scheinost, Dustin

2017-11-01

Best practices are currently being developed for the acquisition and processing of resting-state magnetic resonance imaging data used to estimate brain functional organization-or "functional connectivity." Standards have been proposed based on test-retest reliability, but open questions remain. These include how amount of data per subject influences whole-brain reliability, the influence of increasing runs versus sessions, the spatial distribution of reliability, the reliability of multivariate methods, and, crucially, how reliability maps onto prediction of behavior. We collected a dataset of 12 extensively sampled individuals (144 min data each across 2 identically configured scanners) to assess test-retest reliability of whole-brain connectivity within the generalizability theory framework. We used Human Connectome Project data to replicate these analyses and relate reliability to behavioral prediction. Overall, the historical 5-min scan produced poor reliability averaged across connections. Increasing the number of sessions was more beneficial than increasing runs. Reliability was lowest for subcortical connections and highest for within-network cortical connections. Multivariate reliability was greater than univariate. Finally, reliability could not be used to improve prediction; these findings are among the first to underscore this distinction for functional connectivity. A comprehensive understanding of test-retest reliability, including its limitations, supports the development of best practices in the field. © The Author 2017. Published by Oxford University Press.

Reproducibility for Heart Rate Variability Analysis during 6-Min Walk Test in Patients with Heart Failure and Agreement between Devices.

Science.gov (United States)

Braga, Lays Magalhães; Prado, Gustavo Faibischew; Umeda, Iracema Ioco Kikuchi; Kawauchi, Tatiana Satie; Taboada, Adriana Marques Fróes; Azevedo, Raymundo Soares; Pereira Filho, Horacio Gomes; Grupi, César José; Souza, Hayala Cristina Cavenague; Moreira, Dalmo Antônio Ribeiro; Nakagawa, Naomi Kondo

2016-01-01

Heart rate variability (HRV) analysis is a useful method to assess abnormal functioning in the autonomic nervous system and to predict cardiac events in patients with heart failure (HF). HRV measurements with heart rate monitors have been validated with an electrocardiograph in healthy subjects but not in patients with HF. We explored the reproducibility of HRV in two consecutive six-minute walk tests (6MW), 60-minute apart, using a heart rate monitor (PolarS810i) and a portable electrocardiograph (called Holter) in 50 HF patients (mean age 59 years, NYHA II, left ventricular ejection fraction ~35%). The reproducibility for each device was analysed using a paired t-test or the Wilcoxon signed-rank test. Additionally, we assessed the agreement between the two devices based on the HRV indices at rest, during the 6MW and during recovery using concordance correlation coefficients (CCC), 95% confidence intervals and Bland-Altman plots. The test-retest for the HRV analyses was reproducible using Holter and PolarS810i at rest but not during recovery. In the second 6MW, patients showed significant increases in rMSSD and walking distance. The PolarS810i measurements had remarkably high concordance correlation [0.86reproducibility of HRV at rest in two consecutive 6MW using Holter and PolarS810i. Additionally, PolarS810i produced good agreements in short-term HRV indices based on Holter simultaneous recordings at rest, during the 6MW and recovery in HF patients.

Hip abduction-adduction strength and one-leg hop tests: test-retest reliability and relationship to function in elite ice hockey players.

Science.gov (United States)

Kea, J; Kramer, J; Forwell, L; Birmingham, T

2001-08-01

Single group, test-retest. To determine: (1) hip abduction and adduction torques during concentric and eccentric muscle actions, (2) medial and lateral one-leg hop distances, (3) the test-retest reliability of these measurements, and (4) the relationship between isokinetic measures of hip muscle strength and hop distances in elite ice hockey players. The skating motion used in ice hockey requires strong contractions of the hip and knee musculature. However, baseline scores for hip strength and hop distances, their test-retest reliability, and measures of the extent to which these tests are related for this population are not available. The dominant leg of 27 men (mean age 20 +/- 3 yrs) was tested on 2 occasions. Hip abduction and adduction movements were completed at 60 degrees.s(-1) angular velocity, with the subject lying on the non-test side and the test leg moving vertically in the subject's coronal plane. One-leg hops requiring jumping from and landing on the same leg without losing balance were completed in the medial and lateral directions. Hip adduction torques were significantly greater than abduction torques during both concentric and eccentric muscle actions, while no significant difference was observed between medial and lateral hop distances. Although hop test scores produced excellent ICCs (> 0.75) when determined using scores on 1 occasion, torques needed to be averaged over 2 test occasions to reach this level. Correlations between the strength and hop tests ranged from slight to low (r = -0.26 to 0.27) and were characterized by wide 95% confidence intervals (-0.54 to 0.61). Isokinetic tests of hip abduction and adduction did not provide a strong indication of performance during sideways hop tests. Although isokinetic tests can provide a measure of muscular strength under specific test conditions, they should not be relied upon as a primary indicator of functional abilities or readiness to return to activity.

Establishing survey validity and reliability for American Indians through "think aloud" and test-retest methods.

Science.gov (United States)

Hauge, Cindy Horst; Jacobs-Knight, Jacque; Jensen, Jamie L; Burgess, Katherine M; Puumala, Susan E; Wilton, Georgiana; Hanson, Jessica D

2015-06-01

The purpose of this study was to use a mixed-methods approach to determine the validity and reliability of measurements used within an alcohol-exposed pregnancy prevention program for American Indian women. To develop validity, content experts provided input into the survey measures, and a "think aloud" methodology was conducted with 23 American Indian women. After revising the measurements based on this input, a test-retest was conducted with 79 American Indian women who were randomized to complete either the original measurements or the new, modified measurements. The test-retest revealed that some of the questions performed better for the modified version, whereas others appeared to be more reliable for the original version. The mixed-methods approach was a useful methodology for gathering feedback on survey measurements from American Indian participants and in indicating specific survey questions that needed to be modified for this population. © The Author(s) 2015.

Laterality judgments in people with low back pain--A cross-sectional observational and test-retest reliability study.

Science.gov (United States)

Linder, Martin; Michaelson, Peter; Röijezon, Ulrik

2016-02-01

Disruption of cortical representation, or body schema, has been indicated as a factor in the persistence and recurrence of low back pain (LBP). This has been observed through impaired laterality judgment ability and it has been suggested that this ability is affected in a spatial rather than anatomical manner. We compared laterality judgment performance of foot and trunk movements between people with LBP with or without leg pain and healthy controls, and investigated associations between test performance and pain. We also assessed the test-retest reliability of the Recognise Online™ software when used in a clinical and a home setting. Cross-sectional observational and test-retest study. Thirty individuals with LBP and 30 healthy controls performed judgment tests of foot and trunk laterality once supervised in a clinic and twice at home. No statistically significant group differences were found. LBP intensity was negatively related to trunk laterality accuracy (p = 0.019). Intraclass correlation values ranged from 0.51 to 0.91. Reaction time improved significantly between test occasions while accuracy did not. Laterality judgments were not impaired in subjects with LBP compared to controls. Further research may clarify the relationship between pain mechanisms in LBP and laterality judgment ability. Reliability values were mostly acceptable, with wide and low confidence intervals, suggesting test-retest reliability for Recognise Online™ could be questioned in this trial. A significant learning effect was observed which should be considered in clinical and research application of the test. Copyright © 2015 Elsevier Ltd. All rights reserved.

Test-retest reliability and four-week changes in cardiopulmonary fitness in stroke patients: evaluation using a robotics-assisted tilt table.

Science.gov (United States)

Saengsuwan, Jittima; Berger, Lucia; Schuster-Amft, Corina; Nef, Tobias; Hunt, Kenneth J

2016-09-06

Exercise testing devices for evaluating cardiopulmonary fitness in patients with severe disability after stroke are lacking, but we have adapted a robotics-assisted tilt table (RATT) for cardiopulmonary exercise testing (CPET). Using the RATT in a sample of patients after stroke, this study aimed to investigate test-retest reliability and repeatability of CPET and to prospectively investigate changes in cardiopulmonary outcomes over a period of four weeks. Stroke patients with all degrees of disability underwent 3 separate CPET sessions: 2 tests at baseline (TB1 and TB2) and 1 test at follow up (TF). TB1 and TB2 were at least 24 h apart. TB2 and TF were 4 weeks apart. A RATT equipped with force sensors in the thigh cuffs, a work rate estimation algorithm and a real-time visual feedback system was used to guide the patients' exercise work rate during CPET. Test-retest reliability and repeatability of CPET variables were analysed using paired t-tests, the intraclass correlation coefficient (ICC), the coefficient of variation (CoV), and Bland and Altman limits of agreement. Changes in cardiopulmonary fitness during four weeks were analysed using paired t-tests. Seventeen sub-acute and chronic stroke patients (age 62.7 ± 10.4 years [mean ± SD]; 8 females) completed the test sessions. The median time post stroke was 350 days. There were 4 severely disabled, 1 moderately disabled and 12 mildly disabled patients. For test-retest, there were no statistically significant differences between TB1 and TB2 for most CPET variables. Peak oxygen uptake, peak heart rate, peak work rate and oxygen uptake at the ventilatory anaerobic threshold (VAT) and respiratory compensation point (RCP) showed good to excellent test-retest reliability (ICC 0.65-0.94). For all CPET variables, CoV was 4.1-14.5 %. The mean difference was close to zero in most of the CPET variables. There were no significant changes in most cardiopulmonary performance parameters during the 4-week period

Reproducibility of ultrasonic testing

International Nuclear Information System (INIS)

Lecomte, J.-C.; Thomas, Andre; Launay, J.-P.; Martin, Pierre

The reproducibility of amplitude quotations for both artificial and natural reflectors was studied for several combinations of instrument/search unit, all being of the same type. This study shows that in industrial inspection if a range of standardized equipment is used, a margin of error of about 6 decibels has to be taken into account (confidence interval of 95%). This margin is about 4 to 5 dB for natural or artificial defects located in the central area and about 6 to 7 dB for artificial defects located on the back surface. This lack of reproducibility seems to be attributable first to the search unit and then to the instrument and operator. These results were confirmed by analysis of calibration data obtained from 250 tests performed by 25 operators under shop conditions. The margin of error was higher than the 6 dB obtained in the study [fr

Fully automated synthesis of 11C-acetate as tumor PET tracer by simple modified solid-phase extraction purification

International Nuclear Information System (INIS)

Tang, Xiaolan; Tang, Ganghua; Nie, Dahong

2013-01-01

Introduction: Automated synthesis of 11 C-acetate ( 11 C-AC) as the most commonly used radioactive fatty acid tracer is performed by a simple, rapid, and modified solid-phase extraction (SPE) purification. Methods: Automated synthesis of 11 C-AC was implemented by carboxylation reaction of MeMgBr on a polyethylene Teflon loop ring with 11 C-CO 2 , followed by acidic hydrolysis with acid and SCX cartridge, and purification on SCX, AG11A8 and C18 SPE cartridges using a commercially available 11 C-tracer synthesizer. Quality control test and animals positron emission tomography (PET) imaging were also carried out. Results: A high and reproducible decay-uncorrected radiochemical yield of (41.0±4.6)% (n=10) was obtained from 11 C-CO 2 within the whole synthesis time about 8 min. The radiochemical purity of 11 C-AC was over 95% by high-performance liquid chromatography (HPLC) analysis. Quality control test and PET imaging showed that 11 C-AC injection produced by the simple SPE procedure was safe and efficient, and was in agreement with the current Chinese radiopharmaceutical quality control guidelines. Conclusion: The novel, simple, and rapid method is readily adapted to the fully automated synthesis of 11 C-AC on several existing commercial synthesis module. The method can be used routinely to produce 11 C-AC for preclinical and clinical studies with PET imaging. - Highlights: • A fully automated synthesis of 11 C-acetate by simple modified solid-phase extraction purification has been developed. • Typical non-decay-corrected yields were (41.0±4.6)% (n=10) • Radiochemical purity was determined by radio-HPLC analysis on a C18 column using the gradient program, instead of expensive organic acid column or anion column. • QC testing (RCP>99%)

Caffeine-11C, ephedrine-11C and methylephedrine-11C: synthesis and distribution in mice

International Nuclear Information System (INIS)

Saji, Hideo; Ido, Tatsuo; Iwata, Ren; Suzuki, Kazutoshi; Tamate, Kazuhiko

1978-01-01

Caffeine, ephedrine and methylephedrine were labeled with carbon-11 by the action of methyliodide- 11 C on theophylline, norephedrine and ephedrine, respectively. Caffeine- 11 C was prepared in 44 min. with a radiochemical yield of 40%, ephedrine- 11 C in 45 min. with a 11% radiochemical yield and methylephedrine- 11 C in 36 min. with a 43% radiochemical yield. When injected in mice intravenously, these products show a high uptake in the liver, the kidney and the blood for caffeine- 11 C and in the liver and the kidney for ephedrine- 11 C and methylephedrine- 11 C. The brain uptake for these products was found to be 2.4 to 3.9% of the injected dose per gram at 5 min. after injection. These studies in mice have demonstrated that these products are potentially useful agents for the dynamic studies of the brain. (auth.)

Test-retest reliability and task order effects of emotional cognitive tests in healthy subjects.

Science.gov (United States)

Adams, Thomas; Pounder, Zoe; Preston, Sally; Hanson, Andy; Gallagher, Peter; Harmer, Catherine J; McAllister-Williams, R Hamish

2016-11-01

Little is known of the retest reliability of emotional cognitive tasks or the impact of using different tasks employing similar emotional stimuli within a battery. We investigated this in healthy subjects. We found improved overall performance in an emotional attentional blink task (EABT) with repeat testing at one hour and one week compared to baseline, but the impact of an emotional stimulus on performance was unchanged. Similarly, performance on a facial expression recognition task (FERT) was better one week after a baseline test, though the relative effect of specific emotions was unaltered. There was no effect of repeat testing on an emotional word categorising, recall and recognition task. We found no difference in performance in the FERT and EABT irrespective of task order. We concluded that it is possible to use emotional cognitive tasks in longitudinal studies and combine tasks using emotional facial stimuli in a single battery.

Forward lunge as a functional performance test in ACL deficient subjects: test-retest reliability

DEFF Research Database (Denmark)

Alkjaer, Tine; Henriksen, Marius; Dyhre-Poulsen, Poul

2009-01-01

The forward lunge movement may be used as a functional performance test of anterior cruciate ligament (ACL) deficient and reconstructed subjects. The purposes were 1) to determine the test-retest reliability of a forward lunge in healthy subjects and 2) to determine the required numbers...... of repetitions necessary to yield satisfactory reliability. Nineteen healthy subjects performed four trials of a forward lunge on two different days. The movement time, impulses of the ground reaction forces (IFz, IFy), knee joint kinematics and dynamics during the forward lunge were calculated. The relative...... reliability was determined by calculation of Intraclass Correlation Coefficients (ICC). The IFz, IFy and the positive work of the knee extensors showed excellent reliability (ICC >0.75). All other variables demonstrated acceptable reliability (0.4>ICCreliability increased when more than...

Test-retest reliability and construct validity of the ENERGY-child questionnaire on energy balance-related behaviours and their potential determinants: the ENERGY-project

Directory of Open Access Journals (Sweden)

Singh Amika S

2011-12-01

Full Text Available Abstract Background Insight in children's energy balance-related behaviours (EBRBs and their determinants is important to inform obesity prevention research. Therefore, reliable and valid tools to measure these variables in large-scale population research are needed. Objective To examine the test-retest reliability and construct validity of the child questionnaire used in the ENERGY-project, measuring EBRBs and their potential determinants among 10-12 year old children. Methods We collected data among 10-12 year old children (n = 730 in the test-retest reliability study; n = 96 in the construct validity study in six European countries, i.e. Belgium, Greece, Hungary, the Netherlands, Norway, and Spain. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC and percentage agreement comparing scores from two measurements, administered one week apart. To assess construct validity, the agreement between questionnaire responses and a subsequent face-to-face interview was assessed using ICC and percentage agreement. Results Of the 150 questionnaire items, 115 (77% showed good to excellent test-retest reliability as indicated by ICCs > .60 or percentage agreement ≥ 75%. Test-retest reliability was moderate for 34 items (23% and poor for one item. Construct validity appeared to be good to excellent for 70 (47% of the 150 items, as indicated by ICCs > .60 or percentage agreement ≥ 75%. From the other 80 items, construct validity was moderate for 39 (26% and poor for 41 items (27%. Conclusions Our results demonstrate that the ENERGY-child questionnaire, assessing EBRBs of the child as well as personal, family, and school-environmental determinants related to these EBRBs, has good test-retest reliability and moderate to good construct validity for the large majority of items.

Test-retest reliability and construct validity of the ENERGY-child questionnaire on energy balance-related behaviours and their potential determinants: the ENERGY-project

Science.gov (United States)

2011-01-01

Background Insight in children's energy balance-related behaviours (EBRBs) and their determinants is important to inform obesity prevention research. Therefore, reliable and valid tools to measure these variables in large-scale population research are needed. Objective To examine the test-retest reliability and construct validity of the child questionnaire used in the ENERGY-project, measuring EBRBs and their potential determinants among 10-12 year old children. Methods We collected data among 10-12 year old children (n = 730 in the test-retest reliability study; n = 96 in the construct validity study) in six European countries, i.e. Belgium, Greece, Hungary, the Netherlands, Norway, and Spain. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC) and percentage agreement comparing scores from two measurements, administered one week apart. To assess construct validity, the agreement between questionnaire responses and a subsequent face-to-face interview was assessed using ICC and percentage agreement. Results Of the 150 questionnaire items, 115 (77%) showed good to excellent test-retest reliability as indicated by ICCs > .60 or percentage agreement ≥ 75%. Test-retest reliability was moderate for 34 items (23%) and poor for one item. Construct validity appeared to be good to excellent for 70 (47%) of the 150 items, as indicated by ICCs > .60 or percentage agreement ≥ 75%. From the other 80 items, construct validity was moderate for 39 (26%) and poor for 41 items (27%). Conclusions Our results demonstrate that the ENERGY-child questionnaire, assessing EBRBs of the child as well as personal, family, and school-environmental determinants related to these EBRBs, has good test-retest reliability and moderate to good construct validity for the large majority of items. PMID:22152048

A simple, versatile, low-cost and remotely operated apparatus for [11C]acetate, [11C]choline, [11C]methionine and [11C]PIB synthesis

International Nuclear Information System (INIS)

Cheung Manki; Ho Chilai

2009-01-01

A simple, efficient and remotely operated synthesis apparatus for carrying out routine [ 11 C]carboxylation, on-column and bubbling [ 11 C]methylation was essential for reliable, day-to-day production of [ 11 C]-labelled PET radiopharmaceuticals. We developed an in-house apparatus specifically applied to the synthesis of [ 11 C]acetate, [ 11 C]choline, [ 11 C]methionine and 2-(4'-N-[ 11 C]methylaminophenyl)-6-hydroxybenzothiazole ([ 11 C]PIB), where high radiochemical purity (≥97%) and moderate radiochemical yields (18% for [ 11 C]PIB, 41-55% for the others) could be achieved. These findings provided evidence that this was a fast, versatile and reliable apparatus suitable for a PET/CT centre with limited financial budget and hot cell space for synthesis of [ 11 C]-labelled radiopharmaceuticals

Test-retest reliability of the 40 Hz EEG auditory steady-state response.

Directory of Open Access Journals (Sweden)

Kristina L McFadden

Full Text Available Auditory evoked steady-state responses are increasingly being used as a marker of brain function and dysfunction in various neuropsychiatric disorders, but research investigating the test-retest reliability of this response is lacking. The purpose of this study was to assess the consistency of the auditory steady-state response (ASSR across sessions. Furthermore, the current study aimed to investigate how the reliability of the ASSR is impacted by stimulus parameters and analysis method employed. The consistency of this response across two sessions spaced approximately 1 week apart was measured in nineteen healthy adults using electroencephalography (EEG. The ASSR was entrained by both 40 Hz amplitude-modulated white noise and click train stimuli. Correlations between sessions were assessed with two separate analytical techniques: a channel-level analysis across the whole-head array and b signal-space projection from auditory dipoles. Overall, the ASSR was significantly correlated between sessions 1 and 2 (p<0.05, multiple comparison corrected, suggesting adequate test-retest reliability of this response. The current study also suggests that measures of inter-trial phase coherence may be more reliable between sessions than measures of evoked power. Results were similar between the two analysis methods, but reliability varied depending on the presented stimulus, with click train stimuli producing more consistent responses than white noise stimuli.

Test-retest and between-site reliability in a multicenter fMRI study.

Science.gov (United States)

Friedman, Lee; Stern, Hal; Brown, Gregory G; Mathalon, Daniel H; Turner, Jessica; Glover, Gary H; Gollub, Randy L; Lauriello, John; Lim, Kelvin O; Cannon, Tyrone; Greve, Douglas N; Bockholt, Henry Jeremy; Belger, Aysenil; Mueller, Bryon; Doty, Michael J; He, Jianchun; Wells, William; Smyth, Padhraic; Pieper, Steve; Kim, Seyoung; Kubicki, Marek; Vangel, Mark; Potkin, Steven G

2008-08-01

In the present report, estimates of test-retest and between-site reliability of fMRI assessments were produced in the context of a multicenter fMRI reliability study (FBIRN Phase 1, www.nbirn.net). Five subjects were scanned on 10 MRI scanners on two occasions. The fMRI task was a simple block design sensorimotor task. The impulse response functions to the stimulation block were derived using an FIR-deconvolution analysis with FMRISTAT. Six functionally-derived ROIs covering the visual, auditory and motor cortices, created from a prior analysis, were used. Two dependent variables were compared: percent signal change and contrast-to-noise-ratio. Reliability was assessed with intraclass correlation coefficients derived from a variance components analysis. Test-retest reliability was high, but initially, between-site reliability was low, indicating a strong contribution from site and site-by-subject variance. However, a number of factors that can markedly improve between-site reliability were uncovered, including increasing the size of the ROIs, adjusting for smoothness differences, and inclusion of additional runs. By employing multiple steps, between-site reliability for 3T scanners was increased by 123%. Dropping one site at a time and assessing reliability can be a useful method of assessing the sensitivity of the results to particular sites. These findings should provide guidance toothers on the best practices for future multicenter studies.

Test-retest reliability of the proposed DSM-5 eating disorder diagnostic criteria

Science.gov (United States)

Sysko, Robyn; Roberto, Christina A.; Barnes, Rachel D.; Grilo, Carlos M.; Attia, Evelyn; Walsh, B. Timothy

2012-01-01

The proposed DSM-5 classification scheme for eating disorders includes both major and minor changes to the existing DSM-IV diagnostic criteria. It is not known what effect these modifications will have on the ability to make reliable diagnoses. Two studies were conducted to evaluate the short-term test-retest reliability of the proposed DSM-5 eating disorder diagnoses: anorexia nervosa, bulimia nervosa, binge eating disorder, and feeding and eating conditions not elsewhere classified. Participants completed two independent telephone interviews with research assessors (n=70 Study 1; n=55 Study 2). Fair to substantial agreements (κ= 0.80 and 0.54) were observed across eating disorder diagnoses in Study 1 and Study 2, respectively. Acceptable rates of agreement were identified for the individual eating disorder diagnoses, including DSM-5 anorexia nervosa (κ’s of 0.81 to 0.97), bulimia nervosa (κ=0.84), binge eating disorder (κ’s of 0.75 and 0.61), and feeding and eating disorders not elsewhere classified (κ’s of 0.70 and 0.46). Further, improved short-term test-retest reliability was noted when using the DSM-5, in comparison to DSM-IV, criteria for binge eating disorder. Thus, these studies found that trained interviewers can reliably diagnose eating disorders using the proposed DSM-5 criteria; however, additional data from general practice settings and community samples are needed. PMID:22401974

Binding kinetics of 11C-N-methyl piperidyl benzilate (11C-NMPB) in a rhesus monkey brain using the cerebellum as a reference region

International Nuclear Information System (INIS)

Itoh, Takashi; Tanaka, Masayasu; Suzuki, Kasutoshi; Kobayashi, Kaoru; Inoue, Osamu

2005-01-01

The binding kinetics of' 11 C-N-methyl piperidyl benzilate ( 11 C-NMPB) in rhesus monkey brain were studied using animal positron emission tomography (PET) (SHR2000). This study is intended to assess the validity of the method using the cerebellum as a reference region, and to evaluate the effects of anesthesia on 11 C -NMPB binding. Two monkeys, anesthetized with ketamine, received intravenous 11 C-NMPB alone (370-760 MBq, 11 C-NMPB accumulated densely in the striatum and cerebral cortex with time. In contrast, the tracer accumulation significantly decreased with increased doses of nonradioactive NMPB. In the cerebellum, on the other hand, the accumulation of 11 C-NMPB remained low and the tracer was slowly eliminated from the brain following the injection. 11 C-NMPB binding in the cerebellum was barely affected by the increased dose of nonradioactive NMPB. We thus concluded that the specific 11 C-NMPB binding was negligible in the cerebellum, and performed simplified evaluation of 11 C-NMPB binding in each brain region by a graphical method using the cerebellum as a reference region. PET was conducted 26 times, in total both in ketamine-anesthetized and awake monkeys (n=3 each). Measurements of 11 C-NMPB binding showed good run-to-run reproducibility within individual animals. When 11 C-NMPB binding was compared between ketamine-treated and awake animals, a significant increase in 11 C-NMPB binding was observed in the striatum but not in other brain regions of ketamine-treated animals. (author)

CPM Test-Retest Reliability: "Standard" vs "Single Test-Stimulus" Protocols.

Science.gov (United States)

Granovsky, Yelena; Miller-Barmak, Adi; Goldstein, Oren; Sprecher, Elliot; Yarnitsky, David

2016-03-01

Assessment of pain inhibitory mechanisms using conditioned pain modulation (CPM) is relevant clinically in prediction of pain and analgesic efficacy. Our objective is to provide necessary estimates of intersession CPM reliability, to enable transformation of the CPM paradigm into a clinical tool. Two cohorts of young healthy subjects (N = 65) participated in two dual-session studies. In Study I, a Bath-Thermode CPM protocol was used, with hot water immersion and contact heat as conditioning- and test-stimuli, respectively, in a classical parallel CPM design introducing test-stimulus first, and then the conditioning- and repeated test-stimuli in parallel. Study II consisted of two CPM protocols: 1) Two-Thermodes, one for each of the stimuli, in the same parallel design as above, and 2) single test-stimulus (STS) protocol with a single administration of a contact heat test-stimulus, partially overlapped in time by a remote shorter contact heat as conditioning stimulus. Test-retest reliability was assessed within 3-7 days. The STS-CPM had superior reliability intraclass correlation (ICC 2 ,: 1  = 0.59) over Bath-Thermode (ICC 2 ,: 1  = 0.34) or Two-Thermodes (ICC 2 ,: 1  = 0.21) protocols. The hand immersion conditioning pain had higher reliability than thermode pain (ICC 2 ,: 1  = 0.76 vs ICC 2 ,: 1  = 0.16). Conditioned test-stimulus pain scores were of good (ICC 2 ,: 1  = 0.62) or fair (ICC 2 ,: 1  = 0.43) reliability for the Bath-Thermode and the STS, respectively, but not for the Two-Thermodes protocol (ICC 2 ,: 1  = 0.20). The newly developed STS-CPM paradigm was more reliable than other CPM protocols tested here, and should be further investigated for its clinical relevance. It appears that large contact size of the conditioning-stimulus and use of single rather than dual test-stimulus pain contribute to augmentation of CPM reliability. © 2015 American Academy of Pain Medicine. All rights reserved. For permissions, please e

Test-retest reliability of trunk motor variability measured by large-array surface electromyography.

Science.gov (United States)

Abboud, Jacques; Nougarou, François; Loranger, Michel; Descarreaux, Martin

2015-01-01

The objective of this study was to evaluate the test-retest reliability of the trunk muscle activity distribution in asymptomatic participants during muscle fatigue using large-array surface electromyography (EMG). Trunk muscle activity distribution was evaluated twice, with 3 to 4 days between them, in 27 asymptomatic volunteers using large-array surface EMG. Motor variability, assessed with 2 different variables (the centroid coordinates of the root mean square map and the dispersion variable), was evaluated during a low back muscle fatigue task. Test-retest reliability of muscle activity distribution was obtained using Pearson correlation coefficients. A shift in the distribution of EMG amplitude toward the lateral-caudal region of the lumbar erector spinae induced by muscle fatigue was observed. Moderate to very strong correlations were found between both sessions in the last 3 phases of the fatigue task for both motor variability variables, whereas weak to moderate correlations were found in the first phases of the fatigue task only for the dispersion variable. These findings show that, in asymptomatic participants, patterns of EMG activity are less reliable in initial stages of muscle fatigue, whereas later stages are characterized by highly reliable patterns of EMG activity. Copyright © 2015 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.

Assessment of lower urinary tract symptoms in women by a self-administered questionnaire: test-retest reliability

DEFF Research Database (Denmark)

Bernstein, Inge Thomsen; Sejr, T; Able, I

1996-01-01

A self-administered questionnaire assessing female lower urinary tract symptoms and their impact on quality of life is described and validated, on 56 females in six participating departments. The patients answered two identical questionnaires on separate occasions before treatment. Test-retest re...

A Test-Retest Analysis of the Vanderbilt Assessment for Leadership in Education in the USA

Science.gov (United States)

Minor, Elizabeth Covay; Porter, Andrew C.; Murphy, Joseph; Goldring, Ellen; Elliott, Stephen N.

2017-01-01

The Vanderbilt Assessment for Leadership in Education (VAL-ED) is a 360-degree learning-centered behaviors principal evaluation tool that includes ratings from the principal, supervisors, and teachers. The current study assesses the test-retest reliability of the VAL-ED for a sample of seven school districts as part of multiple validity and…

The Test-Retest Reliability of New Generation Power Indices of Wingate All-Out Test

Directory of Open Access Journals (Sweden)

Ozgur Ozkaya

2018-04-01

Full Text Available Although reliability correlations of traditional power indices of the Wingate test have been well documented, no study has analyzed new generation power indices based on milliseconds obtained from a Peak Bike. The purpose of this study was to investigate the retest reliability of new generation power indices. Thirty-two well-trained male athletes who were specialized in basketball, football, tennis, or track and field volunteered to take part in the study (age: 24.3 ± 2.2 years; body mass: 77 ± 8.3 kg; height: 180.3 ± 6.3 cm. Participants performed two Wingate all-out sessions on two separate days. Intra-class correlation coefficient (ICC, standard error measurement (SEM, smallest real differences (SRD and coefficient of variation (CV scores were analyzed based on the test and retest data. Reliability results of traditional power indices calculated based on 5-s means such as peak power, average power, power drop, and fatigue index ratio were similar with the previous findings in literature (ICC ≥ 0.94; CV ≤ 2.8%; SEM ≤ 12.28; SRD% ≤ 7.7%. New generation power indices such as peak power, average power, lowest power, power drop, fatigue index, power decline, maximum speed as rpm, and amount of total energy expenditure demonstrated high reliability (ICC ≥ 0.94; CV ≤ 4.3%; SEM ≤ 10.36; SRD% ≤ 8.8%. Time to peak power, time at maximum speed, and power at maximum speed showed a moderate level of reliability (ICC ≥ 0.73; CV ≤ 8.9%; SEM ≤ 63.01; SRD% ≤ 22.4%. The results of this study indicate that reliability correlations and SRD% of new generation power and fatigue-related indices are similar with traditional 5-s means. However, new time-related indices are very sensitive and moderately reliable.

Test-retest reliability of stride time variability while dual tasking in healthy and demented adults with frontotemporal degeneration

Directory of Open Access Journals (Sweden)

Herrmann Francois R

2011-07-01

Full Text Available Abstract Background Although test-retest reliability of mean values of spatio-temporal gait parameters has been assessed for reliability while walking alone (i.e., single tasking, little is known about the test-retest reliability of stride time variability (STV while performing an attention demanding-task (i.e., dual tasking. The objective of this study was to examine immediate test-retest reliability of STV while single and dual tasking in cognitively healthy older individuals (CHI and in demented patients with frontotemporal degeneration (FTD. Methods Based on a cross-sectional design, 69 community-dwelling CHI (mean age 75.5 ± 4.3; 43.5% women and 14 demented patients with FTD (mean age 65.7 ± 9.8 years; 6.7% women walked alone (without performing an additional task; i.e., single tasking and while counting backward (CB aloud starting from 50 (i.e., dual tasking. Each subject completed two trials for all the testing conditions. The mean value and the coefficient of variation (CoV of stride time while walking alone and while CB at self-selected walking speed were measured using GAITRite® and SMTEC® footswitch systems. Results ICC of mean value in CHI under both walking conditions were higher than ICC of demented patients with FTD and indicated perfect reliability (ICC > 0.80. Reliability of mean value was better while single tasking than dual tasking in CHI (ICC = 0.96 under single-task and ICC = 0.86 under dual-task, whereas it was the opposite in demented patients (ICC = 0.65 under single-task and ICC = 0.81 under dual-task. ICC of CoV was slight to poor whatever the group of participants and the walking condition (ICC Conclusions The immediate test-retest reliability of the mean value of stride time in single and dual tasking was good in older CHI as well as in demented patients with FTD. In contrast, the variability of stride time was low in both groups of participants.

Temporal stability of preferences and willingness to pay for natural areas in choice experiments: A test-retest

NARCIS (Netherlands)

Schaafsma, M.; Brouwer, R.; Liekens, I.; de Nocker, L.

2014-01-01

The main objective of this paper is to test the temporal stability of stated preferences and willingness to pay (WTP) values from a Choice Experiment (CE) in a test-retest. The same group of participants was asked the same choice tasks in an internet-based CE, conducted twice with a time interval of

Portuguese-language version of the Chronic Respiratory Questionnaire: a validity and reproducibility study.

Science.gov (United States)

Moreira, Graciane Laender; Pitta, Fábio; Ramos, Dionei; Nascimento, Cinthia Sousa Carvalho; Barzon, Danielle; Kovelis, Demétria; Colange, Ana Lúcia; Brunetto, Antonio Fernando; Ramos, Ercy Mara Cipulo

2009-08-01

To determine the validity and reproducibility of a Portuguese-language version of the Chronic Respiratory Questionnaire (CRQ) in patients with COPD. A Portuguese-language version of the CRQ (provided by McMaster University, the holder of the questionnaire copyright) was applied to 50 patients with COPD (70 +/- 8 years of age; 32 males; FEV1 = 47 +/- 18% of predicted) on two occasions, one week apart. The CRQ has four domains (dyspnea, fatigue, emotional function, and mastery) and was applied as an interviewer-administered instrument. The Saint George's Respiratory Questionnaire (SGRQ), already validated for use in Brazil, was used as the criterion for validation. Spirometry and the six-minute walk test (6MWT) were performed to analyze the correlations with the CRQ scores. There were no significant CRQ test-retest differences (p > 0.05 for all domains). The test-retest intraclass correlation coefficient was 0.98, 0.97, 0.98 and 0.95 for the dyspnea, fatigue, emotional function and mastery domains, respectively. The Cronbach's alpha coefficient was 0.91. The CRQ domains correlated significantly with the SGRQ domains (-0.30 < r < -0.67; p < 0.05). There were no significant correlations between spirometric variables and the CRQ domains or between the CRQ domains and the 6MWT, with the exception of the fatigue domain (r = 0.30; p = 0.04). The Portuguese-language version of the CRQ proved to be reproducible and valid for use in Brazilian patients with COPD.

Test-retest reliability of the Clinical Learning Environment, Supervision and Nurse Teacher (CLES + T) scale.

Science.gov (United States)

Gustafsson, Margareta; Blomberg, Karin; Holmefur, Marie

2015-07-01

The Clinical Learning Environment, Supervision and Nurse Teacher (CLES + T) scale evaluates the student nurses' perception of the learning environment and supervision within the clinical placement. It has never been tested in a replication study. The aim of the present study was to evaluate the test-retest reliability of the CLES + T scale. The CLES + T scale was administered twice to a group of 42 student nurses, with a one-week interval. Test-retest reliability was determined by calculations of Intraclass Correlation Coefficients (ICCs) and weighted Kappa coefficients. Standard Error of Measurements (SEM) and Smallest Detectable Difference (SDD) determined the precision of individual scores. Bland-Altman plots were created for analyses of systematic differences between the test occasions. The results of the study showed that the stability over time was good to excellent (ICC 0.88-0.96) in the sub-dimensions "Supervisory relationship", "Pedagogical atmosphere on the ward" and "Role of the nurse teacher". Measurements of "Premises of nursing on the ward" and "Leadership style of the manager" had lower but still acceptable stability (ICC 0.70-0.75). No systematic differences occurred between the test occasions. This study supports the usefulness of the CLES + T scale as a reliable measure of the student nurses' perception of the learning environment within the clinical placement at a hospital. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Parsing Syllable Envelopes Test for Assessment of Amplitude Modulation Discrimination Skills in Children: Development, Normative Data, and Test-Retest Reliability Studies.

Science.gov (United States)

Cameron, Sharon; Chong-White, Nicky; Mealings, Kiri; Beechey, Tim; Dillon, Harvey; Young, Taegan

2018-02-01

Intensity peaks and valleys in the acoustic signal are salient cues to syllable structure, which is accepted to be a crucial early step in phonological processing. As such, the ability to detect low-rate (envelope) modulations in signal amplitude is essential to parse an incoming speech signal into smaller phonological units. The Parsing Syllable Envelopes (ParSE) test was developed to quantify the ability of children to recognize syllable boundaries using an amplitude modulation detection paradigm. The envelope of a 750-msec steady-state /a/ vowel is modulated into two or three pseudo-syllables using notches with modulation depths varying between 0% and 100% along an 11-step continuum. In an adaptive three-alternative forced-choice procedure, the participant identified whether one, two, or three pseudo-syllables were heard. Development of the ParSE stimuli and test protocols, and collection of normative and test-retest reliability data. Eleven adults (aged 23 yr 10 mo to 50 yr 9 mo, mean 32 yr 10 mo) and 134 typically developing, primary-school children (aged 6 yr 0 mo to 12 yr 4 mo, mean 9 yr 3 mo). There were 73 males and 72 females. Data were collected using a touchscreen computer. Psychometric functions (PFs) were automatically fit to individual data by the ParSE software. Performance was related to the modulation depth at which syllables can be detected with 88% accuracy (referred to as the upper boundary of the uncertainty region [UBUR]). A shallower PF slope reflected a greater level of uncertainty. Age effects were determined based on raw scores. z Scores were calculated to account for the effect of age on performance. Outliers, and individual data for which the confidence interval of the UBUR exceeded a maximum allowable value, were removed. Nonparametric tests were used as the data were skewed toward negative performance. Across participants, the performance criterion (UBUR) was met with a median modulation depth of 42%. The effect of age on the UBUR was

Reproducibility of Dual-Microphone Voice Range Profile Equipment

DEFF Research Database (Denmark)

Printz, Trine; Pedersen, Ellen Raben; Juhl, Peter

2017-01-01

in an anechoic chamber and an office: (a) comparing sound pressure levels (SPLs) from a dual-microphone VRP device, the Voice Profiler, when given the same input repeatedly (test-retest reliability); (b) comparing SPLs from 3 devices when given the same input repeatedly (intervariation); and (c) assessing...

Test-retest Agreement and Reliability of Quantitative Sensory Testing 1 Year After Breast Cancer Surgery

DEFF Research Database (Denmark)

Andersen, Kenneth Geving; Kehlet, Henrik; Aasvang, Eske Kvanner

2015-01-01

.5 SD) than within-patient variation (0.23 to 3.55 SD). There were no significant differences between pain and pain-free patients. The individual test-retest variability was higher on the operated side compared with the nonoperated side. DISCUSSION: The QST protocol reliability allows for group......OBJECTIVES: Quantitative sensory testing (QST) is used to assess sensory dysfunction and nerve damage by examining psychophysical responses to controlled, graded stimuli such as mechanical and thermal detection and pain thresholds. In the breast cancer population, 4 studies have used QST to examine...... persistent pain after breast cancer treatment, suggesting neuropathic pain being a prominent pain mechanism. However, the agreement and reliability of QST has not been described in the postsurgical breast cancer population, hindering exact interpretation of QST studies in this population. The aim...

Test-retest reliability and construct validity of the Helplessness, Hopelessness, and Haplessness Scale in patients with anxiety disorders.

Science.gov (United States)

Vatan, Sevginar; Ertaş, Sedar; Lester, David

2011-04-01

In a sample of 100 Turkish psychiatric patients with diagnoses of anxiety disorders, Lester's Helplessness, Hopelessness, and Haplessness inventory had moderate estimates of internal consistency, test-retest reliability, and construct validity.

Reproducibility of the results in ultrasonic testing

International Nuclear Information System (INIS)

Chalaye, M.; Launay, J.P.; Thomas, A.

1980-12-01

This memorandum reports on the conclusions of the tests carried out in order to evaluate the reproducibility of ultrasonic tests made on welded joints. FRAMATOME have started a study to assess the dispersion of results afforded by the test line and to characterize its behaviour. The tests covered sensors and ultrasonic generators said to be identical to each other (same commercial batch) [fr

The Physical Activity Scale for Individuals with Physical Disabilities : test-retest reliability and comparison with an accelerometer

NARCIS (Netherlands)

van der Ploeg, Hidde P; Streppel, Kitty R M; van der Beek, Allard J; van der Woude, Luc H V; Vollenbroek-Hutten, Miriam; van Mechelen, Willem; van der Woude, Lucas

BACKGROUND: The objective was to determine the test-retest reliability and criterion validity of the Physical Activity Scale for Individuals with Physical Disabilities (PASIPD). METHODS: Forty-five non-wheelchair dependent subjects were recruited from three Dutch rehabilitation centers. Subjects'

Construct Validity and Test-Retest Reliability of the Walking Questionnaire in People With a Lower Limb Amputation

NARCIS (Netherlands)

de Laat, Fred A.; Rommers, Gerardus M.; Geertzen, Jan H.; Roorda, Leo D.

Objective: To investigate the construct validity and test-retest reliability of the Walking Questionnaire, a patient-reported measure of activity limitations in walking in people with a lower limb amputation. Design: Cross-sectional study. Setting: Outpatient department of a rehabilitation center.

Imaging the norepinephrine transporter in humans with (S,S)-[11C]O-methyl reboxetine and PET: problems and progress

International Nuclear Information System (INIS)

Logan, Jean; Wang, Gene-jack; Telang, Frank; Fowler, Joanna S.; Alexoff, David; Zabroski, John; Jayne, Millard; Hubbard, Barbara; King, Payton; Carter, Pauline; Shea, Colleen; Xu, Youwen; Muench, Lisa; Schlyer, David; Learned-Coughlin, Susan; Cosson, Valerie; Volkow, Nora D.; Ding, Yu-shin

2007-01-01

Results from human studies with the PET radiotracer (S,S)-[ 11 C]O-methyl reboxetine ([ 11 C](S,S)-MRB), a ligand targeting the norepinephrine transporter (NET), are reported. Quantification methods were determined from test/retest studies, and sensitivity to pharmacological blockade was tested with different doses of atomoxetine (ATX), a drug that binds to the NET with high affinity (K i =2-5 nM). Methods: Twenty-four male subjects were divided into different groups for serial 90-min PET studies with [ 11 C](S,S)-MRB to assess reproducibility and the effect of blocking with different doses of ATX (25, 50 and 100 mg, po). Region-of-interest uptake data and arterial plasma input were analyzed for the distribution volume (DV). Images were normalized to a template, and average parametric images for each group were formed. Results: [ 11 C](S,S)-MRB uptake was highest in the thalamus (THL) and the midbrain (MBR) [containing the locus coeruleus (LC)] and lowest for the caudate nucleus (CDT). The CDT, a region with low NET, showed the smallest change on ATX treatment and was used as a reference region for the DV ratio (DVR). The baseline average DVR was 1.48 for both the THL and MBR with lower values for other regions [cerebellum (CB), 1.09; cingulate gyrus (CNG) 1.07]. However, more accurate information about relative densities came from the blocking studies. MBR exhibited greater blocking than THL, indicating a transporter density ∼40% greater than THL. No relationship was found between DVR change and plasma ATX level. Although the higher dose tended to induce a greater decrease than the lower dose for MBR (average decrease for 25 mg=24±7%; 100 mg=31±11%), these differences were not significant. The different blocking between MBR (average decrease=28±10%) and THL (average decrease=17±10%) given the same baseline DVR indicates that the CDT is not a good measure for non-NET binding in both regions. Threshold analysis of the difference between the average baseline DV

The importance of retesting the hearing screening as an indicator of the real early hearing disorder

Directory of Open Access Journals (Sweden)

Daniela Polo Camargo da Silva

2015-08-01

Full Text Available INTRODUCTION: Early diagnosis of hearing loss minimizes its impact on child development. We studied factors that influence the effectiveness of screening programs.OBJECTIVE: To investigate the relationship between gender, weight at birth, gestational age, risk factors for hearing loss, venue for newborn hearing screening and "pass" and "fail" results in the retest.METHODS: Prospective cohort study was carried out in a tertiary referral hospital. The screening was performed in 565 newborns through transient evoked otoacoustic emissions in three admission units before hospital discharge and retest in the outpatient clinic. Gender, weight at birth, gestational age, presence of risk indicators for hearing loss and venue for newborn hearing screening were considered.RESULTS: Full-term infants comprised 86% of the cases, preterm 14%, and risk factors for hearing loss were identified in 11%. Considering the 165 newborns retested, only the venue for screening, Intermediate Care Unit, was related to "fail" result in the retest.CONCLUSIONS: Gender, weight at birth, gestational age and presence of risk factors for hearing loss were not related to "pass" and/or "fail" results in the retest. The screening performed in intermediate care units increases the chance of continued "fail" result in the Transient Otoacoustic Evoked Emissions test.

Blowdown mass flow measurements during the Power Burst Facility LOC-11C test

International Nuclear Information System (INIS)

Broughton, J.M.; MacDonald, P.E.

1979-01-01

An interpretation and evaluation of the two-phase coolant mass flow measurements obtained during Test LOC-11C performed in the Power Burst Facility (PBF) at the Idaho National Engineering Laboratory (INEL) are presented. Although a density gradient existed within the pipe between 1 and 6 s, the homogeneous flow model used to calculate the coolant mass flow from the measured mixture density, momentum flux, and volumetric flow was found to be generally satisfactory. A cross-sectional average density was determined by fitting a linear density gradient through the upper and lower chordal densities obtained from a three-beam gamma densitometer and then combining the result with the middle beam density. The integrated measured coolant mass flow was subsequently found to be within 5% if the initial mass inventory of the PBF loss-of-coolant accident (LOCA) system. The posttest calculations using the RELAP4/MOD6 computer code to determine coolant mass flow for Test LOC-11C also agreed well with the measured data

Double-step processes in the 12C(p,d)11C reaction at 45 MeV

International Nuclear Information System (INIS)

Couvert, Pierre.

1974-01-01

12 C(p,d) 11 C pick-up reaction was performed with a 45 MeV proton beam. A 130keV energy resolution was obtained and angular distributions of nine of the ten first levels of 11 C have been extracted within a large angular range. Assuming only neutron direct transfert, the strong relative excitation of high spin levels cannot be reproduced by a DWBA analysis. The double-step process assumption seems to be verified by a systematical analysis of the (p,d) reaction mechanisms. This analysis is done in the coupled-channel formalism for the five first negative parity states of 11 C. The 3/2 - ground state is essentially populated by the direct transfer of a Psub(3/2) neutron. The contribution of a double-step process, via the 2 + inelastic excitation of 12 C, is important for the four other states. A mechanism which assumes a deuteron inelastic scattering on the 11 C final nucleus after the neutron transfer cannot be neglected and improves the fits when it is taken into account [fr

Work-related measures of physical and behavioral health function: Test-retest reliability.

Science.gov (United States)

Marino, Molly Elizabeth; Meterko, Mark; Marfeo, Elizabeth E; McDonough, Christine M; Jette, Alan M; Ni, Pengsheng; Bogusz, Kara; Rasch, Elizabeth K; Brandt, Diane E; Chan, Leighton

2015-10-01

The Work Disability Functional Assessment Battery (WD-FAB), developed for potential use by the US Social Security Administration to assess work-related function, currently consists of five multi-item scales assessing physical function and four multi-item scales assessing behavioral health function; the WD-FAB scales are administered as Computerized Adaptive Tests (CATs). The goal of this study was to evaluate the test-retest reliability of the WD-FAB Physical Function and Behavioral Health CATs. We administered the WD-FAB scales twice, 7-10 days apart, to a sample of 376 working age adults and 316 adults with work-disability. Intraclass correlation coefficients were calculated to measure the consistency of the scores between the two administrations. Standard error of measurement (SEM) and minimal detectable change (MDC90) were also calculated to measure the scales precision and sensitivity. For the Physical Function CAT scales, the ICCs ranged from 0.76 to 0.89 in the working age adult sample, and 0.77-0.86 in the sample of adults with work-disability. ICCs for the Behavioral Health CAT scales ranged from 0.66 to 0.70 in the working age adult sample, and 0.77-0.80 in the adults with work-disability. The SEM ranged from 3.25 to 4.55 for the Physical Function scales and 5.27-6.97 for the Behavioral Health function scales. For all scales in both samples, the MDC90 ranged from 7.58 to 16.27. Both the Physical Function and Behavioral Health CATs of the WD-FAB demonstrated good test-retest reliability in adults with work-disability and general adult samples, a critical requirement for assessing work related functioning in disability applicants and in other contexts. Copyright © 2015 Elsevier Inc. All rights reserved.

[11C]Doxepin binding to histamine H1 receptors in living human brain in association with attentive waking and circadian rhythm

Directory of Open Access Journals (Sweden)

Kazuhiko eYanai

2012-06-01

Full Text Available Molecular imaging in neuroscience is a new research field that enables visualization of the impact of molecular events on brain structure and function in humans. While magnetic resonance-based imaging techniques can provide complex information at the level of system, positron emission tomography (PET enables determination of the distribution and density of receptor and enzyme in the human brain. Previous studies using [11C]raclopride revealed that the release of neuronal dopamine was increased in human brain by psychostimulants or reward stimuli. Following on from these previous studies, we examined whether the levels of neuronal release of histamine might change [11C]doxepin binding to the H1 receptors under the influence of physiological stimuli. The purpose of the present study was to evaluate the test-retest reliability of quantitative measurement of [11C]doxepin binding between morning and afternoon and between resting and attentive waking conditions in healthy human subjects. There was a trend for a decrease in [11C]doxepin binding during attentive calculation tasks compared with that in resting conditions, but the difference (approximately 10% was not significant. In contrast, the binding potential of [11C]doxepin in the anterior cingulate gyrus was significantly higher in the morning than that in the afternoon (approximately 19%, suggesting that higher histamine release in the morning would decrease the [11C]doxepin binding in the afternoon. This study suggests that non-invasive measurement of neuronal histamine release is feasible in humans by PET ligand-activation study, although the development of a tracer with better signal-to-noise properties is needed.

11C-ORM-13070, a novel PET ligand for brain α2C-adrenoceptors: radiometabolism, plasma pharmacokinetics, whole-body distribution and radiation dosimetry in healthy men

International Nuclear Information System (INIS)

Luoto, Pauliina; Oikonen, Vesa; Arponen, Eveliina; Helin, Semi; Virta, Jere; Virtanen, Kirsi; Roivainen, Anne; Suilamo, Sami; Herttuainen, Jukka; Hietamaeki, Johanna; Holopainen, Aila; Rouru, Juha; Sallinen, Jukka; Kailajaervi, Marita; Peltonen, Juha M.; Scheinin, Mika; Volanen, Iina; Rinne, Juha O.

2014-01-01

11 C-labelled 1-[(S)-1-(2,3-dihydrobenzo[1,2]dioxin-2-yl)methyl] -4-(3-methoxy-methylpyridin-2- yl)-piperazine ( 11 C-ORM-13070) is a novel PET tracer for imaging of α 2C -adrenoceptors in the human brain. Brain α 2C -adrenoceptors may be therapeutic targets in several neuropsychiatric disorders, including depression, schizophrenia and Alzheimer's disease. To validate the use of 11 C-ORM-13070 in humans, we investigated its radiometabolism, pharmacokinetics, whole-body distribution and radiation dose. Radiometabolism was studied in a test-retest setting in six healthy men. After intravenous injection of 11 C-ORM-13070, blood samples were drawn over 60 min. Plasma samples were analysed by radio-HPLC for intact tracer and its radioactive metabolites. Metabolite-corrected plasma time-activity curves were used for calculation of pharmacokinetics. In a separate group of 12 healthy men, the whole-body distribution of 11 C-ORM-13070 and radiation exposure were investigated by dynamic PET/CT imaging without blood sampling. Two radioactive metabolites of 11 C-ORM-13070 were detected in human arterial plasma. The proportion of unchanged 11 C-ORM-13070 decreased from 81 ± 4 % of total radioactivity at 4 min after tracer injection to 23 ± 4 % at 60 min. At least one of the radioactive metabolites penetrated into red blood cells, while the parent tracer remained in plasma. The apparent elimination rate constant and corresponding half-life of unchanged 11 C-ORM-13070 in arterial plasma were 0.0117 ± 0.0056 min -1 and 73.6 ± 35.8 min, respectively. The organs with the highest absorbed doses were the liver (12 μSv/MBq), gallbladder wall (12 μSv/MBq) and pancreas (9.1 μSv/MBq). The mean effective dose was 3.9 μSv/MBq, with a range of 3.6 - 4.2 μSv/MBq. 11 C-ORM-13070 was rapidly metabolized in human subjects after intravenous injection. The effective radiation dose of 11 C-ORM-13070 was in the same range as that of other 11 C-labelled brain receptor tracers. An injection

Reproducibility and validity of the Nintendo Wii Balance Board for measuring shoulder sensorimotor control in prone lying.

Science.gov (United States)

Eshoj, H; Juul-Kristensen, Birgit; Jørgensen, Rene Gam Bender; Søgaard, Karen

2017-02-01

For the lower limbs, the Nintendo Wii Balance Board (NWBB) has been widely used to measure postural control. However, this has not been performed for upper limb measurements. Further, the NWBB has shown to produce more background noise with decreasing loads, which may be of concern when used for upper limb testing. The aim was to investigate reproducibility and validity of the NWBB. A test-retest design was performed with 68 subjects completing three different prone lying, upper limb weight-bearing balance tasks on a NWBB: two-arms, eyes closed (1) one-arm, non-dominant/non-injured (2) and one-arm, dominant/injured (3). Each task was repeated three times over the course of two test sessions with a 30-min break in between. Further, the level of background noise from a NWBB was compared with a force platform through systematic loading of both boards with increasing deadweights ranging from 5 to 90kg. Test-retest reproducibility was high with ICCs ranging from 0.95 to 0.97 (95% CI 0.92 to 0.98). However, systematic bias and tendencies for funnel effects in the Bland Altman plots for both one-armed tests were present. The concurrent validity of the NWBB was low (CCC 0.17 (95% CI 0.12-0.22)) due to large differences between the NWBB and force platform in noise sensitivity at low deadweights (especially below 50kg). The NWBB prone lying, shoulder sensorimotor control test was highly reproducible. Though, concurrent validity of the NWBB was poor compared to a force platform. Further investigation of the impact of the background noise, especially at low loads, is needed. Copyright © 2016 Elsevier B.V. All rights reserved.

Test--retest variability of Randot stereoacuity measures gathered in an unselected sample of UK primary school children.

Science.gov (United States)

Adler, Paul; Scally, Andrew J; Barrett, Brendan T

2012-05-01

To determine the test-retest reliability of the Randot stereoacuity test when used as part of vision screening in schools. Randot stereoacuity (graded-circles) and logMAR visual acuity measures were gathered in an unselected sample of 139 children (aged 4-12, mean 8.1±2.1 years) in two schools. Randot testing was repeated on two occasions (average interval between successive tests 8 days, range: 1-21 days). Three Randot scores were obtained in 97.8% of children. Randot stereoacuity improved by an average of one plate (ie, one test level) on repeat testing but was little changed when tested on the third occasion. Within-subject variability was up to three test levels on repeat testing. When stereoacuity was categorised as 'fine', 'intermediate' or 'coarse', the greatest variability was found among younger children who exhibited 'intermediate' or 'coarse'/nil stereopsis on initial testing. Whereas 90.8% of children with 'fine' stereopsis (≤50 arc-seconds) on the first test exhibited 'fine' stereopsis on both subsequent tests, only ∼16% of children with 'intermediate' (>50 but ≤140 arc-seconds) or 'coarse'/nil (≥200 arc-seconds) stereoacuity on initial testing exhibited stable test results on repeat testing. Children exhibiting abnormal stereoacuity on initial testing are very likely to exhibit a normal result when retested. The value of a single, abnormal Randot graded-circles stereoacuity measure from school screening is therefore questionable.

Reliability of the Swedish version of the Exercise Self-Efficacy Scale (S-ESES): a test-retest study in adults with neurological disease.

Science.gov (United States)

Ahlström, Isabell; Hellström, Karin; Emtner, Margareta; Anens, Elisabeth

2015-03-01

To examine the test-retest reliability of the Swedish translated version of the Exercise Self-Efficacy Scale (S-ESES) in people with neurological disease and to examine internal consistency. Test-retest study. A total of 30 adults with neurological diseases including: Parkinson's disease; Multiple Sclerosis; Cervical Dystonia; and Charcot-Marie-Tooth disease. The S-ESES was sent twice by surface mail. Completion interval mean was 16 days apart. Weighted kappa, intraclass correlation coefficient 2,1 [ICC (2,1)], standard error of measurement (SEM), also expressed as a percentage value (SEM%), and Cronbach's alpha were calculated. The relative reliability of the test-retest results showed substantial agreement measured using weighted kappa (MD = 0.62) and a very high-reliability ICC (2,1) (0.92). Absolute reliability measured using SEM was 5.3 and SEM% was 20.7. Excellent internal consistency was shown, with an alpha coefficient of 0.91 (test 1) and 0.93 (test 2). The S-ESES is recommended for use in research and in clinical work for people with neurological diseases. The low-absolute reliability, however, indicates a limited ability to measure changes on an individual level.

[DIN-compatible vision assessment of increased reproducibility using staircase measurement and maximum likelihood analysis].

Science.gov (United States)

Weigmann, U; Petersen, J

1996-08-01

Visual acuity determination according to DIN 58,220 does not make full use of the information received about the patient, in contrast to the staircase method. Thus, testing the same number of optotypes, the staircase method should yield more reproducible acuity results. On the other hand, the staircase method gives systematically higher acuity values because it converges on the 48% point of the psychometric function (for Landolt rings in eight positions) and not on the 65% probability, as DIN 58,220 with criterion 3/5 does. This bias can be avoided by means of a modified evaluation. Using the staircase data we performed a maximum likelihood estimate of the psychometric function as a whole and computed the acuity value for 65% probability of correct answers. We determined monocular visual acuity in 102 persons with widely differing visual performance. Each subject underwent four tests in random order, two according to DIN 58,220 and two using the modified staircase method (Landolt rings in eight positions scaled by a factor 1.26; PC monitor with 1024 x 768 pixels; distance 4.5 m). Each test was performed with 25 optotypes. The two procedures provide the same mean visual acuity values (difference less than 0.02 acuity steps). The test-retest results match in 30.4% of DIN repetitions but in 50% of the staircases. The standard deviation of the test-retest difference is 1.41 (DIN) and 1.06 (modified staircase) acuity steps. Thus the standard deviation of the single test is 1.0 (DIN) and 0.75 (modified staircase) acuity steps. The new method provides visual acuity values identical to DIN 58,220 but is superior with respect to reproducibility.

14 CFR 61.49 - Retesting after failure.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Retesting after failure. 61.49 Section 61.49 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... failure. (a) An applicant for a knowledge or practical test who fails that test may reapply for the test...

A reproducible accelerated in vitro release testing method for PLGA microspheres.

Science.gov (United States)

Shen, Jie; Lee, Kyulim; Choi, Stephanie; Qu, Wen; Wang, Yan; Burgess, Diane J

2016-02-10

The objective of the present study was to develop a discriminatory and reproducible accelerated in vitro release method for long-acting PLGA microspheres with inner structure/porosity differences. Risperidone was chosen as a model drug. Qualitatively and quantitatively equivalent PLGA microspheres with different inner structure/porosity were obtained using different manufacturing processes. Physicochemical properties as well as degradation profiles of the prepared microspheres were investigated. Furthermore, in vitro release testing of the prepared risperidone microspheres was performed using the most common in vitro release methods (i.e., sample-and-separate and flow through) for this type of product. The obtained compositionally equivalent risperidone microspheres had similar drug loading but different inner structure/porosity. When microsphere particle size appeared similar, porous risperidone microspheres showed faster microsphere degradation and drug release compared with less porous microspheres. Both in vitro release methods investigated were able to differentiate risperidone microsphere formulations with differences in porosity under real-time (37 °C) and accelerated (45 °C) testing conditions. Notably, only the accelerated USP apparatus 4 method showed good reproducibility for highly porous risperidone microspheres. These results indicated that the accelerated USP apparatus 4 method is an appropriate fast quality control tool for long-acting PLGA microspheres (even with porous structures). Copyright © 2015 Elsevier B.V. All rights reserved.

The Phoneme Identification Test for Assessment of Spectral and Temporal Discrimination Skills in Children: Development, Normative Data, and Test-Retest Reliability Studies.

Science.gov (United States)

Cameron, Sharon; Chong-White, Nicky; Mealings, Kiri; Beechey, Tim; Dillon, Harvey; Young, Taegan

2018-02-01

Previous research suggests that a proportion of children experiencing reading and listening difficulties may have an underlying primary deficit in the way that the central auditory nervous system analyses the perceptually important, rapidly varying, formant frequency components of speech. The Phoneme Identification Test (PIT) was developed to investigate the ability of children to use spectro-temporal cues to perceptually categorize speech sounds based on their rapidly changing formant frequencies. The PIT uses an adaptive two-alternative forced-choice procedure whereby the participant identifies a synthesized consonant-vowel (CV) (/ba/ or /da/) syllable. CV syllables differed only in the second formant (F2) frequency along an 11-step continuum (between 0% and 100%-representing an ideal /ba/ and /da/, respectively). The CV syllables were presented in either quiet (PIT Q) or noise at a 0 dB signal-to-noise ratio (PIT N). Development of the PIT stimuli and test protocols, and collection of normative and test-retest reliability data. Twelve adults (aged 23 yr 10 mo to 50 yr 9 mo, mean 32 yr 5 mo) and 137 typically developing, primary-school children (aged 6 yr 0 mo to 12 yr 4 mo, mean 9 yr 3 mo). There were 73 males and 76 females. Data were collected using a touchscreen computer. Psychometric functions were automatically fit to individual data by the PIT software. Performance was determined by the width of the continuum for which responses were neither clearly /ba/ nor /da/ (referred to as the uncertainty region [UR]). A shallower psychometric function slope reflected greater uncertainty. Age effects were determined based on raw scores. Z scores were calculated to account for the effect of age on performance. Outliers, and individual data for which the confidence interval of the UR exceeded a maximum allowable value, were removed. Nonparametric tests were used as the data were skewed toward negative performance. Across participants, the median value of the F2 range

Opioid receptor imaging and displacement studies with [6-O-[11C]methyl]buprenorphine in baboon brain

International Nuclear Information System (INIS)

Galynker, Igor; Schlyer, David J.; Dewey, Stephen L.; Fowler, Joanna S.; Logan, Jean; Gatley, S. John; MacGregor, Robert R.; Ferrieri, Richard A.; Holland, M. J.; Brodie, Jonathan; Simon, Eric; Wolf, Alfred P.

1996-01-01

Buprenorphine (BPN) is a mixed opiate agonist-antagonist used as an analgesic and in the treatment of opiate addiction. We have used [6-O-[ 11 C]methyl]buprenorphine ([ 11 C]BPN) to measure the regional distribution in baboon brain, the test-retest stability of repeated studies in the same animal, the displacement of the labeled drug by naloxone in vivo, and the tissue distribution in mice. The regional distribution of radioactivity in baboon brain determined with PET was striatum > thalamus > cingulate gyrus > frontal cortex > parietal cortex > occipital cortex > cerebellum. This distribution corresponded to opiate receptor density and to previously published data (37). The tracer uptake in adult female baboons showed no significant variation in serial scans in the same baboon with no intervention in the same scanning session. HPLC analysis of baboon plasma showed the presence of labeled metabolites with 92% ± 2.2% and 43% ± 14.4% of the intact tracer remaining at 5 and 30 min, respectively. Naloxone, an opiate receptor antagonist, administered 30-40 min after tracer injection at a dose of 1.0 mg/kg i.v., reduced [ 11 C]BPN binding in thalamus, striatum, cingulate gyrus, and frontal cortex to values 0.25 to 0.60 of that with no intervention. There were minimal ( 11 C]BPN can be displaced by naloxone in vivo, and they affirm the feasibility of using this tracer and displacement methodology for short-term kinetics studies with PET. Mouse tissue distribution data were used to estimate the radiation dosimetry to humans. The critical organ was the small intestine, with a radiation dose estimate to humans of 117 nrad/mCi

Test-retest reliability of a handheld dynamometer for measurement of isometric cervical muscle strength.

Science.gov (United States)

Vannebo, Katrine Tranaas; Iversen, Vegard Moe; Fimland, Marius Steiro; Mork, Paul Jarle

2018-03-02

There is a lack of test-retest reliability studies of measurements of cervical muscle strength, taking into account gender and possible learning effects. To investigate test-retest reliability of measurement of maximal isometric cervical muscle strength by handheld dynamometry. Thirty women (age 20-58 years) and 28 men (age 20-60 years) participated in the study. Maximal isometric strength (neck flexion, neck extension, and right/left lateral flexion) was measured on three separate days at least five days apart by one evaluator. Intra-rater consistency tended to improve from day 1-2 measurements to day 2-3 measurements in both women and men. In women, the intra-class correlation coefficients (ICC) for day 2 to day 3 measurements were 0.91 (95% confidence interval [CI], 0.82-0.95) for neck flexion, 0.88 (95% CI, 0.76-0.94) for neck extension, 0.84 (95% CI, 0.68-0.92) for right lateral flexion, and 0.89 (95% CI, 0.78-0.95) for left lateral flexion. The corresponding ICCs among men were 0.86 (95% CI, 0.72-0.93) for neck flexion, 0.93 (95% CI, 0.85-0.97) for neck extension, 0.82 (95% CI, 0.65-0.91) for right lateral flexion and 0.73 (95% CI, 0.50-0.87) for left lateral flexion. This study describes a reliable and easy-to-administer test for assessing maximal isometric cervical muscle strength.

Imaging the norepinephrine transporter in humans with (S,S)-[{sup 11}C]O-methyl reboxetine and PET: problems and progress

Energy Technology Data Exchange (ETDEWEB)

Logan, Jean [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)], E-mail: logan@bnl.gov; Wang, Gene-jack; Telang, Frank; Fowler, Joanna S.; Alexoff, David; Zabroski, John; Jayne, Millard; Hubbard, Barbara; King, Payton; Carter, Pauline; Shea, Colleen; Xu, Youwen; Muench, Lisa; Schlyer, David [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Learned-Coughlin, Susan; Cosson, Valerie [GlaxoSmithKline, Research Triangle Park, NC 27709 (United States); Volkow, Nora D. [National Institute on Drug Abuse, Bethesda, MD 20892 (United States); Ding, Yu-shin [Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT 06520-8048 (United States)

2007-08-15

Results from human studies with the PET radiotracer (S,S)-[{sup 11}C]O-methyl reboxetine ([{sup 11}C](S,S)-MRB), a ligand targeting the norepinephrine transporter (NET), are reported. Quantification methods were determined from test/retest studies, and sensitivity to pharmacological blockade was tested with different doses of atomoxetine (ATX), a drug that binds to the NET with high affinity (K{sub i}=2-5 nM). Methods: Twenty-four male subjects were divided into different groups for serial 90-min PET studies with [{sup 11}C](S,S)-MRB to assess reproducibility and the effect of blocking with different doses of ATX (25, 50 and 100 mg, po). Region-of-interest uptake data and arterial plasma input were analyzed for the distribution volume (DV). Images were normalized to a template, and average parametric images for each group were formed. Results: [{sup 11}C](S,S)-MRB uptake was highest in the thalamus (THL) and the midbrain (MBR) [containing the locus coeruleus (LC)] and lowest for the caudate nucleus (CDT). The CDT, a region with low NET, showed the smallest change on ATX treatment and was used as a reference region for the DV ratio (DVR). The baseline average DVR was 1.48 for both the THL and MBR with lower values for other regions [cerebellum (CB), 1.09; cingulate gyrus (CNG) 1.07]. However, more accurate information about relative densities came from the blocking studies. MBR exhibited greater blocking than THL, indicating a transporter density {approx}40% greater than THL. No relationship was found between DVR change and plasma ATX level. Although the higher dose tended to induce a greater decrease than the lower dose for MBR (average decrease for 25 mg=24{+-}7%; 100 mg=31{+-}11%), these differences were not significant. The different blocking between MBR (average decrease=28{+-}10%) and THL (average decrease=17{+-}10%) given the same baseline DVR indicates that the CDT is not a good measure for non-NET binding in both regions. Threshold analysis of the

Inter-examiner reproducibility of tests for lumbar motor control

Directory of Open Access Journals (Sweden)

Elkjaer Arne

2011-05-01

Full Text Available Abstract Background Many studies show a relation between reduced lumbar motor control (LMC and low back pain (LBP. However, test circumstances vary and during test performance, subjects may change position. In other words, the reliability - i.e. reproducibility and validity - of tests for LMC should be based on quantitative data. This has not been considered before. The aim was to analyse the reproducibility of five different quantitative tests for LMC commonly used in daily clinical practice. Methods The five tests for LMC were: repositioning (RPS, sitting forward lean (SFL, sitting knee extension (SKE, and bent knee fall out (BKFO, all measured in cm, and leg lowering (LL, measured in mm Hg. A total of 40 subjects (14 males, 26 females 25 with and 15 without LBP, with a mean age of 46.5 years (SD 14.8, were examined independently and in random order by two examiners on the same day. LBP subjects were recruited from three physiotherapy clinics with a connection to the clinic's gym or back-school. Non-LBP subjects were recruited from the clinic's staff acquaintances, and from patients without LBP. Results The means and standard deviations for each of the tests were 0.36 (0.27 cm for RPS, 1.01 (0.62 cm for SFL, 0.40 (0.29 cm for SKE, 1.07 (0.52 cm for BKFO, and 32.9 (7.1 mm Hg for LL. All five tests for LMC had reproducibility with the following ICCs: 0.90 for RPS, 0.96 for SFL, 0.96 for SKE, 0.94 for BKFO, and 0.98 for LL. Bland and Altman plots showed that most of the differences between examiners A and B were less than 0.20 cm. Conclusion These five tests for LMC displayed excellent reproducibility. However, the diagnostic accuracy of these tests needs to be addressed in larger cohorts of subjects, establishing values for the normal population. Also cut-points between subjects with and without LBP must be determined, taking into account age, level of activity, degree of impairment and participation in sports. Whether reproducibility of these

Test-retest reliability and comparability of paper and computer questionnaires for the Finnish version of the Tampa Scale of Kinesiophobia.

Science.gov (United States)

Koho, P; Aho, S; Kautiainen, H; Pohjolainen, T; Hurri, H

2014-12-01

To estimate the internal consistency, test-retest reliability and comparability of paper and computer versions of the Finnish version of the Tampa Scale of Kinesiophobia (TSK-FIN) among patients with chronic pain. In addition, patients' personal experiences of completing both versions of the TSK-FIN and preferences between these two methods of data collection were studied. Test-retest reliability study. Paper and computer versions of the TSK-FIN were completed twice on two consecutive days. The sample comprised 94 consecutive patients with chronic musculoskeletal pain participating in a pain management or individual rehabilitation programme. The group rehabilitation design consisted of physical and functional exercises, evaluation of the social situation, psychological assessment of pain-related stress factors, and personal pain management training in order to regain overall function and mitigate the inconvenience of pain and fear-avoidance behaviour. The mean TSK-FIN score was 37.1 [standard deviation (SD) 8.1] for the computer version and 35.3 (SD 7.9) for the paper version. The mean difference between the two versions was 1.9 (95% confidence interval 0.8 to 2.9). Test-retest reliability was 0.89 for the paper version and 0.88 for the computer version. Internal consistency was considered to be good for both versions. The intraclass correlation coefficient for comparability was 0.77 (95% confidence interval 0.66 to 0.85), indicating substantial reliability between the two methods. Both versions of the TSK-FIN demonstrated substantial intertest reliability, good test-retest reliability, good internal consistency and acceptable limits of agreement, suggesting their suitability for clinical use. However, subjects tended to score higher when using the computer version. As such, in an ideal situation, data should be collected in a similar manner throughout the course of rehabilitation or clinical research. Copyright © 2014 Chartered Society of Physiotherapy. Published

Test-retest reliability of the Food Allergy Quality of Life Questionnaires (FAQLQ) for children, adolescents and adults

NARCIS (Netherlands)

van der Velde, Jantina L.; Flokstra-de Blok, Bertine M. J.; Vlieg - Boerstra, Berber J.; Oude Elberink, Joanne N. G.; Schouten, Jan P.; DunnGalvin, Audrey; Hourihane, Jonathan O'B; Duiverman, Eric J.; Dubois, Anthony E. J.

The self-administered Food Allergy Quality of Life Questionnaire-Child Form (FAQLQ-CF), -Teenager Form (FAQLQ-TF) and -Adult Form (FAQLQ-AF) were recently developed within EuroPrevall, a multi-centred study of food allergy in Europe. The primary aim of this study was to evaluate the test-retest

Test-retest reliability of the Food Allergy Quality of Life Questionnaires (FAQLQ) for children, adolescents and adults

NARCIS (Netherlands)

van der Velde, Jantina L.; Flokstra-de Blok, Bertine M. J.; Vlieg-Boerstra, Berber J.; Oude Elberink, Joanne N. G.; Schouten, Jan P.; DunnGalvin, Audrey; Hourihane, Jonathan O.'B.; Duiverman, Eric J.; Dubois, Anthony E. J.

2009-01-01

The self-administered Food Allergy Quality of Life Questionnaire-Child Form (FAQLQ-CF), -Teenager Form (FAQLQ-TF) and -Adult Form (FAQLQ-AF) were recently developed within EuroPrevall, a multi-centred study of food allergy in Europe. The primary aim of this study was to evaluate the test-retest

The eye-complaint questionnaire in a visual display unit work environment: Internal consistency and test-retest reliability

NARCIS (Netherlands)

Steenstra, Ivan A.; Sluiter, Judith K.; Frings-Dresen, Monique H. W.

2009-01-01

The internal consistency and test-retest reliability of a 10-item eye-complaint questionnaire (ECQ) were examined within a sample of office workers. Repeated within-subjects measures were performed within a single day and over intervals of 1 and 7 d. Questionnaires were completed by 96 workers (70%

Brain GABA Detection in vivo with the J-editing 1H MRS Technique: A Comprehensive Methodological Evaluation of Sensitivity Enhancement, Macromolecule Contamination and Test-Retest Reliability

Science.gov (United States)

Shungu, Dikoma C.; Mao, Xiangling; Gonzales, Robyn; Soones, Tacara N.; Dyke, Jonathan P.; van der Veen, Jan Willem; Kegeles, Lawrence S.

2016-01-01

Abnormalities in brain γ-aminobutyric acid (GABA) have been implicated in various neuropsychiatric and neurological disorders. However, in vivo GABA detection by proton magnetic resonance spectroscopy (1H MRS) presents significant challenges arising from low brain concentration, overlap by much stronger resonances, and contamination by mobile macromolecule (MM) signals. This study addresses these impediments to reliable brain GABA detection with the J-editing difference technique on a 3T MR system in healthy human subjects by (a) assessing the sensitivity gains attainable with an 8-channel phased-array head coil, (b) determining the magnitude and anatomic variation of the contamination of GABA by MM, and (c) estimating the test-retest reliability of measuring GABA with this method. Sensitivity gains and test-retest reliability were examined in the dorsolateral prefrontal cortex (DLPFC), while MM levels were compared across three cortical regions: the DLPFC, the medial prefrontal cortex (MPFC) and the occipital cortex (OCC). A 3-fold higher GABA detection sensitivity was attained with the 8-channel head coil compared to the standard single-channel head coil in DLPFC. Despite significant anatomic variation in GABA+MM and MM across the three brain regions (p GABA+MM was relatively stable across the three voxels, ranging from 41% to 49%, a non-significant regional variation (p = 0.58). The test-retest reliability of GABA measurement, expressed either as ratios to voxel tissue water (W) or total creatine, was found to be very high for both the single-channel coil and the 8-channel phased-array coil. For the 8-channel coil, for example, Pearson’s correlation coefficient of test vs. retest for GABA/W was 0.98 (R2 = 0.96, p = 0.0007), the percent coefficient of variation (CV) was 1.25%, and the intraclass correlation coefficient (ICC) was 0.98. Similar reliability was also found for the co-edited resonance of combined glutamate and glutamine (Glx) for both coils. PMID

Rationale and design of REACT: a randomised controlled trial assessing the effectiveness of home-collection to increase chlamydia retesting and detect repeat positive tests.

Science.gov (United States)

Smith, Kirsty S; Hocking, Jane S; Chen, Marcus; Fairley, Christopher K; McNulty, Anna; Read, Phillip; Bradshaw, Catriona S; Tabrizi, Sepehr N; Wand, Handan; Saville, Marion; Rawlinson, William; Garland, Suzanne M; Donovan, Basil; Kaldor, John M; Guy, Rebecca

2014-04-24

Repeat infection with Chlamydia trachomatis is common and increases the risk of sequelae in women and HIV seroconversion in men who have sex with men (MSM). Despite guidelines recommending chlamydia retesting three months after treatment, retesting rates are low. We are conducting the first randomised controlled trial to assess the effectiveness of home collection combined with short message service (SMS) reminders on chlamydia retesting and reinfection rates in three risk groups. The REACT (retest after Chlamydia trachomatis) trial involves 600 patients diagnosed with chlamydia: 200 MSM, 200 women and 200 heterosexual men recruited from two Australian sexual health clinics where SMS reminders for retesting are routine practice. Participants will be randomised to the home group (3-month SMS reminder and home-collection) or the clinic group (3-month SMS reminder to return to the clinic). Participants in the home group will be given the choice of attending the clinic if they prefer. The mailed home-collection kit includes a self-collected vaginal swab (women), UriSWAB (Copan) for urine collection (heterosexual men), and UriSWAB plus rectal swab (MSM). The primary outcome is the retest rate at 1-4 months after a chlamydia diagnosis, and the secondary outcomes are: the repeat positive test rate; the reinfection rate; the acceptability of home testing with SMS reminders; and the cost effectiveness of home testing. Sexual behaviour data collected via an online survey at 4-5 months, and genotyping of repeat infections, will be used to discriminate reinfections from treatment failures. The trial will be conducted over two years. An intention to treat analysis will be conducted. This study will provide evidence about the effectiveness of home-collection combined with SMS reminders on chlamydia retesting, repeat infection and reinfection rates in three risk groups. The trial will determine client acceptability and cost effectiveness of this strategy. Australian and New

14 CFR 63.41 - Retesting after failure.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Retesting after failure. 63.41 Section 63.41 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... failure. An applicant for a flight engineer certificate who fails a written test or practical test for...

Quick look report for semiscale MOD-2C Test S-FS-11

International Nuclear Information System (INIS)

Plessinger, M.P.

1985-11-01

Results of a preliminary analysis of the fifth test performed in the Semiscale MOD-2C Steam Generator Feedwater and Steam Line Break (FS) experiment series are presented. Test S-FS-11 simulated a pressurized water reactor transient initiated by a 50% break in a steam generator bottom feedwater line downstream of the check valve. With the exception of primary pressure, the initial conditions represented the initial conditions used for the C-E System 80 Final Safety Analysis Report (FSAR) Appendix 15B calculations. The transient included an initial 600 s period in which only automatic plant protection systems responded to the initiating event. This period was followed by a series of operator actions necessary to stabilize the plant followed by break isolation and affected loop steam generator refill with auxiliary feedwater. The test results provided a measured evaluation of the effectiveness of the automatic responses in minimizing primary system overpressurization and operator actions in stabilizing the plant. Test data also provided a basis for comparison with other tests in the series of the effects of break size on primary overpressurization and primary-to-secondary heat transfer. 64 figs

Test-Retest Reliability of the Parent Behavior Importance Questionnaire-Revised and the Parent Behavior Frequency Questionnaire-Revised

Science.gov (United States)

Mowder, Barbara A.; Shamah, Renee

2011-01-01

This study evaluated the test-retest reliability of two parenting measures: the Parent Behavior Importance Questionnaire-Revised (PBIQ-R) and Parent Behavior Frequency Questionnaire-Revised (PBFQ-R). These self-report parenting behavior assessment measures may be utilized as pre- and post-parent education program measures, with parents as well as…

Processing and Prolonged 500 C Testing of 4H-SiC JFET Integrated Circuits with Two Levels of Metal Interconnect

Science.gov (United States)

Spry, David J.; Neudeck, Philip G.; Chen, Liangyu; Lukco, Dorothy; Chang, Carl W.; Beheim, Glenn M.; Krasowski, Michael J.; Prokop, Norman F.

2015-01-01

Complex integrated circuit (IC) chips rely on more than one level of interconnect metallization for routing of electrical power and signals. This work reports the processing and testing of 4H-SiC junction field effect transistor (JFET) prototype IC's with two levels of metal interconnect capable of prolonged operation at 500 C. Packaged functional circuits including 3- and 11-stage ring oscillators, a 4-bit digital to analog converter, and a 4-bit address decoder and random access memory cell have been demonstrated at 500 C. A 3-stage oscillator functioned for over 3000 hours at 500 C in air ambient. Improved reproducibility remains to be accomplished.

Test-retest reliability and practice effects of the Wechsler Memory Scale-III.

Science.gov (United States)

Lo, Ada H Y; Humphreys, Michael; Byrne, Gerard J; Pachana, Nancy A

2012-09-01

Although serial administration of cognitive tests is increasingly common, there is a paucity of research on test-retest reliabilities and practice effects, both of which are important for evaluating changes in functioning. Reliability is generally conceptualized as involving short-lasting changes in performance. However, when repeated testing occurs over a period of years, there will be some longer lasting effects. The implications of these longer lasting effects and practice effects on reliability were examined in the context of repeated administrations of the Wechsler Memory Scale-III in 339 community-dwelling women aged 40-79 years over 2 to 7 years. The results showed that Logical Memory and Verbal Paired Associates subtests were consistently the most reliable subtests across the age cohorts. The magnitude of practice effects varied as a function of subtests and age. The largest practice effects were found in the youngest age cohort, especially on the Faces, Logical Memory, and Verbal Paired Associates subtests. ©2012 The British Psychological Society.

Test-retest repeatability of child's respiratory symptoms and perceived indoor air quality - comparing self- and parent-administered questionnaires.

Science.gov (United States)

Lampi, Jussi; Ung-Lanki, Sari; Santalahti, Päivi; Pekkanen, Juha

2018-02-09

Questionnaires can be used to assess perceived indoor air quality and symptoms in schools. Questionnaires for primary school aged children have traditionally been parent-administered, but self-administered questionnaires would be easier to administer and may yield as good, if not better, information. Our aim was to compare the repeatability of self- and parent-administered indoor air questionnaires designed for primary school aged pupils. Indoor air questionnaire with questions on child's symptoms and perceived indoor air quality in schools was sent to parents of pupils aged 7-12 years in two schools and again after two weeks. Slightly modified version of the questionnaire was administered to pupils aged 9-12 years in another two schools and repeated after a week. 351 (52%) parents and 319 pupils (86%) answered both the first and the second questionnaire. Test-retest repeatability was assessed with intra-class correlation (ICC) and Cohen's kappa coefficients (k). Test-retest repeatability was generally between 0.4-0.7 (ICC; k) in both self- and parent-administered questionnaire. In majority of the questions on symptoms and perceived indoor air quality test-retest repeatability was at the same level or slightly better in self-administered compared to parent-administered questionnaire. Agreement of self- and parent administered questionnaires was generally indoor air quality. Children aged 9-12 years can give as, or even more, repeatable information about their respiratory symptoms and perceived indoor air quality than their parents. Therefore, it may be possible to use self-administered questionnaires in future studies also with children.

Automated preparation of the dopamine D{sub 2/3} receptor agonist ligand [{sup 11}C]-(+)-PHNO for human PET imaging studies

Energy Technology Data Exchange (ETDEWEB)

Plisson, Christophe, E-mail: Christophe.2.plisson@gsk.com [GlaxoSmithKline, Clinical Imaging Centre, Hammersmith Hospital, London W12 0NN (United Kingdom); Huiban, Mickael; Pampols-Maso, Sabina; Singleton, Goerkem; Hill, Samuel P.; Passchier, Jan [GlaxoSmithKline, Clinical Imaging Centre, Hammersmith Hospital, London W12 0NN (United Kingdom)

2012-02-15

Carbon-11 labelled (+)-4-Propyl-3,4,4a,5,6,10b-hexahydro-2H-naphtho[1,2-b][1,4]oxazin-9-ol ([{sup 11}C]-(+)-PHNO) is used as a high-affinity state, dopamine D{sub 2/3} receptor ligand in clinical PET studies. To facilitate its use, robust, rapid, efficient and GMP compliant methods are required for the manufacturing and QC testing processes. Additionally, to allow for full quantification of the resulting signal in the CNS, a reliable method is required to establish the parent plasma concentration over the course of the scan. This paper provides high-quality methods to support clinical application of [{sup 11}C]-(+)-PHNO. - Highlights: Black-Right-Pointing-Pointer Fully automated synthesis of [{sup 11}C]-(+)-PHNO. Black-Right-Pointing-Pointer Rapid multi-step synthesis and QC analysis. Black-Right-Pointing-Pointer Reproducible synthesis process typically yielding more than 3 GBq of [{sup 11}C]-(+)-PHNO. Black-Right-Pointing-Pointer Very low failure rate.

Synthesis of racemic [3-11C]phenylalanine and [3-11C] DOPA

International Nuclear Information System (INIS)

Halldin, C.; Laangstroem, B.

1984-01-01

The synthesis of racemic [3- 11 C]phenylalanine and [3- 11 C]DOPA is reported. The [ 11 C]benzaldehyde and [ 11 C]veratraldehyde prepared in a two-step reaction from the corresponding [ 11 C]acid salt and [ 11 C]alcohol, by means of selective oxidation with tetrabutylammonium hydrogen chromate, were reacted with 2-phenyl-5-oxazolone or 2-(4-chloro)phenyl-5-oxazolone in the presence of a tertiary amine to give the corresponding [α- 11 C]-4-arylene-2-aryl-5-oxazolones. Ring opening of these olefins, hydrogenation, and removal of protecting groups was carried out in one step using hydroiodic cid/phosphorus, with the production of the racemic [3- 11 C]amino acids in 8-30% radiochemical yield (starting with 11 CO 2 ) within 52-60 min (including LC separation). (author)

Test-retest reliability of Antonovsky's 13-item sense of coherence scale in patients with hand-related disorders

DEFF Research Database (Denmark)

Hansen, Alice Ørts; Kristensen, Hanne Kaae; Cederlund, Ragnhild

2017-01-01

to be a powerful tool to measure the ICF component personal factors, which could have an impact on patients' rehabilitation outcomes. Implications for rehabilitation Antonovsky's SOC-13 scale showed test-retest reliability for patients with hand-related disorders. The SOC-13 scale could be a suitable tool to help...... measure personal factors....

Test Re-Test Reliability of Four Versions of the 3-Cone Test in Non-Athletic Men

Directory of Open Access Journals (Sweden)

Jason G. Langley, Robert D. Chetlin

2017-03-01

Full Text Available Until recently, measurement and evaluation in sport science, especially agility testing, has not always included key elements of proper test construction. Often tests are published without reporting reliability and validity analysis for a specific population. The purpose of the present study was to examine the test re-test reliability of four versions of the 3-Cone Test (3CT, and provide guidance on proper test construction for testing agility in athletic populations. Forty male students enrolled in classes in the Department of Physical Education at a mid-Atlantic university participated. On each of test day participants performed 10 trials. In random order, they performed three trials to the right (3CTR, standard test, three to the left (3CTL, and two modified trials (3CTAR and 3CTAL, which included a reactive component in which a visual cue was given to indicate direction. Intra-class correlation coefficients (ICC indicated a moderate to high reliability for the four tests, 3CTR 0.79 (0.64-0.88, 95%CI, 3CTL 0.73 (0.55-0.85, 3CTAR 0.85(0.74-0.92, and 3CTAL 0.79 (0.64-0.88. Small standard error of the measurement (SEM was found; range 0.09 to 0.10. Pearson correlations between tests were high (0.82-0.92 on day one as well as day two (0.72-0.85. These results indicate each version of the 3-Cone Test is reliable; however, further tests are needed with specific athletic populations. Only the 3CTAR and 3CTAL are tests of agility due to the inclusion of a reactive component. Future studies examining agility testing and training should incorporate technological elements, including automated timing systems and motion capture analysis. Such instrumentation will allow for optimal design of tests that simulate sport-specific game conditions.

Comparative test-retest reliability of metabolite values assessed with magnetic resonance spectroscopy of the brain. The LCModel versus the manufacturer software.

Science.gov (United States)

Fayed, Nicolas; Modrego, Pedro J; Medrano, Jaime

2009-06-01

Reproducibility is an essential strength of any diagnostic technique for cross-sectional and longitudinal works. To determine in vivo short-term comparatively, the test-retest reliability of magnetic resonance spectroscopy (MRS) of the brain was compared using the manufacturer's software package and the widely used linear combination of model (LCModel) technique. Single-voxel H-MRS was performed in a series of patients with different pathologies on a 1.5 T clinical scanner. Four areas of the brain were explored with the point resolved spectroscopy technique acquisition mode; the echo time was 35 milliseconds and the repetition time was 2000 milliseconds. We enrolled 15 patients for every area, and the intra-individual variations of metabolites were studied in two consecutive scans without removing the patient from the scanner. Curve fitting and analysis of metabolites were made with the software of GE and the LCModel. Spectra non-fulfilling the minimum criteria of quality in relation to linewidths and signal/noise ratio were rejected. The intraclass correlation coefficients for the N-acetylaspartate/creatine (NAA/Cr) ratios were 0.93, 0.89, 0.9 and 0.8 for the posterior cingulate gyrus, occipital, prefrontal and temporal regions, respectively, with the GE software. For the LCModel, the coefficients were 0.9, 0.89, 0.87 and 0.84, respectively. For the absolute value of NAA, the GE software was also slightly more reproducible than LCModel. However, for the choline/Cr and myo-inositol/Cr ratios, the LCModel was more reliable than the GE software. The variability we have seen hovers around the percentages observed in previous reports (around 10% for the NAA/Cr ratios). We did not find that the LCModel software is superior to the software of the manufacturer. Reproducibility of metabolite values relies more on the observance of the quality parameters than on the software used.

Reproducibility of proximal and distal transcutaneous oxygen pressure measurements during exercise in stage 2 arterial claudication.

Science.gov (United States)

Bouyé, P; Picquet, J; Jaquinandi, V; Enon, B; Leftheriotis, G; Saumet, J-L; Abraham, P

2004-06-01

Although transcutaneous oxygen pressure measurements (tcpO2) are largely used in the investigation of vascular patients, its reproducibility is still debated. Indeed an unpredictable gradient exists between arterial and transcutaneous oxygen pressure. We hypothesised that indices taking into account changes over time and independent of absolute starting values would be more reproducible than other indices. comparative test-retest procedure (1 to 13 days between tests). institutional practice, ambulatory care. 15 subjects with stage 2 claudication. tcpO2 recordings at rest and at exercise during the 2 treadmill tests. calculation of the Delta-from-rest of oxygen pressure index (limb tcpO2 changes minus chest tcpO2 changes), of the resting - or minimal values attained during exercise - of absolute tcpO2 and of the regional perfusion index (regional perfusion index: ration of limb to chest). Both absolute tcpO2 and regional perfusion index at rest showed low reproducibility. During exercise the best reproducibility was attained through Delta-from-rest of oxygen pressure index calculation. Equations from the linear regression analysis (test 2 versus test 1) were 0.88 x -4.2 (r(2)=0.82) at the buttock level and 0.82 x -3.8 (r(2)=0.80) at the calf level. TcpO2 measurement on the calf or buttock during exercise, is a reproducible measurement in patients with vascular claudication, specifically when corrected for exercise-induced systemic pO2 changes trough Delta-from-rest of oxygen pressure calculation.

Reproducibility of an aerobic endurance test for nonexpert swimmers

Directory of Open Access Journals (Sweden)

Veronese da Costa A

2012-09-01

Full Text Available Adalberto Veronese da Costa,1,2 Manoel da Cunha Costa,3 Daniel Medeiros Carlos,1 Luis Marcos de Medeiros Guerra,1,2 Antônio José Silva,2 Tiago Manoel Cabral dos Santos Barbosa2,41Department of Physical Education, Bioscience Laboratory of Human Kinetics, Rio Grande do Norte State University, Mossoró, Brazil; 2Sport Sciences Trás-os-Montes e Alto Douro University, Research Center in Sport, Health and Human Development, Vila Real, Portugal; 3Superior School of Physical Education, Human Performance Laboratory, Pernambuco State University, Recife, Brazil; 4National Institute of Education, Nanyang Technological University, SingaporeBackground: This study aimed to verify the reproduction of an aerobic test to determine nonexpert swimmers' resistance.Methods: The sample consisted of 24 male swimmers (age: 22.79 ± 3.90 years; weight: 74.72 ± 11.44 kg; height: 172.58 ± 4.99 cm; and fat percentage: 15.19% ± 3.21%, who swim for 1 hour three times a week. A new instrument was used in this study (a Progressive Swim Test: the swimmer wore an underwater MP3 player and increased their swimming speed on hearing a beep after every 25 meters. Each swimmer's heart rate was recorded before the test (BHR and again after the test (AHR. The rate of perceived exertion (RPE and the number of laps performed (NLP were also recorded. The sample size was estimated using G*Power software (v 3.0.10; Franz Faul, Kiel University, Kiel, Germany. The descriptive values were expressed as mean and standard deviation. After confirming the normality of the data using both the Shapiro–Wilk and Levene tests, a paired t-test was performed to compare the data. The Pearson's linear correlation (r and intraclass coefficient correlation (ICC tests were used to determine relative reproducibility. The standard error of measurement (SEM and the coefficient of variation (CV were used to determine absolute reproducibility. The limits of agreement and the bias of the absolute and relative

Test-retest reliability of a questionnaire to assess physical environmental factors pertaining to physical activity

Directory of Open Access Journals (Sweden)

McGinn Aileen P

2005-06-01

Full Text Available Abstract Background Despite the documented benefits of physical activity, many adults do not obtain the recommended amounts. Barriers to physical activity occur at multiple levels, including at the individual, interpersonal, and environmental levels. Only until more recently has there been a concerted focus on how the physical environment might affect physical activity behavior. With this new area of study, self-report measures should be psychometrically tested before use in research studies. Therefore the objective of this study was to document the test-retest reliability of a questionnaire designed to assess physical environmental factors that might be associated with physical activity in a diverse adult population. Methods Test and retest surveys were conducted over the telephone with 106 African American and White women and men living in either Forsyth County, North Carolina or Jackson, Mississippi. Reliability of self-reported environmental factors across four domains (e.g., access to facilities and destinations, functionality and safety, aesthetics, natural environment was determined using intraclass correlation coefficients (ICC overall and separately by gender and race. Results Generally items displayed moderate and sometimes substantial reliability (ICC between 0.4 to 0.8, with a few differences by gender or race, across each of the domains. Conclusion This study provides some psychometric evidence for the use of many of these questions in studies examining the effect of self-reported physical environmental measures on physical activity behaviors, among African American and White women and men.

Stability of person ability measures in people with acquired brain injury in the use of everyday technology: the test-retest reliability of the Management of Everyday Technology Assessment (META).

Science.gov (United States)

Malinowsky, Camilla; Kassberg, Ann-Charlotte; Larsson-Lund, Maria; Kottorp, Anders

2016-01-01

To evaluate the test-retest reliability of the Management of Everyday Technology Assessment (META) in a sample of people with acquired brain injury (ABI). The META was administered twice within a two-week period to 25 people with ABI. A Rasch measurement model was used to convert the META ordinal raw scores into equal-interval linear measures of each participant's ability to manage everyday technology (ET). Test-retest reliability of the stability of the person ability measures in the META was examined by a standardized difference Z-test and an intra-class correlations analysis (ICC 1). The results showed that the paired person ability measures generated from the META were stable over the test-retest period for 22 of the 25 subjects. The ICC 1 correlation was 0.63, which indicates good overall reliability. The META demonstrated acceptable test-retest reliability in a sample of people with ABI. The results illustrate the importance of using sufficiently challenging ETs (relative to a person's abilities) to generate stable META measurements over time. Implications for Rehabilitation The findings add evidence regarding the test-retest reliability of the person ability measures generated from the observation assessment META in a sample of people with ABI. The META might support professionals in the evaluation of interventions that are designed to improve clients' performance of activities including the ability to manage ET.

Test-retest reliability, smallest real difference and concurrent validity of six different balance tests on young people with mild to moderate intellectual disability.

Science.gov (United States)

Blomqvist, Sven; Wester, Anita; Sundelin, Gunnevi; Rehn, Börje

2012-12-01

Some studies have reported that people with intellectual disability may have reduced balance ability compared with the population in general. However, none of these studies involved adolescents, and the reliability and validity of balance tests in this population are not known. The purpose of this study was to examine the reliability of six different balance tests and to investigate their concurrent validity. Test-retest reliability assessment. All subjects were recruited from a special school for people with intellectual disability in Bollnäs, Sweden. Eighty-nine adolescents (35 females and 54 males) with mild to moderate intellectual disability with a mean age of 18 years (range 16 to 20 years). All subjects followed the same test protocol on two occasions within an 11-day period. Balance test performances. Intraclass correlation coefficients greater than 0.80 were achieved for four of the balance tests: Extended Timed Up and Go Test, Modified Functional Reach Test, One-leg Stance Test and Force Platform Test. The smallest real differences ranged from 12% to 40%; less than 20% is considered to be low. Concurrent validity among these balance tests varied between no and low correlation. The results indicate that these tests could be used to evaluate changes in balance ability over time in people with mild to moderate intellectual disability. The low concurrent validity illustrates the importance of knowing more about the influence of various sensory subsystems that are significant for balance among adolescents with intellectual disability. Copyright © 2011 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Reproducibility problems of in-service ultrasonic testing results

International Nuclear Information System (INIS)

Honcu, E.

1974-01-01

The reproducibility of the results of ultrasonic testing is the basic precondition for its successful application in in-service inspection of changes in the quality of components of nuclear power installations. The results of periodic ultrasonic inspections are not satisfactory from the point of view of reproducibility. Regardless, the ultrasonic pulse-type method is suitable for evaluating the quality of most components of nuclear installations and often the sole method which may be recommended for inspection with regard to its technical and economic aspects. (J.B.)

The synthesis of no-carrier-added [11C]urea from [11C]carbon dioxide and application to [11C]uracil synthesis

International Nuclear Information System (INIS)

Chakraborty, P.K.; Mangner, T.J.; Chugani, H.T.

1997-01-01

No-carrier-added [ 11 C]urea has been synthesized by bubbling cyclotron-produced [ 11 C]-carbon dioxide directly into a tetrahydrofuran solution of lithium bis(trimethylsilyl)amide, followed by hydrolysis of the C-11 labeled adduct with aqueous ammonium chloride. Using this simple, one-pot method, [ 11 C]urea was produced in 55-70% radiochemical yield (decay-corrected) in 16 min following end-of-bombardment (or in 10 min following the introduction of the [ 11 C]carbon dioxide. The [ 11 C]urea thus produced was converted to [ 11 C]uracil (carrier-added) in 40-75% decay-corrected radiochemical yield by condensation with diethyl malate in presence of fuming sulfuric acid. (author)

The test-retest reliability of anatomical co-ordinate axes definition for the quantification of lower extremity kinematics during running.

Science.gov (United States)

Sinclair, Jonathan; Taylor, Paul John; Greenhalgh, Andrew; Edmundson, Christopher James; Brooks, Darrell; Hobbs, Sarah Jane

2012-12-01

Three-dimensional (3-D) kinematic analyses are used widely in both sport and clinical examinations. However, this procedure depends on reliable palpation of anatomical landmarks and mal-positioning of markers between sessions may result in improperly defined segment co-ordinate system axes which will produce in-consistent joint rotations. This had led some to question the efficacy of this technique. The aim of the current investigation was to assess the reliability of the anatomical frame definition when quantifying 3-D kinematics of the lower extremities during running. Ten participants completed five successful running trials at 4.0 m·s(-1) ± 5%. 3-D angular joint kinematics parameters from the hip, knee and ankle were collected using an eight camera motion analysis system. Two static calibration trials were captured. The first (test) was conducted prior to the running trials following which anatomical landmarks were removed. The second was obtained following completion of the running trials where anatomical landmarks were re-positioned (retest). Paired samples t-tests were used to compare 3-D kinematic parameters quantified using the two static trials, and intraclass correlations were employed to examine the similarities between the sagittal, coronal and transverse plane waveforms. The results indicate that no significant (p>0.05) differences were found between test and retest 3-D kinematic parameters and strong (R(2)≥0.87) correlations were observed between test and retest waveforms. Based on the results obtained from this investigation, it appears that the anatomical co-ordinate axes of the lower extremities can be defined reliably thus confirming the efficacy of studies using this technique.

Test-retest reliability and factor structures of organizational citizenship behavior for Hong Kong workers.

Science.gov (United States)

Lam, S S

2001-02-01

In 1990 Podsakoff, MacKenzie, Moorman, and Fetter developed a scale to measure the five dimensions of organizational citizenship behavior. Test-retest data over 15 weeks are reported for this scale for a sample of 82 female and 32 male Chinese tellers (ages 18 to 54 years) from a large international bank in Hong Kong. Stability was .83, and there was no significant change between Times 1 and 2. Analysis indicated the five-factor structure and showed it to be a reliable measure when used with a nonwestern sample.

Test-retest reliability and construct validity of the DOiT (Dutch Obesity Intervention in Teenagers) questionnaire: measuring energy balance-related behaviours in Dutch adolescents.

Science.gov (United States)

Janssen, Evelien H C; Singh, Amika S; van Nassau, Femke; Brug, Johannes; van Mechelen, Willem; Chinapaw, Mai J M

2014-02-01

Adequate assessment of energy balance-related behaviours in adolescents is essential to develop and evaluate effective obesity prevention programmes. The present study examined the test-retest reliability and construct validity of a questionnaire assessing energy balance-related behaviours in adolescents during the evaluation of the DOiT (Dutch Obesity Intervention in Teenagers) intervention. To assess test-retest reliability, adolescents filled in the questionnaire twice (n 111). To assess construct validity, the results from the first test were compared with data collected in a personal cognitive interview (n 20, independent from the reliability study). For both reliability and validity, intraclass correlation coefficients for continuous data or Cohen's kappa coefficients for categorical data were calculated as well as percentage agreement. Data were collected during school time from February to May 2010. Study participants were Dutch adolescents aged 12-14 years attending pre-vocational secondary schools. In more than three-quarters of the ninety-five questionnaire items the test-retest reliability appeared to be good to excellent. Moderate reliability was found for all other twenty-one items. Fifty-one items (of ninety-five items) showed good to excellent construct validity. Construct validity appeared moderate in twenty-three items and poor in twenty-one items. Most items with poor construct validity concerned consumption of sugar-containing beverages and high-energy snacks/sweets. Our study showed good test-retest reliability and largely moderate to good construct validity for the majority of items of the DOiT questionnaire. Items with poor construct validity (most of them found for items concerning energy intake-related behaviours) should be revised and tested again to improve the questionnaire for future use.

Test-retest measurements of dopamine D_1-type receptors using simultaneous PET/MRI imaging

International Nuclear Information System (INIS)

Kaller, Simon; Patt, Marianne; Becker, Georg-Alexander; Luthardt, Julia; Meyer, Philipp M.; Werner, Peter; Barthel, Henryk; Bresch, Anke; Sabri, Osama; Rullmann, Michael; Girbardt, Johanna; Fritz, Thomas H.; Hesse, Swen

2017-01-01

The role of dopamine D_1-type receptor (D_1R)-expressing neurons in the regulation of motivated behavior and reward prediction has not yet been fully established. As a prerequisite for future research assessing D_1-mediated neuronal network regulation using simultaneous PET/MRI and D_1R-selective ["1"1C]SCH23390, this study investigated the stability of central D_1R measurements between two independent PET/MRI sessions under baseline conditions. Thirteen healthy volunteers (7 female, age 33 ± 13 yrs) underwent 90-min emission scans, each after 90-s bolus injection of 486 ± 16 MBq ["1"1C]SCH23390, on two separate days within 2-4 weeks using a PET/MRI system. Parametric images of D_1R distribution volume ratio (DVR) and binding potential (BP_N_D) were generated by a multi-linear reference tissue model with two parameters and the cerebellar cortex as receptor-free reference region. Volume-of-interest (VOI) analysis was performed with manual VOIs drawn on consecutive transverse MRI slices for brain regions with high and low D_1R density. The DVR varied from 2.5 ± 0.3 to 2.9 ± 0.5 in regions with high D_1R density (e.g. the head of the caudate) and from 1.2 ± 0.1 to 1.6 ± 0.2 in regions with low D_1R density (e.g. the prefrontal cortex). The absolute variability of the DVR ranged from 2.4% ± 1.3% to 5.1% ± 5.3%, while Bland-Altman analyses revealed very low differences in mean DVR (e.g. 0.013 ± 0.17 for the nucleus accumbens). Intraclass correlation (one-way, random) indicated very high agreement (0.93 in average) for both DVR and BP_N_D values. Accordingly, the absolute variability of BP_N_D ranged from 7.0% ± 4.7% to 12.5% ± 10.6%; however, there were regions with very low D_1R content, such as the occipital cortex, with higher mean variability. The test-retest reliability of D_1R measurements in this study was very high. This was the case not only for D_1R-rich brain areas, but also for regions with low D_1R density. These results will provide a solid base

Assessing Cognitive Performance in Badminton Players: A Reproducibility and Validity Study

Directory of Open Access Journals (Sweden)

van de Water Tanja

2017-01-01

Full Text Available Fast reaction and good inhibitory control are associated with elite sports performance. To evaluate the reproducibility and validity of a newly developed Badminton Reaction Inhibition Test (BRIT, fifteen elite (25 ± 4 years and nine non-elite (24 ± 4 years Dutch male badminton players participated in the study. The BRIT measured four components: domain-general reaction time, badminton-specific reaction time, domain-general inhibitory control and badminton-specific inhibitory control. Five participants were retested within three weeks on the badminton-specific components. Reproducibility was acceptable for badminton-specific reaction time (ICC = 0.626, CV = 6% and for badminton-specific inhibitory control (ICC = 0.317, CV = 13%. Good construct validity was shown for badminton-specific reaction time discriminating between elite and non-elite players (F = 6.650, p 0.05. Concurrent validity for domain-general reaction time was good, as it was associated with a national ranking for elite (p = 0.70, p 0.05. In conclusion, reproducibility and validity of inhibitory control assessment was not confirmed, however, the BRIT appears a reproducible and valid measure of reaction time in badminton players. Reaction time measured with the BRIT may provide input for training programs aiming to improve badminton players’ performance.

Assessing Cognitive Performance in Badminton Players: A Reproducibility and Validity Study.

Science.gov (United States)

van de Water, Tanja; Huijgen, Barbara; Faber, Irene; Elferink-Gemser, Marije

2017-01-01

Fast reaction and good inhibitory control are associated with elite sports performance. To evaluate the reproducibility and validity of a newly developed Badminton Reaction Inhibition Test (BRIT), fifteen elite (25 ± 4 years) and nine non-elite (24 ± 4 years) Dutch male badminton players participated in the study. The BRIT measured four components: domain-general reaction time, badminton-specific reaction time, domain-general inhibitory control and badminton-specific inhibitory control. Five participants were retested within three weeks on the badminton-specific components. Reproducibility was acceptable for badminton-specific reaction time (ICC = 0.626, CV = 6%) and for badminton-specific inhibitory control (ICC = 0.317, CV = 13%). Good construct validity was shown for badminton-specific reaction time discriminating between elite and non-elite players (F = 6.650, p 0.05). Concurrent validity for domain-general reaction time was good, as it was associated with a national ranking for elite (p = 0.70, p badminton-specific reaction time, nor both components of inhibitory control (p > 0.05). In conclusion, reproducibility and validity of inhibitory control assessment was not confirmed, however, the BRIT appears a reproducible and valid measure of reaction time in badminton players. Reaction time measured with the BRIT may provide input for training programs aiming to improve badminton players' performance.

Test-retest reliability of the diagnosis of schizoaffective disorder in childhood and adolescence - A systematic review and meta-analysis.

Science.gov (United States)

Salamon, Sarah; Santelmann, Hanno; Franklin, Jeremy; Baethge, Christopher

2018-04-01

Reliability of schizoaffective disorder (SAD) diagnoses is low in adults but unclear in children and adolescents (CAD). We estimate the test-retest reliability of SAD and its key differential diagnoses (schizophrenia, bipolar disorder, and unipolar depression). Systematic literature search of Medline, Embase, and PsycInfo for studies on test-retest reliability of SAD, in CAD. Cohen's kappa was extracted from studies. We performed meta-analysis for kappa, including subgroup and sensitivity analysis (PROSPERO protocol: CRD42013006713). Out of > 4000 records screened, seven studies were included. We estimated kappa values of 0.27 [95%-CI: 0.07 0.47] for SAD, 0.56 [0.29; 0.83] for schizophrenia, 0.64 [0.55; 0.74] for bipolar disorder, and 0.66 [0.52; 0.81] for unipolar depression. In 5/7 studies kappa of SAD was lower than that of schizophrenia; similar trends emerged for bipolar disorder (4/5) and unipolar depression (2/3). Estimates of positive agreement of SAD diagnoses supported these results. The number of studies and patients included is low. The point-estimate of the test-retest reliability of schizoaffective disorder is only fair, and lower than that of its main differential diagnoses. All kappa values under study were lower in children and adolescents samples than those reported for adults. Clinically, schizoaffective disorder should be diagnosed in strict adherence to the operationalized criteria and ought to be re-evaluated regularly. Should larger studies confirm the insufficient reliability of schizoaffective disorder in children and adolescents, the clinical value of the diagnosis is highly doubtful. Copyright © 2017. Published by Elsevier B.V.

Test-Retest Reliability of fMRI During Nonverbal Semantic Decisions in Moderate-Severe Nonfluent Aphasia Patients

Directory of Open Access Journals (Sweden)

Jacquie Kurland

2004-01-01

Full Text Available Cortical reorganization in poststroke aphasia is not well understood. Few studies have investigated neural mechanisms underlying language recovery in severe aphasia patients, who are typically viewed as having a poor prognosis for language recovery. Although test-retest reliability is routinely demonstrated during collection of language data in single-subject aphasia research, this is rarely examined in fMRI studies investigating the underlying neural mechanisms in aphasia recovery.

Towards Reproducibility in Computational Hydrology

Science.gov (United States)

Hutton, Christopher; Wagener, Thorsten; Freer, Jim; Han, Dawei; Duffy, Chris; Arheimer, Berit

2017-04-01

the example application area, we believe that our conclusions are of value to the wider environmental and geoscience community as far as the use of code and models for scientific advancement is concerned. References: [1] Hutton, C., T. Wagener, J. Freer, D. Han, C. Duffy, and B. Arheimer (2016), Most computational hydrology is not reproducible, so is it really science?, Water Resour. Res., 52, 7548-7555, doi:10.1002/2016WR019285. [2] Ceola, S., et al. (2015), Virtual laboratories: New opportunities for collaborative water science, Hydrol. Earth Syst. Sci. Discuss., 11(12), 13443-13478, doi:10.5194/hessd-11-13443-2014.

Reproducibility and validity of the DynaPort KneeTest

NARCIS (Netherlands)

Mokkink, L.B.; Terwee, C.B.; Slikke, van der R.M.; Lummel, van R.C.; Benink, R.J.; Bouter, L.M.; Vet, de H.C.W.

2005-01-01

OBJECTIVE: To determine the reproducibility and validity of the DynaPort KneeTest, a performance-based test that measures quality of movement of patients undergoing total knee replacement (TKR). METHODS: A total of 92 patients with osteoarthritis (OA) of the knee performed the KneeTest twice on the

Opioid receptor imaging and displacement studies with [6-O-[{sup 11}C]methyl]buprenorphine in baboon brain

Energy Technology Data Exchange (ETDEWEB)

Galynker, Igor; Schlyer, David J.; Dewey, Stephen L.; Fowler, Joanna S.; Logan, Jean; Gatley, S. John; MacGregor, Robert R.; Ferrieri, Richard A.; Holland, M. J.; Brodie, Jonathan; Simon, Eric; Wolf, Alfred P

1996-04-01

Buprenorphine (BPN) is a mixed opiate agonist-antagonist used as an analgesic and in the treatment of opiate addiction. We have used [6-O-[{sup 11}C]methyl]buprenorphine ([{sup 11}C]BPN) to measure the regional distribution in baboon brain, the test-retest stability of repeated studies in the same animal, the displacement of the labeled drug by naloxone in vivo, and the tissue distribution in mice. The regional distribution of radioactivity in baboon brain determined with PET was striatum > thalamus > cingulate gyrus > frontal cortex > parietal cortex > occipital cortex > cerebellum. This distribution corresponded to opiate receptor density and to previously published data (37). The tracer uptake in adult female baboons showed no significant variation in serial scans in the same baboon with no intervention in the same scanning session. HPLC analysis of baboon plasma showed the presence of labeled metabolites with 92% {+-} 2.2% and 43% {+-} 14.4% of the intact tracer remaining at 5 and 30 min, respectively. Naloxone, an opiate receptor antagonist, administered 30-40 min after tracer injection at a dose of 1.0 mg/kg i.v., reduced [{sup 11}C]BPN binding in thalamus, striatum, cingulate gyrus, and frontal cortex to values 0.25 to 0.60 of that with no intervention. There were minimal (< 15%) effects on cerebellum. Naloxone treatment significantly reduced the slope of the Patlak plot in receptor-containing regions. These results demonstrate that [{sup 11}C]BPN can be displaced by naloxone in vivo, and they affirm the feasibility of using this tracer and displacement methodology for short-term kinetics studies with PET. Mouse tissue distribution data were used to estimate the radiation dosimetry to humans. The critical organ was the small intestine, with a radiation dose estimate to humans of 117 nrad/mCi.

Test-retest reliability of spatial and temporal gait parameters in children with cerebral palsy as measured by an electronic walkway.

Science.gov (United States)

Sorsdahl, Anne Brit; Moe-Nilssen, Rolf; Strand, Liv Inger

2008-01-01

The purpose of this study was to examine test-retest reliability of seven selected temporal and spatial gait parameters and asymmetry measures in children with cerebral palsy. Seventeen children with CP between 3 and 13 years of age walked at three different speeds across an electronic walkway of 5.2m. The tests were repeated after approximately 25 min. The scores were normalized to a walking speed of 1.1m/s to avoid the confounding effect of gait speed on speed dependent gait parameters. Intraclass correlation coefficients (ICC(1,1) and ICC(3,1)) with 95% confidence intervals, within-subject standard deviation (S(w)) and smallest detectable difference (SDD) were calculated. The relative reliability of cadence, step length, stride length and single stance time was high to excellent (ICC(1,1) between 0.73 and 0.95), while it was poor for step width (ICC(1,1)=0.27 and 0.35). The relative reliability for two calculated asymmetry measures were high for the step length index (ICC(1,1)=0.82) and moderate for the single stance time index (ICC(1,1)=0.49). The absolute reliability values for all gait parameters are reported. Five of seven gait parameters measured by an electronic walkway and normalized to a common walking speed, appear to be highly repeatable in a short-term time span in children with CP who were able to walk without assistive walking devices, provided sufficient cognitive function.

Pad-weighing test performed with standardized bladder volume

DEFF Research Database (Denmark)

Lose, G; Rosenkilde, P; Gammelgaard, J

1988-01-01

The result of the one-hour pad-weighing test proposed by the International Continence Society has been demonstrated to depend on the urine load during the test. To increase reproducibility of the pad-weighing test by minimizing the influence of variation in urine load the test was done with a sta...... to +/- 24 g between two tests. It is concluded that this setup (i.e., standardized bladder volume) of the one-hour pad-weighing test allows for a more reliable assessment of urinary incontinence for quantitative purposes....... with a standardized bladder volume (50% of the cystometric bladder capacity). Twenty-five female patients with stress or mixed incontinence underwent two separate tests. Test-retest results were highly correlated (r = 0.97, p less than 0.001). Nonetheless, analysis of test-retest differences revealed a variation up...

Synthesis of [(11)C]Am80 via Novel Pd(0)-Mediated Rapid [(11)C]Carbonylation Using Arylboronate and [(11)C]Carbon Monoxide.

Science.gov (United States)

Takashima-Hirano, Misato; Ishii, Hideki; Suzuki, Masaaki

2012-10-11

(11)C-labeled methylbenzoates [(11)C]4a-d were synthesized using Pd(0)-mediated rapid cross-coupling reactions employing [(11)C]carbon monoxide and arylboronic acid neopentyl glycol esters 3a-d under atmospheric pressure in methanol-dimethylformamide (MeOH-DMF), in radiochemical yields of 12 ± 5-26 ± 13% (decay-corrected based on [(11)C]O). The reaction conditions were highly favorable for the synthesis of [(11)C]Am80 ([(11)C]2) and [(11)C]methyl 4-((5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)carbamoyl)benzoate ([(11)C]2-Me) using 4-(5,5-dimethyl-1,3,2-dioxaborinan-2-yl)-N-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)benzamide (5), both of which produced a decay-corrected radiochemical yield (RCY) of 26 ± 13%, with >99% radiochemical purity and an average specific radioactivity of 44 GBq/μmol. The yields of [(11)C]4a, [(11)C]2-Me, and [(11)C]2 were improved by the use of a 2-fold excess of the solvents and reagents under the same conditions to give respective yields of 66 ± 8, 65 ± 7, and 48 ± 2%.

{sup 11}C-ORM-13070, a novel PET ligand for brain α{sub 2C}-adrenoceptors: radiometabolism, plasma pharmacokinetics, whole-body distribution and radiation dosimetry in healthy men

Energy Technology Data Exchange (ETDEWEB)

Luoto, Pauliina; Oikonen, Vesa; Arponen, Eveliina; Helin, Semi; Virta, Jere; Virtanen, Kirsi; Roivainen, Anne [University of Turku and Turku University Hospital, Turku PET Centre, Turku (Finland); Suilamo, Sami [University of Turku and Turku University Hospital, Turku PET Centre, Turku (Finland); Turku University Hospital, Department of Oncology and Radiotherapy, Turku (Finland); Herttuainen, Jukka; Hietamaeki, Johanna; Holopainen, Aila; Rouru, Juha; Sallinen, Jukka [Orion Pharma, Espoo and Turku (Finland); Kailajaervi, Marita [GE Healthcare, Turku Imanet, Turku (Finland); Peltonen, Juha M.; Scheinin, Mika; Volanen, Iina [University of Turku, CRST, Turku (Finland); Rinne, Juha O. [University of Turku and Turku University Hospital, Turku PET Centre, Turku (Finland); University of Turku, CRST, Turku (Finland); TYKSLAB, Unit of Clinical Pharmacology, Turku (Finland); University of Turku and Turku University Hospital, Division of Clinical Neurosciences, Turku (Finland)

2014-10-15

{sup 11}C-labelled 1-[(S)-1-(2,3-dihydrobenzo[1,2]dioxin-2-yl)methyl] -4-(3-methoxy-methylpyridin-2- yl)-piperazine ({sup 11}C-ORM-13070) is a novel PET tracer for imaging of α{sub 2C}-adrenoceptors in the human brain. Brain α{sub 2C}-adrenoceptors may be therapeutic targets in several neuropsychiatric disorders, including depression, schizophrenia and Alzheimer's disease. To validate the use of {sup 11}C-ORM-13070 in humans, we investigated its radiometabolism, pharmacokinetics, whole-body distribution and radiation dose. Radiometabolism was studied in a test-retest setting in six healthy men. After intravenous injection of {sup 11}C-ORM-13070, blood samples were drawn over 60 min. Plasma samples were analysed by radio-HPLC for intact tracer and its radioactive metabolites. Metabolite-corrected plasma time-activity curves were used for calculation of pharmacokinetics. In a separate group of 12 healthy men, the whole-body distribution of {sup 11}C-ORM-13070 and radiation exposure were investigated by dynamic PET/CT imaging without blood sampling. Two radioactive metabolites of {sup 11}C-ORM-13070 were detected in human arterial plasma. The proportion of unchanged {sup 11}C-ORM-13070 decreased from 81 ± 4 % of total radioactivity at 4 min after tracer injection to 23 ± 4 % at 60 min. At least one of the radioactive metabolites penetrated into red blood cells, while the parent tracer remained in plasma. The apparent elimination rate constant and corresponding half-life of unchanged {sup 11}C-ORM-13070 in arterial plasma were 0.0117 ± 0.0056 min{sup -1} and 73.6 ± 35.8 min, respectively. The organs with the highest absorbed doses were the liver (12 μSv/MBq), gallbladder wall (12 μSv/MBq) and pancreas (9.1 μSv/MBq). The mean effective dose was 3.9 μSv/MBq, with a range of 3.6 - 4.2 μSv/MBq. {sup 11}C-ORM-13070 was rapidly metabolized in human subjects after intravenous injection. The effective radiation dose of {sup 11}C-ORM-13070 was in the same range

Reproducibility and validity of the Nintendo Wii Balance Board for measuring shoulder sensorimotor control in prone lying

DEFF Research Database (Denmark)

Eshøj, Henrik; Juul-Kristensen, Birgit; Gam Bender Jørgensen, René

2017-01-01

INTRODUCTION: For the lower limbs, the Nintendo Wii Balance Board (NWBB) has been widely used to measure postural control. However, this has not been performed for upper limb measurements. Further, the NWBB has shown to produce more background noise with decreasing loads, which may be of concern...... when used for upper limb testing. The aim was to investigate reproducibility and validity of the NWBB. METHODS: A test-retest design was performed with 68 subjects completing three different prone lying, upper limb weight-bearing balance tasks on a NWBB: two-arms, eyes closed (1) one-arm, non...

Test-retest assessment of cortical activation induced by repetitive transcranial magnetic stimulation with brain atlas-guided optical topography

Science.gov (United States)

Tian, Fenghua; Kozel, F. Andrew; Yennu, Amarnath; Croarkin, Paul E.; McClintock, Shawn M.; Mapes, Kimberly S.; Husain, Mustafa M.; Liu, Hanli

2012-11-01

Repetitive transcranial magnetic stimulation (rTMS) is a technology that stimulates neurons with rapidly changing magnetic pulses with demonstrated therapeutic applications for various neuropsychiatric disorders. Functional near-infrared spectroscopy (fNIRS) is a suitable tool to assess rTMS-evoked brain responses without interference from the magnetic or electric fields generated by the TMS coil. We have previously reported a channel-wise study of combined rTMS/fNIRS on the motor and prefrontal cortices, showing a robust decrease of oxygenated hemoglobin concentration (Δ[HbO2]) at the sites of 1-Hz rTMS and the contralateral brain regions. However, the reliability of this putative clinical tool is unknown. In this study, we develop a rapid optical topography approach to spatially characterize the rTMS-evoked hemodynamic responses on a standard brain atlas. A hemispherical approximation of the brain is employed to convert the three-dimensional topography on the complex brain surface to a two-dimensional topography in the spherical coordinate system. The test-retest reliability of the combined rTMS/fNIRS is assessed using repeated measurements performed two to three days apart. The results demonstrate that the Δ[HbO2] amplitudes have moderate-to-high reliability at the group level; and the spatial patterns of the topographic images have high reproducibility in size and a moderate degree of overlap at the individual level.

Test-retest variability of multifocal electroretinography in normal volunteers and short-term variability in hydroxychloroquine users

Directory of Open Access Journals (Sweden)

Browning DJ

2014-08-01

Full Text Available David J Browning,1 Chong Lee2 1Charlotte Eye, Ear, Nose and Throat Associates, 2University of North Carolina – Charlotte, Charlotte, NC, USA Purpose: To determine measurement variability of N1P1 amplitudes and the R1/R2 ratio in normal subjects and hydroxychloroquine users without retinopathy. Design: Retrospective, observational study. Subjects: Normal subjects (n=21 and 44 patients taking hydroxychloroquine (n=44 without retinopathy. Methods: Multifocal electroretinography (mfERG was performed twice in one session in the 21 normal subjects and twice within 1 year in the hydroxychloroquine users, during which time no clinical change in macular status occurred. Main outcome measures: N1P1 amplitudes of rings R1–R5, the R1/R2 ratio, and coefficients of repeatability (COR for these measurements. Results: Values for N1P1 amplitudes in hydroxychloroquine users were reduced compared with normal subjects by the known effect of age, but R1/R2 was not affected by age. The COR for R1–R5 ranged from 43% to 52% for normal subjects and from 43% to 59% for hydroxychloroquine users; for R1/R2 the COR was 29% in normal subjects and 45% in hydroxychloroquine users. Conclusion: mfERG measurements show high test-retest variability, limiting the ability of a single mfERG test to influence a decision to stop hydroxychloroquine; corroborative evidence with a different ancillary test is recommended in a suspicious case. Keywords: multifocal electroretinography, hydroxychloroquine, test-retest variability 

Self-transcendence trait and its relationship with in vivo serotonin transporter availability in brainstem raphe nuclei: An ultra-high resolution PET-MRI study.

Science.gov (United States)

Kim, Jong-Hoon; Son, Young-Don; Kim, Jeong-Hee; Choi, Eun-Jung; Lee, Sang-Yoon; Joo, Yo-Han; Kim, Young-Bo; Cho, Zang-Hee

2015-12-10

Self-transcendence is an inherent human personality trait relating to the experience of spiritual aspects of the self. We examined the relationship between self-transcendence and serotonin transporter (SERT) availability in brainstem raphe nuclei, which are collections of five different serotonergic nuclei with rostro-caudal extension, using ultra-high resolution magnetic resonance imaging (MRI) and positron emission tomography (PET) with (11)C-3-amino-4-(2-dimethylaminomethylphenylthio)benzonitrile ([(11)C]DASB) to elucidate potential roles of serotonergic neuronal activities in this personality trait. Sixteen healthy subjects completed 7.0T MRI and High Resolution Research Tomograph (HRRT) PET. The regions of interest (ROIs) included the dorsal raphe nucleus (R1), median raphe nucleus (R2), raphe pontis (R3), and the caudal raphe nuclei (R4 and R5). For the estimation of SERT availability, the binding potential (BPND) was derived using the simplified reference tissue model (SRTM2). The Temperament and Character Inventory was used to measure self-transcendence. The analysis revealed that the self-transcendence total score had a significant negative correlation with the [(11)C]DASB BPND in the caudal raphe (R5). The subscale score for spiritual acceptance was significantly negatively correlated with the [(11)C]DASB BPND in the median raphe nucleus (R2). The results indicate that the self-transcendence trait is associated with SERT availability in specific raphe subnuclei, suggesting that the serotonin system may serve as an important biological basis for human self-transcendence. Based on the connections of these nuclei with cortico-limbic and visceral autonomic structures, the functional activity of these nuclei and their related neural circuitry may play a crucial role in the manifestation of self-transcendence. Copyright © 2015. Published by Elsevier B.V.

Inter-Rater and Test-Retest (Between-Sessions) Reliability of the 4-Skills Scan for Dutch Elementary School Children

Science.gov (United States)

van Kernebeek, Willem G.; de Schipper, Antoine W.; Savelsbergh, Geert J. P.; Toussaint, Huub M.

2018-01-01

In The Netherlands, the 4-Skills Scan is an instrument for physical education teachers to assess gross motor skills of elementary school children. Little is known about its reliability. Therefore, in this study the test-retest and inter-rater reliability was determined. Respectively, 624 and 557 Dutch 6- to 12-year-old children were analyzed for…

A PET study of effects of chronic 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") on serotonin markers in Göttingen minipig brain

DEFF Research Database (Denmark)

Cumming, Paul; Møller, Mette; Benda, Kjeld

2007-01-01

The psychostimulant 3,4-methylendioxymethamphetamine (MDMA, "ecstasy") evokes degeneration of telencephalic serotonin innervations in rodents, nonhuman primates, and human recreational drug users. However, there has been no alternative to nonhuman primates for studies of the cognitive and neuroch......The psychostimulant 3,4-methylendioxymethamphetamine (MDMA, "ecstasy") evokes degeneration of telencephalic serotonin innervations in rodents, nonhuman primates, and human recreational drug users. However, there has been no alternative to nonhuman primates for studies of the cognitive...... with MDMA (i.m.), administered at a range of doses. In parallel PET studies, [(11)C]WAY-100635 was used to map the distribution of serotonin 5HT(1A) receptors. The acute MDMA treatment in awake pigs evoked 1 degrees C of hyperthermia. MDMA at total doses greater than 20 mg/kg administered over 2-4 days...... reduced the binding potential (pB) of [(11)C]DASB for serotonin transporters in porcine brain. A mean total dose of 42 mg/kg MDMA in four animals evoked a mean 32% decrease in [(11)C]DASB pB in mesencephalon and diencephalon, and a mean 53% decrease in telencephalic structures. However, this depletion...

A study of 11C-acetate production using 11C-choline commercial module

International Nuclear Information System (INIS)

Zhang Jinming; Tian Jiahe; Yao Shulin; Chen Yan

2008-01-01

Objective: 11 C-acetate is a useful PET tracer in evaluating myocardial metabolism but more interest has been focused on its application in tumor detection in recent years, especially hepatocellular carcinoma (HCC). This study was designed to evaluate the laboratory, preparation of 11 C-acetate with a modified 11 C-choline commercial module and to investigate its biodistribution in tumor (lung adenocarcinoma)-bearing mice as well as its potential as a tumor imaging agent. Methods: 11 C-acetate was synthesized with a modified 11 C choline module: Methyl magnesium bromide Grignard (0.1 ml of 1.5 mol/L) was load- ed to a Teflon loop before 11 CO 2 was recovered from the target. Cartier acetate solution (2 ml of 1 mmol/L) was pushed through the loop, SPE cartridges (mixed AG50 and IC-Ag) and then the QMA. The loop and cartridges were then rinsed with water. The product 11 C-acetate was then washed out from QMA with 0.9% NaCl solution into a collection vial containing diluted HCl. 11 C-carbonate was removed by nitrogen bubbling for 2 min. After neutralization with trisodium citrate, the injectable 11 C-acetate solution was obtained. The tumor-bearing mice were sacrificed. The percentage activity of injected dose per gram of tissue (% ID/g) for tumor and other tissues were calculated. One patient with known diagnosis of moderately differentiated HCC was injected with 11 C-acetate and imaged by PET/CT, followed by 18 F-fluorodeoxyglucose (FDG). Results: The synthesis yield of 11 C-acetate was (60.5 ± 8.7)% (decay conected, n=10); the radio-chemistry purity was > 98% and the synthesis time was 10 min from 11 CO 2 to 11 C-acetate. The radioactivity ratio for tumor/muscle was 1.76 at 30 min. A patient with known HCC showed positive 11 C-acetate accumulation in the tumor but was negative in 18 F-FDG. Conclusion: The synthesis of 11 C-acetate by modification of an 11 C-choline commercial module was feasible and it could be achieved with high yield, high radiochemical purity

14 CFR 63.59 - Retesting after failure.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Retesting after failure. 63.59 Section 63.59 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... failure. (a) An applicant for a flight navigator certificate who fails a written or practical test for...

The determination of unchanged [11C]diprenorphine, [11C]L-deprenyl and [11C]raclopride in plasma by HPLC

International Nuclear Information System (INIS)

Luthra, S.K.; Turton, D.R.; Price, G.; Ahier, R.; Martin, F.; Hume, S.; Cremer, J.

1990-01-01

In PET studies a knowledge of the fraction of radioactivity in plasma representing unchanged 11 C-labelled ligand/tracer is essential for correction of the arterial plasma input curve. A number of different approaches (e.g. HPLC and TLC/OPTLC) to the determination of unchanged radio-ligand/tracer have been reported for 11 C-labelled carfentanil, raclopride and L-deprenyl and for 76 Br-labelled bromolisuride. The authors report here how they have applied the simple work-up and analytical procedure, originally reported for [ 11 C]carfentanil, to establish the percentage of unmchanged 11 C-labelled diprenorphine, L-deprenyl and raclopride in human and animal plasma as a function of time

OECD validation study to assess intra- and inter-laboratory reproducibility of the zebrafish embryo toxicity test for acute aquatic toxicity testing.

Science.gov (United States)

Busquet, François; Strecker, Ruben; Rawlings, Jane M; Belanger, Scott E; Braunbeck, Thomas; Carr, Gregory J; Cenijn, Peter; Fochtman, Przemyslaw; Gourmelon, Anne; Hübler, Nicole; Kleensang, André; Knöbel, Melanie; Kussatz, Carola; Legler, Juliette; Lillicrap, Adam; Martínez-Jerónimo, Fernando; Polleichtner, Christian; Rzodeczko, Helena; Salinas, Edward; Schneider, Katharina E; Scholz, Stefan; van den Brandhof, Evert-Jan; van der Ven, Leo T M; Walter-Rohde, Susanne; Weigt, Stefan; Witters, Hilda; Halder, Marlies

2014-08-01

The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were analytically confirmed for 11 chemicals. Newly fertilised zebrafish eggs (20/concentration and control) were exposed for 96h to chemicals. Four apical endpoints were recorded daily as indicators of acute lethality: coagulation of the embryo, lack of somite formation, non-detachment of the tail bud from the yolk sac and lack of heartbeat. Results (LC50 values for 48/96h exposure) show that the ZFET is a robust method with a good intra- and inter-laboratory reproducibility (CV30%) for some very toxic or volatile chemicals, and chemicals tested close to their limit of solubility. The ZFET is now available as OECD Test Guideline 236. Considering the high predictive capacity of the ZFET demonstrated by Belanger et al. (2013) in their retrospective analysis of acute fish toxicity and fish embryo acute toxicity data, the ZFET is ready to be considered for acute fish toxicity for regulatory purposes. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Test-retest and interobserver reliability of quantitative sensory testing according to the protocol of the German Research Network on Neuropathic Pain (DFNS): a multi-centre study.

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Geber, Christian; Klein, Thomas; Azad, Shahnaz; Birklein, Frank; Gierthmühlen, Janne; Huge, Volker; Lauchart, Meike; Nitzsche, Dorothee; Stengel, Maike; Valet, Michael; Baron, Ralf; Maier, Christoph; Tölle, Thomas; Treede, Rolf-Detlef

2011-03-01

Quantitative sensory testing (QST) is an instrument to assess positive and negative sensory signs, helping to identify mechanisms underlying pathologic pain conditions. In this study, we evaluated the test-retest reliability (TR-R) and the interobserver reliability (IO-R) of QST in patients with sensory disturbances of different etiologies. In 4 centres, 60 patients (37 male and 23 female, 56.4±1.9years) with lesions or diseases of the somatosensory system were included. QST comprised 13 parameters including detection and pain thresholds for thermal and mechanical stimuli. QST was performed in the clinically most affected test area and a less or unaffected control area in a morning and an afternoon session on 2 consecutive days by examiner pairs (4 QSTs/patient). For both, TR-R and IO-R, there were high correlations (r=0.80-0.93) at the affected test area, except for wind-up ratio (TR-R: r=0.67; IO-R: r=0.56) and paradoxical heat sensations (TR-R: r=0.35; IO-R: r=0.44). Mean IO-R (r=0.83, 31% unexplained variance) was slightly lower than TR-R (r=0.86, 26% unexplained variance, Ptest area (TR-R: r=0.86; IO-R: r=0.83) than in the control area (TR-R: r=0.79; IO-R: r=0.71, each Preliability of QST. We conclude that standardized QST performed by trained examiners is a valuable diagnostic instrument with good test-retest and interobserver reliability within 2days. With standardized training, observer bias is much lower than random variance. Quantitative sensory testing performed by trained examiners is a valuable diagnostic instrument with good interobserver and test-retest reliability for use in patients with sensory disturbances of different etiologies to help identify mechanisms of neuropathic and non-neuropathic pain. Copyright © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Test-retest reliability and predictors of unreliable reporting for a sexual behavior questionnaire for U.S. men.

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Nyitray, Alan G; Harris, Robin B; Abalos, Andrew T; Nielson, Carrie M; Papenfuss, Mary; Giuliano, Anna R

2010-12-01

Accurate knowledge about human sexual behaviors is important for increasing our understanding of human sexuality; however, there have been few studies assessing the reliability of sexual behavior questionnaires designed for community samples of adult men. A test-retest reliability study was conducted on a questionnaire completed by 334 men who had been recruited in Tucson, Arizona. Reliability coefficients and refusal rates were calculated for 39 non-sexual and sexual behavior questionnaire items. Predictors of unreliable reporting for lifetime number of female sexual partners were also assessed. Refusal rates were generally low, with slightly higher refusal rates for questions related to immigration, income, the frequency of sexual intercourse with women, lifetime number of female sexual partners, and the lifetime number of male anal sex partners. Kappa and intraclass correlation coefficients were substantial or almost perfect for all non-sexual and sexual behavior items. Reliability dropped somewhat, but was still substantial, for items that asked about household income and the men's knowledge of their sexual partners' health, including abnormal Pap tests and prior sexually transmitted diseases (STD). Age and lifetime number of female sexual partners were independent predictors of unreliable reporting while years of education was inversely associated with unreliable reporting. These findings among a community sample of adult men are consistent with other test-retest reliability studies with populations of women and adolescents.

Activity in prelimbic cortex is required for adjusting the anxiety response level during the elevated plus-maze retest.

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Stern, C A J; Do Monte, F H M; Gazarini, L; Carobrez, A P; Bertoglio, L J

2010-09-29

The prelimbic (PL) subregion of medial prefrontal cortex has been implicated in anxiety regulation. It is unknown, however, whether PL cortex also serves to fine-tuning the level of anxiety-related behavior exhibited on the next exposure to the same potentially threatening situation. To address this, we infused cobalt (1.0 mM) to temporarily inactivate the PL cortex during testing, post-testing or retesting in the elevated plus-maze (EPM). This protocol was chosen because it allowed us to concurrently investigate anxiety and the process of aversive learning and memory. PL cortex inactivation during the EPM testing increased the exploration of open-arms, substantiating its role in anxiety. PL cortex inactivation during the EPM retesting counteracted the further avoidance to open-arms exhibited by rats. Interestingly, as evidenced by min-by-min analysis, the cobalt-treated group behaved on EPM retesting as did the vehicle-treated group on EPM testing. This result may imply that activity in PL cortex is necessary for retrieving previously learned information that adjusts the anxiety response level on EPM retesting. Alternatively, a simple reduction in anxiety could explain the cobalt-induced increase in retest open-arms exploration. Neither test nor post-test PL cortex inactivation affected the further avoidance to open-arms observed on EPM retesting. To extend the investigation of PL cortex role in the regulation of open-arms avoidance, we infused other drugs prior to testing or retesting in the EPM. Antagonism of PL cortex adrenergic beta-1 receptors with atenolol (10 nmol), cholinergic muscarinic receptors with scopolamine (20 nmol) or glutamatergic N-methyl-d-aspartic acid (NMDA) receptors with AP5 (6.0 nmol) interfered with the level of open-arms exploration on testing, but not on retesting. Copyright 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Design of Infusion Schemes for Neuroreceptor Imaging: Application to [11C]Flumazenil-PET Steady-State Study

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Ling Feng

2016-01-01

Full Text Available This study aims at developing a simulation system that predicts the optimal study design for attaining tracer steady-state conditions in brain and blood rapidly. Tracer kinetics was determined from bolus studies and used to construct the system. Subsequently, the system was used to design inputs for bolus infusion (BI or programmed infusion (PI experiments. Steady-state quantitative measurements can be made with one short scan and venous blood samples. The GABAA receptor ligand [C11]Flumazenil (FMZ was chosen for this purpose, as it lacks a suitable reference region. Methods. Five bolus [C11]FMZ-PET scans were conducted, based on which population-based PI and BI schemes were designed and tested in five additional healthy subjects. The design of a PI was assisted by an offline feedback controller. Results. The system could reproduce the measurements in blood and brain. With PI, [C11]FMZ steady state was attained within 40 min, which was 8 min earlier than the optimal BI (B/I ratio = 55 min. Conclusions. The system can design both BI and PI schemes to attain steady state rapidly. For example, subjects can be [C11]FMZ-PET scanned after 40 min of tracer infusion for 40 min with venous sampling and a straight-forward quantification. This simulation toolbox is available for other PET-tracers.

We need more replication research - A case for test-retest reliability.

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Leppink, Jimmie; Pérez-Fuster, Patricia

2017-06-01

Following debates in psychology on the importance of replication research, we have also started to see pleas for a more prominent role for replication research in medical education. To enable replication research, it is of paramount importance to carefully study the reliability of the instruments we use. Cronbach's alpha has been the most widely used estimator of reliability in the field of medical education, notably as some kind of quality label of test or questionnaire scores based on multiple items or of the reliability of assessment across exam stations. However, as this narrative review outlines, Cronbach's alpha or alternative reliability statistics may complement but not replace psychometric methods such as factor analysis. Moreover, multiple-item measurements should be preferred above single-item measurements, and when using single-item measurements, coefficients as Cronbach's alpha should not be interpreted as indicators of the reliability of a single item when that item is administered after fundamentally different activities, such as learning tasks that differ in content. Finally, if we want to follow up on recent pleas for more replication research, we have to start studying the test-retest reliability of the instruments we use.

Test-Retest Reliability and Minimal Detectable Change of Randomized Dichotic Digits in Learning-Disabled Children: Implications for Dichotic Listening Training.

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Mahdavi, Mohammad Ebrahim; Pourbakht, Akram; Parand, Akram; Jalaie, Shohreh

2018-03-01

Evaluation of dichotic listening to digits is a common part of many studies for diagnosis and managing auditory processing disorders in children. Previous researchers have verified test-retest relative reliability of dichotic digits results in normal children and adults. However, detecting intervention-related changes in the ear scores after dichotic listening training requires information regarding trial-to-trial typical variation of individual ear scores that is estimated using indices of absolute reliability. Previous studies have not addressed absolute reliability of dichotic listening results. To compare the results of the Persian randomized dichotic digits test (PRDDT) and its relative and absolute indices of reliability between typical achieving (TA) and learning-disabled (LD) children. A repeated measures observational study. Fifteen LD children were recruited from a previously performed study with age range of 7-12 yr. The control group consisted of 15 TA schoolchildren with age range of 8-11 yr. The Persian randomized dichotic digits test was administered on the children under free recall condition in two test sessions 7-12 days apart. We compared the average of the ear scores and ear advantage between TA and LD children. Relative indices of reliability included Pearson's correlation and intraclass correlation (ICC 2,1 ) coefficients and absolute reliability was evaluated by calculation of standard error of measurement (SEM) and minimal detectable change (MDC) using the raw ear scores. The Pearson correlation coefficient indicated that in both groups of children the ear scores of test and retest sessions were strongly and positively (greater than +0.8) correlated. The ear scores showed excellent ICC coefficient of consistency (0.78-0.82) and fair to excellent ICC coefficient of absolute agreement (0.62-0.74) in TA children and excellent ICC coefficients of consistency and absolute agreement in LD children (0.76-0.87). SEM and SEM% of the ear scores in TA

Enzymatic synthesis of 11C-pyruvic acid and 11C-L-lactic acid

International Nuclear Information System (INIS)

Cohen, M.B.; Spolter, L.; Chang, C.C.; Cook, J.S.; Macdonald, N.S.

1980-01-01

L-Lactic acid is formed as the end product of glycolysis under anaerobic conditions in all cells, but this reaction is of special significance in the myocardium. L-Lactic acid is reversibly formed from and is in equilibrium with myocardial pyruvic acid, which is its sole metabolic pathway. 11 C-Pyruvic acid is synthesized from 11 C carbon dioxide using pyruvate-ferredoxin oxidoreductase and coenzymes. The 11 C-pyruvic acid is then converted to 11 -L-lactic acid by lactic acid dehydrogenase. The availability of 11 C-pyruvic acid and 11 C-L-lactic acid will permit the in vivo investigation of lactate metabolism. (author)

Test-retest reliability of the Middlesex Assessment of Mental State (MEAMS): a preliminary investigation in people with probable dementia.

Science.gov (United States)

Powell, T; Brooker, D J; Papadopolous, A

1993-05-01

Relative and absolute test-retest reliability of the MEAMS was examined in 12 subjects with probable dementia and 12 matched controls. Relative reliability was good. Measures of absolute reliability showed scores changing by up to 3 points over an interval of a week. A version effect was found to be in evidence.

Test-retest measurements of dopamine D{sub 1}-type receptors using simultaneous PET/MRI imaging

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Kaller, Simon; Patt, Marianne; Becker, Georg-Alexander; Luthardt, Julia; Meyer, Philipp M.; Werner, Peter; Barthel, Henryk; Bresch, Anke; Sabri, Osama [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Rullmann, Michael [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig (Germany); Girbardt, Johanna [Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig (Germany); Fritz, Thomas H. [Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig (Germany); University of Gent, Institute for Psychoacoustics and Electronic Music (IPEM), Ghent (Belgium); Hesse, Swen [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Leipzig University Medical Centre, Integrated Research and Treatment Centre (IFB) Adiposity Diseases, Leipzig (Germany)

2017-06-15

The role of dopamine D{sub 1}-type receptor (D{sub 1}R)-expressing neurons in the regulation of motivated behavior and reward prediction has not yet been fully established. As a prerequisite for future research assessing D{sub 1}-mediated neuronal network regulation using simultaneous PET/MRI and D{sub 1}R-selective [{sup 11}C]SCH23390, this study investigated the stability of central D{sub 1}R measurements between two independent PET/MRI sessions under baseline conditions. Thirteen healthy volunteers (7 female, age 33 ± 13 yrs) underwent 90-min emission scans, each after 90-s bolus injection of 486 ± 16 MBq [{sup 11}C]SCH23390, on two separate days within 2-4 weeks using a PET/MRI system. Parametric images of D{sub 1}R distribution volume ratio (DVR) and binding potential (BP{sub ND}) were generated by a multi-linear reference tissue model with two parameters and the cerebellar cortex as receptor-free reference region. Volume-of-interest (VOI) analysis was performed with manual VOIs drawn on consecutive transverse MRI slices for brain regions with high and low D{sub 1}R density. The DVR varied from 2.5 ± 0.3 to 2.9 ± 0.5 in regions with high D{sub 1}R density (e.g. the head of the caudate) and from 1.2 ± 0.1 to 1.6 ± 0.2 in regions with low D{sub 1}R density (e.g. the prefrontal cortex). The absolute variability of the DVR ranged from 2.4% ± 1.3% to 5.1% ± 5.3%, while Bland-Altman analyses revealed very low differences in mean DVR (e.g. 0.013 ± 0.17 for the nucleus accumbens). Intraclass correlation (one-way, random) indicated very high agreement (0.93 in average) for both DVR and BP{sub ND} values. Accordingly, the absolute variability of BP{sub ND} ranged from 7.0% ± 4.7% to 12.5% ± 10.6%; however, there were regions with very low D{sub 1}R content, such as the occipital cortex, with higher mean variability. The test-retest reliability of D{sub 1}R measurements in this study was very high. This was the case not only for D{sub 1}R-rich brain areas, but

Evaluation of analytical reconstruction with a new gap-filling method in comparison to iterative reconstruction in [11C]-raclopride PET studies

International Nuclear Information System (INIS)

Tuna, U.; Johansson, J.; Ruotsalainen, U.

2014-01-01

The aim of the study was (1) to evaluate the reconstruction strategies with dynamic [ 11 C]-raclopride human positron emission tomography (PET) studies acquired from ECAT high-resolution research tomograph (HRRT) scanner and (2) to justify for the selected gap-filling method for analytical reconstruction with simulated phantom data. A new transradial bicubic interpolation method has been implemented to enable faster analytical 3D-reprojection (3DRP) reconstructions for the ECAT HRRT PET scanner data. The transradial bicubic interpolation method was compared to the other gap-filling methods visually and quantitatively using the numerical Shepp-Logan phantom. The performance of the analytical 3DRP reconstruction method with this new gap-filling method was evaluated in comparison with the iterative statistical methods: ordinary Poisson ordered subsets expectation maximization (OPOSEM) and resolution modeled OPOSEM methods. The image reconstruction strategies were evaluated using human data at different count statistics and consequently at different noise levels. In the assessments, 14 [ 11 C]-raclopride dynamic PET studies (test-retest studies of 7 healthy subjects) acquired from the HRRT PET scanner were used. Besides the visual comparisons of the methods, we performed regional quantitative evaluations over the cerebellum, caudate and putamen structures. We compared the regional time-activity curves (TACs), areas under the TACs and binding potential (BP ND ) values. The results showed that the new gap-filling method preserves the linearity of the 3DRP method. Results with the 3DRP after gap-filling method exhibited hardly any dependency on the count statistics (noise levels) in the sinograms while we observed changes in the quantitative results with the EM-based methods for different noise contamination in the data. With this study, we showed that 3DRP with transradial bicubic gap-filling method is feasible for the reconstruction of high-resolution PET data with

Synthesis of [11C]cyanoalkyltriphenylphosphoranes via [11C]cyanide substitution on haloalkylphosphonium salts

International Nuclear Information System (INIS)

Hoernfeldt, K.

1994-01-01

The synthesis of the 11 C-labelled bifunctional precursors 3-[ 11 C]cyanoethyltriphenylphosphonium bromide (1'), 4-[ 11 C]cyanopropyltriphenylphosphonium bromide (2'), 5-[ 11 C]cyanobutyltriphenylphosphonium bromide (3'), 4-[ 11 C]cyanopropyltriphenylphosphonium iodide (4') and 5-[ 11 C]cyanobutyltriphenylphosphonium iodide (5') is presented. The label was introduced using [ 11 C]cyanide in a substitution reaction on the ω-halo-alkyltriphenylphosphonium salt (bromide or iodide salt). The phosphonium salts 1'-5' were formed in 33-99% radiochemical yield in 5-10 min reaction time. After addition of epichlorohydrin as generator of base, the precursors 1-3 were formed. The potential of the intermediates 1-3 in Wittig reactions was shown in model reactions with aromatic and aliphatic aldehydes. The aromatic olefins obtained from 1'-5' were formed in 85-96% radiochemical yield, with Z/E ratios between 67/33-75/25. The aliphatic olefins were obtained in 60-78% radiochemical yield from 4' and 5'. In the reaction with 1' and an aliphatic aldehyde, the yield decreased to 5-10%. The Z/E ratios were 100/0 for the aliphatic olefins. In an experiment starting with 2,7 GBq (73 mCi) hydrogen [ 11 C]cyanide, 451 MBq (12.2 mCi) olefin from 3' and 4-nitrobenzaldehyde was obtained in 44 min from hydrogen [ 11 C]cyanide production, with a 55% decay corrected radiochemical yield, the radiochemical purity was 96%. (Author)

Prognostic Value and Reproducibility of Pretreatment CT Texture Features in Stage III Non-Small Cell Lung Cancer

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Fried, David V. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States); Tucker, Susan L. [Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zhou, Shouhao [Division of Quantitative Sciences, Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Liao, Zhongxing [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mawlawi, Osama [Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States); Ibbott, Geoffrey [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States); Court, Laurence E., E-mail: LECourt@mdanderson.org [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States)

2014-11-15

Purpose: To determine whether pretreatment CT texture features can improve patient risk stratification beyond conventional prognostic factors (CPFs) in stage III non-small cell lung cancer (NSCLC). Methods and Materials: We retrospectively reviewed 91 cases with stage III NSCLC treated with definitive chemoradiation therapy. All patients underwent pretreatment diagnostic contrast enhanced computed tomography (CE-CT) followed by 4-dimensional CT (4D-CT) for treatment simulation. We used the average-CT and expiratory (T50-CT) images from the 4D-CT along with the CE-CT for texture extraction. Histogram, gradient, co-occurrence, gray tone difference, and filtration-based techniques were used for texture feature extraction. Penalized Cox regression implementing cross-validation was used for covariate selection and modeling. Models incorporating texture features from the 33 image types and CPFs were compared to those with models incorporating CPFs alone for overall survival (OS), local-regional control (LRC), and freedom from distant metastases (FFDM). Predictive Kaplan-Meier curves were generated using leave-one-out cross-validation. Patients were stratified based on whether their predicted outcome was above or below the median. Reproducibility of texture features was evaluated using test-retest scans from independent patients and quantified using concordance correlation coefficients (CCC). We compared models incorporating the reproducibility seen on test-retest scans to our original models and determined the classification reproducibility. Results: Models incorporating both texture features and CPFs demonstrated a significant improvement in risk stratification compared to models using CPFs alone for OS (P=.046), LRC (P=.01), and FFDM (P=.005). The average CCCs were 0.89, 0.91, and 0.67 for texture features extracted from the average-CT, T50-CT, and CE-CT, respectively. Incorporating reproducibility within our models yielded 80.4% (±3.7% SD), 78.3% (±4.0% SD), and 78

Prognostic Value and Reproducibility of Pretreatment CT Texture Features in Stage III Non-Small Cell Lung Cancer

International Nuclear Information System (INIS)

Fried, David V.; Tucker, Susan L.; Zhou, Shouhao; Liao, Zhongxing; Mawlawi, Osama; Ibbott, Geoffrey; Court, Laurence E.

2014-01-01

Purpose: To determine whether pretreatment CT texture features can improve patient risk stratification beyond conventional prognostic factors (CPFs) in stage III non-small cell lung cancer (NSCLC). Methods and Materials: We retrospectively reviewed 91 cases with stage III NSCLC treated with definitive chemoradiation therapy. All patients underwent pretreatment diagnostic contrast enhanced computed tomography (CE-CT) followed by 4-dimensional CT (4D-CT) for treatment simulation. We used the average-CT and expiratory (T50-CT) images from the 4D-CT along with the CE-CT for texture extraction. Histogram, gradient, co-occurrence, gray tone difference, and filtration-based techniques were used for texture feature extraction. Penalized Cox regression implementing cross-validation was used for covariate selection and modeling. Models incorporating texture features from the 33 image types and CPFs were compared to those with models incorporating CPFs alone for overall survival (OS), local-regional control (LRC), and freedom from distant metastases (FFDM). Predictive Kaplan-Meier curves were generated using leave-one-out cross-validation. Patients were stratified based on whether their predicted outcome was above or below the median. Reproducibility of texture features was evaluated using test-retest scans from independent patients and quantified using concordance correlation coefficients (CCC). We compared models incorporating the reproducibility seen on test-retest scans to our original models and determined the classification reproducibility. Results: Models incorporating both texture features and CPFs demonstrated a significant improvement in risk stratification compared to models using CPFs alone for OS (P=.046), LRC (P=.01), and FFDM (P=.005). The average CCCs were 0.89, 0.91, and 0.67 for texture features extracted from the average-CT, T50-CT, and CE-CT, respectively. Incorporating reproducibility within our models yielded 80.4% (±3.7% SD), 78.3% (±4.0% SD), and 78

Intra-Rater, Inter-Rater and Test-Retest Reliability of an Instrumented Timed Up and Go (iTUG Test in Patients with Parkinson's Disease.

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Rob C van Lummel

Full Text Available The "Timed Up and Go" (TUG is a widely used measure of physical functioning in older people and in neurological populations, including Parkinson's Disease. When using an inertial sensor measurement system (instrumented TUG [iTUG], the individual components of the iTUG and the trunk kinematics can be measured separately, which may provide relevant additional information.The aim of this study was to determine intra-rater, inter-rater and test-retest reliability of the iTUG in patients with Parkinson's Disease.Twenty eight PD patients, aged 50 years or older, were included. For the iTUG the DynaPort Hybrid (McRoberts, The Hague, The Netherlands was worn at the lower back. The device measured acceleration and angular velocity in three directions at a rate of 100 samples/s. Patients performed the iTUG five times on two consecutive days. Repeated measurements by the same rater on the same day were used to calculate intra-rater reliability. Repeated measurements by different raters on the same day were used to calculate intra-rater and inter-rater reliability. Repeated measurements by the same rater on different days were used to calculate test-retest reliability.Nineteen ICC values (15% were ≥ 0.9 which is considered as excellent reliability. Sixty four ICC values (49% were ≥ 0.70 and < 0.90 which is considered as good reliability. Thirty one ICC values (24% were ≥ 0.50 and < 0.70, indicating moderate reliability. Sixteen ICC values (12% were ≥ 0.30 and < 0.50 indicating poor reliability. Two ICT values (2% were < 0.30 indicating very poor reliability.In conclusion, in patients with Parkinson's disease the intra-rater, inter-rater, and test-retest reliability of the individual components of the instrumented TUG (iTUG was excellent to good for total duration and for turning durations, and good to low for the sub durations and for the kinematics of the SiSt and StSi. The results of this fully automated analysis of instrumented TUG movements

Conversion of no-carrier-added [11C]carbon dioxide to [11C]carbon monoxide on molybdenum for the synthesis of 11C-labelled aromatic ketones

International Nuclear Information System (INIS)

Zeisler, S.K.; Nader, M.; Theobald, A.; Oberdorfer, F.

1997-01-01

A new method for the efficient conversion of no-carrier-added [ 11 C]carbon dioxide into [ 11 C]carbon monoxide is described. [ 11 C]Carbon dioxide produced by proton bombardment of ultra high purity nitrogen is pre-concentrated in a cryo trap and then passed through a quartz tube filled with a mesh of thin molybdenum wire heated to 850 o C. [ 11 C]Carbon dioxide readily reacts with molybdenum to form [ 11 C]carbon monoxide and molybdenum(IV) oxide. The latter also reduces carbon dioxide to carbon monoxide and helps improve the performance of the converter. [ 11 C]Carbon monoxide is purified from remaining [ 11 C]carbon dioxide and collected in a small silica trap from which it is eluted into a reaction mixture for the palladium-mediated synthesis of a 11 C-labelled aromatic ketone. Radiochemical yields of up to 81% (decay-corrected) for [ 11 C]carbon monoxide were obtained. Radiochemical purity and specific radioactivity of both [ 11 C]carbon monoxide and the 11 C-labelled ketone are sufficient for nuclear medical studies with PET. (Author)

Evaluation of 12 blood glucose monitoring systems for self-testing: system accuracy and measurement reproducibility.

Science.gov (United States)

Freckmann, Guido; Baumstark, Annette; Schmid, Christina; Pleus, Stefan; Link, Manuela; Haug, Cornelia

2014-02-01

Systems for self-monitoring of blood glucose (SMBG) have to provide accurate and reproducible blood glucose (BG) values in order to ensure adequate therapeutic decisions by people with diabetes. Twelve SMBG systems were compared in a standardized manner under controlled laboratory conditions: nine systems were available on the German market and were purchased from a local pharmacy, and three systems were obtained from the manufacturer (two systems were available on the U.S. market, and one system was not yet introduced to the German market). System accuracy was evaluated following DIN EN ISO (International Organization for Standardization) 15197:2003. In addition, measurement reproducibility was assessed following a modified TNO (Netherlands Organization for Applied Scientific Research) procedure. Comparison measurements were performed with either the glucose oxidase method (YSI 2300 STAT Plus™ glucose analyzer; YSI Life Sciences, Yellow Springs, OH) or the hexokinase method (cobas(®) c111; Roche Diagnostics GmbH, Mannheim, Germany) according to the manufacturer's measurement procedure. The 12 evaluated systems showed between 71.5% and 100% of the measurement results within the required system accuracy limits. Ten systems fulfilled with the evaluated test strip lot minimum accuracy requirements specified by DIN EN ISO 15197:2003. In addition, accuracy limits of the recently published revision ISO 15197:2013 were applied and showed between 54.5% and 100% of the systems' measurement results within the required accuracy limits. Regarding measurement reproducibility, each of the 12 tested systems met the applied performance criteria. In summary, 83% of the systems fulfilled with the evaluated test strip lot minimum system accuracy requirements of DIN EN ISO 15197:2003. Each of the tested systems showed acceptable measurement reproducibility. In order to ensure sufficient measurement quality of each distributed test strip lot, regular evaluations are required.

TEST-RETEST RELIABILITY OF HAND GRIP STRENGTH MEASUREMENT USING A JAMAR HAND DYNAMOMETER IN PATIENTS WITH ACUTE AND CHRONIC CERVICAL RADICULOPATHY

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Ejazi G

2017-12-01

Full Text Available Background: To evaluate the test-retest reliability of Jamar hand held dynamometer for measuring handgrip strength (HGS in patients with acute and chronic cervical radiculopathy and to find out the difference in measurement of the handgrip strength between acute and chronic cervical radiculopathy. Methods: A prospective, observational and non-experimental, the comparative study design was used. A sample of 72 subjects (37 women and 35 men suffering from cervical radiculopathy were divided into two groups i.e., Group A(acute and Group B(chronic, handgrip strength was measured using Jamar hand held dynamometer on two occasions by the same rater with an interval of 7-days. Data collection was based on standard guidelines of American Society of Hand Therapists. Three gripping trials (measured in Kg with patient’s arm in standardized arm position were recorded. The data was analyzed from the mean score obtained from the sample. Result: One-way Analysis of Variance(ANOVA was used to evaluate test-retest reliability and Tukey-Kramer Multiple Comparison Test used to find the difference between handgrip strength among acute and chronic Cervical radiculopathy cases. Greater P-value (>0.05 in both testing session, as well as 95% of the confidence interval, shows the reliability of the instrument and lesser p-value (0.05 in female subjects shows no significant difference in handgrip strength between the two groups. Conclusion: Excellent test-retest reliability for hand grip strength measurement was measured in patients with acute and chronic cervical radiculopathy shows that the equipment could be used as an assessment tool for this patient and significant difference exists among male handgrip strength between acute and chronic cervical radiculopathy cases whereas no difference exists among female handgrip strength between acute and chronic cervical radiculopathy cases.

Test-retest reliability and minimal detectable change of two simplified 3-point balance measures in patients with stroke.

Science.gov (United States)

Chen, Yi-Miau; Huang, Yi-Jing; Huang, Chien-Yu; Lin, Gong-Hong; Liaw, Lih-Jiun; Lee, Shih-Chieh; Hsieh, Ching-Lin

2017-10-01

The 3-point Berg Balance Scale (BBS-3P) and 3-point Postural Assessment Scale for Stroke Patients (PASS-3P) were simplified from the BBS and PASS to overcome the complex scoring systems. The BBS-3P and PASS-3P were more feasible in busy clinical practice and showed similarly sound validity and responsiveness to the original measures. However, the reliability of the BBS-3P and PASS-3P is unknown limiting their utility and the interpretability of scores. We aimed to examine the test-retest reliability and minimal detectable change (MDC) of the BBS-3P and PASS-3P in patients with stroke. Cross-sectional study. The rehabilitation departments of a medical center and a community hospital. A total of 51 chronic stroke patients (64.7% male). Both balance measures were administered twice 7 days apart. The test-retest reliability of both the BBS-3P and PASS-3P were examined by intraclass correlation coefficients (ICC). The MDC and its percentage over the total score (MDC%) of each measure was calculated for examining the random measurement errors. The ICC values of the BBS-3P and PASS-3P were 0.99 and 0.97, respectively. The MDC% (MDC) of the BBS-3P and PASS-3P were 9.1% (5.1 points) and 8.4% (3.0 points), respectively, indicating that both measures had small and acceptable random measurement errors. Our results showed that both the BBS-3P and the PASS-3P had good test-retest reliability, with small and acceptable random measurement error. These two simplified 3-level balance measures can provide reliable results over time. Our findings support the repeated administration of the BBS-3P and PASS-3P to monitor the balance of patients with stroke. The MDC values can help clinicians and researchers interpret the change scores more precisely.

Galbahe C1 y C2 Tests de Lengua (Castellano. Escalas 1 y 2). Medida del nivel de Castellano para ninos de 7-8 y 10-11 anos. Manual de Aplicacion. Glotodidaktika-Lanak 27. (Galbahe Language Tests C1 and C2--Spanish, Scales 1 and 2. Measure of Level of Spanish for Children 7-8 and 10-11 years. Test administration Manual. Glotodidaktika-Lanak Series Number 27).

Science.gov (United States)

Sierra, Josu; Olaziregi, Ibon

The Galbahe Language Tests C1 and C2 measure the Spanish language proficiency of children aged 7 to 8 years (C1) and those aged 10 to 11 years (C2). Equivalent tests E1 and E2 measure the Basque language achievement of the same age groups, respectively. Both tests were designed as part of a study of teaching of the Basque language in parts of…

Test-retest paradigm of the forced swimming test in female mice is not valid for predicting antidepressant-like activity: participation of acetylcholine and sigma-1 receptors.

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Su, Jing; Hato-Yamada, Noriko; Araki, Hiroaki; Yoshimura, Hiroyuki

2013-01-01

The forced swimming test (FST) in mice is widely used to predict the antidepressant activity of a drug, but information describing the immobility of female mice is limited. We investigated whether a prior swimming experience affects the immobility duration in a second FST in female mice and whether the test-retest paradigm is a valid screening tool for antidepressants. Female ICR mice were exposed to the FST using two experimental paradigms: a single FST and a double FST in which mice had experienced FST once 24 h prior to the second trail. The initial FST experience reliably prolonged immobility duration in the second FST. The antidepressants imipramine and paroxetine significantly reduced immobility duration in the single FST, but not in the double FST. Scopolamine and the sigma-1 (σ1) antagonist NE-100 administered before the second trial significantly prevented the prolongation of immobility. Neither a 5-HT1A nor a 5-HT2A receptor agonist affected immobility duration. We suggest that the test-retest paradigm in female mice is not adequate for predicting antidepressant-like activity of a drug; the prolongation of immobility in the double FST is modulated through acetylcholine and σ1 receptors.

Reproducibility of optically stimulated luminescence measurements from single grains of Al₂O₃: C and annealed quartz

DEFF Research Database (Denmark)

Truscott, A.J.; Duller, G.A.T.; Bøtter-Jensen, L.

2000-01-01

of nine-by-nine holes, which are drilled in the sample disc, We report on tests carried out to determine the precision with which the laser beam can be directed at individual grains in these holes. Single grains of aluminium oxide (Al2O3:C) (90-180 mum) and annealed quartz (90-120 mum) were used to test...... the reproducibility with which the OSL signal can be measured. These experiments suggest that the laser beam can be positioned to within 30 mum and that the reproducibility of OSL measurement is 3.5% on an average. (C) 2000 Elsevier Science Ltd. All rights reserved....

Reaction of 11 C-benzoyl chlorides with metalloid reagents: 11 C-labeling of benzyl alcohols, benzaldehydes, and phenyl ketones from [11 C]CO.

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Roslin, Sara; Dahl, Kenneth; Nordeman, Patrik

2018-01-26

In this article, we describe the carbon-11 ( 11 C, t 1/2  = 20.4 minutes) labeling of benzyl alcohols, benzaldehydes, and ketones using an efficient 2-step synthesis in which 11 C-carbon monoxide is used in an initial palladium-mediated reaction to produce 11 C-benzoyl chloride as a key intermediate. In the second step, the obtained 11 C-benzoyl chloride is further treated with a metalloid reagent to furnish the final 11 C-labeled product. Benzyl alcohols were obtained in moderated to high non-isolated radiochemical yields (RCY, 35%-90%) with lithium aluminum hydride or lithium aluminum deuteride as metalloid reagent. Changing the metalloid reagent to either tributyltin hydride or sodium borohydride, allowed for the reliable syntheses of 11 C-benzaldehydes in RCYs ranging from 58% to 95%. Finally, sodium tetraphenylborate were utilized to obtain 11 C-phenyl ketones in high RCYs (77%-95%). The developed method provides a new and efficient route to 3 different classes of compounds starting from aryl iodides or aryl bromides. Copyright © 2018 John Wiley & Sons, Ltd.

In vivo evaluation of [123I]mZIENT as a SPECT radioligand for the serotonin transporter

International Nuclear Information System (INIS)

Batis, Jeffery; Barret, Olivier; Alagille, David; Koren, Andrei O.; Stehouwer, Jeffrey S.; Cosgrove, Kelly; Goodman, Mark; Seibyl, John; Tamagnan, Gilles

2012-01-01

Introduction: In vivo imaging of the serotonin transporter continues to be a valuable tool in drug development and in monitoring diseases that alter serotonergic function. The purposes of this study were to: 1) evaluate the test/retest reproducibility of [ 123 I] 2β-Carbomethoxy-3β-(3′-((Z)-2-iodoethenyl)phenyl)nortropane ([ 123 I]mZIENT); and 2) to assess displacement of [ 123 I]mZIENT following administration of SERT specific drugs. Methods: Six female baboons (Papio anubis) were scanned following i.v. administration of [ 123 I]mZIENT. The regional binding potential (BP nd ) was determined using a simplified reference tissue model, with the cerebellum used as a reference region. The test/retest reproducibility of BP nd was determined following repeated injection of [ 123 I]mZIENT on a different day. To assess the displacement of [ 123 I]mZIENT from SERT, citalopram (0.01–5 mg/kg) or sertraline (0.01–0.5 mg/kg) was given as iv bolus at ∼ 4 h following administration of [ 123 I]mZIENT. Results: The test/retest variability of BP nd was less than 10% for all SERT-rich brain regions. Estimates of ED50 for displacement of [ 123 I]mZIENT in SERT-rich regions were consistent with previous reports for the [ 11 C] analog of [ 123 I]mZIENT. Both citalopram and sertraline displaced [ 123 I]mZIENT from SERT in a dose-dependent manner, with maximal observed displacements of greater than 80% in the diencephalon and greater than 75% in brainstem for both citalopram and sertraline. Conclusions: [ 123 I] mZIENT demonstrates good test–retest reproducibility; and initial displacement studies suggest that this compound is highly selective for SERT. Overall, this radioligand has favorable characteristics for use in drug development studies and/or longitudinal studies interrogating SERT.

Bad Behavior: Improving Reproducibility in Behavior Testing.

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Andrews, Anne M; Cheng, Xinyi; Altieri, Stefanie C; Yang, Hongyan

2018-01-24

Systems neuroscience research is increasingly possible through the use of integrated molecular and circuit-level analyses. These studies depend on the use of animal models and, in many cases, molecular and circuit-level analyses. Associated with genetic, pharmacologic, epigenetic, and other types of environmental manipulations. We illustrate typical pitfalls resulting from poor validation of behavior tests. We describe experimental designs and enumerate controls needed to improve reproducibility in investigating and reporting of behavioral phenotypes.

Can target-to-pons ratio be used as a reliable method for the analysis of [11C]PIB brain scans?

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Edison, P; Hinz, R; Ramlackhansingh, A; Thomas, J; Gelosa, G; Archer, H A; Turkheimer, F E; Brooks, D J

2012-04-15

(11)C]PIB is the most widely used PET imaging marker for amyloid in dementia studies. In the majority of studies the cerebellum has been used as a reference region. However, cerebellar amyloid may be present in genetic Alzheimer's (AD), cerebral amyloid angiopathy and prion diseases. Therefore, we investigated whether the pons could be used as an alternative reference region for the analysis of [(11)C]PIB binding in AD. The aims of the study were to: 1) Evaluate the pons as a reference region using arterial plasma input function and Logan graphical analysis of binding. 2) Assess the power of target-to-pons ratios to discriminate controls from AD subjects. 3) Determine the test-retest reliability in AD subjects. 4) Demonstrate the application of target-to-pons ratio in subjects with elevated cerebellar [(11)C]PIB binding. 12 sporadic AD subjects aged 65 ± 4.5 yrs with a mean MMSE 21.4 ± 4 and 10 age-matched control subjects had [(11)C]PIB PET with arterial blood sampling. Three additional subjects (two subjects with pre-symptomatic presenilin-1 mutation carriers and one probable familial AD) were also studied. Object maps were created by segmenting individual MRIs and spatially transforming the gray matter images into standard stereotaxic MNI space and then superimposing a probabilistic atlas. Cortical [(11)C]PIB binding was assessed with an ROI (region of interest) analysis. Parametric maps of the volume of distribution (V(T)) were generated with Logan analysis. Additionally, parametric maps of the 60-90 min target-to-cerebellar ratio (RATIO(CER)) and the 60-90 min target-to-pons ratio (RATIO(PONS)) were computed. All three approaches were able to differentiate AD from controls (p0.83); RATIO(CER) performed best closely followed by RATIO(PONS). The two subjects with presenilin-1 mutations and the probable familial AD case showed no significant differences in cortical binding using RATIO(CER), but the RATIO(PONS) approach revealed higher [(11)C]PIB binding in

Test-retest reliability and agreement of the Satisfaction with the Assistive Technology Services (SATS) instrument in two Nordic countries.

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Sund, Terje; Iwarsson, Susanne; Anttila, Heidi; Helle, Tina; Brandt, Ase

2014-07-01

The purpose of this study was to investigate test-retest reliability, agreement, internal consistency, and floor- and ceiling effects of the Danish and Finnish versions of the Satisfaction with the Assistive Technology Services (SATS) instrument among adult users of powered wheelchairs (PWCs) or powered scooters (scooters). Test-retest design, two telephone interviews 7-18 days apart of 40 informants, with mean age of 67.5 (SD 13.09) years in the Danish; and 54 informants with mean age of 55.6 (SD 12.09) years in the Finnish sample. The intra-class correlation coefficient varied between 0.57 and 0.93 for items in the Danish and between 0.41 and 0.93 in the Finnish sample. The percentage agreement varied between 54.2 and 79.5 for items in the Danish and between 69.2 and 81.1 in the Finnish sample, while the Cronbach's alpha values varied between 0.87 and 0.96 in the two samples. A ceiling effect was found in all items of both samples. This study indicates that the SATS may be reliably administered for telephone interviews among adult PWC and scooter users, and give information about aspects of the service delivery process for quality development improvement purposes. Further psychometric testing of the SATS is required.

Test-Retest Reliability of Dual-Task Outcome Measures in People With Parkinson Disease.

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Strouwen, Carolien; Molenaar, Esther A L M; Keus, Samyra H J; Münks, Liesbeth; Bloem, Bastiaan R; Nieuwboer, Alice

2016-08-01

Dual-task (DT) training is gaining ground as a physical therapy intervention in people with Parkinson disease (PD). Future studies evaluating the effect of such interventions need reliable outcome measures. To date, the test-retest reliability of DT measures in patients with PD remains largely unknown. The purpose of this study was to assess the reliability of DT outcome measures in patients with PD. A repeated-measures design was used. Patients with PD ("on" medication, Mini-Mental State Examination score ≥24) performed 2 cognitive tasks (ie, backward digit span task and auditory Stroop task) and 1 functional task (ie, mobile phone task) in combination with walking. Tasks were assessed at 2 time points (same hour) with an interval of 6 weeks. Test-retest reliability was assessed for gait while performing each secondary task (DT gait) for both cognitive tasks while walking (DT cognitive) and for the functional task while walking (DT functional). Sixty-two patients with PD (age=39-89 years, Hoehn and Yahr stages II-III) were included in the study. Intraclass correlation coefficients (ICCs) showed excellent reliability for DT gait measures, ranging between .86 and .95 when combined with the digit span task, between .86 and .95 when combined with the auditory Stroop task, and between .72 and .90 when combined with the mobile phone task. The standard error of measurements for DT gait speed varied between 0.06 and 0.08 m/s, leading to minimal detectable changes between 0.16 and 0.22 m/s. With regard to DT cognitive measures, reaction times showed good-to-excellent reliability (digit span task: ICC=.75; auditory Stroop task: ICC=.82). The results cannot be generalized to patients with advanced disease or to other DT measures. In people with PD, DT measures proved to be reliable for use in clinical studies and look promising for use in clinical practice to assess improvements after DT training. Large effects, however, are needed to obtain meaningful effect sizes. �

Reproducibility Test for Thermoluminescence Dosimeter (TLD) Using TLD Radpro

International Nuclear Information System (INIS)

Nur Khairunisa Zahidi; Ahmad Bazlie Abdul Kadir; Faizal Azrin Abdul Razalim

2016-01-01

Thermoluminescence dosimeters (TLD) as one type of dosimeter which are often used to substitute the film badge. Like a film badge, it is worn for a period of time and then must be processed to determine the dose received. This study was to test the reproducibility of TLD using Radpro reader. This study aimed to determine the dose obtained by TLD-100 chips when irradiated with Co-60 gamma source and to test the effectiveness of TLD Radpro reader as a machine to analyse the TLD. Ten chips of TLD -100 were irradiated using Eldorado machine with Co-60 source at a distance of 5 meters from the source with 2 mSv dose exposure. After the irradiation process, TLD-100 chips were read using the TLD Radpro reader. These steps will be repeated for nine times to obtain reproducibility coefficient, r i . The readings of dose obtained from experiment was almost equivalent to the actual dose. Results shows that the average value obtained for reproducibility coefficient, r i is 6.39 % which is less than 10 %. As conclusion, the dose obtained from experiment considered accurate because its value were almost equivalent to the actual dose and TLD Radpro was verified as a good reader to analyse the TLD. (author)

HiCRep: assessing the reproducibility of Hi-C data using a stratum-adjusted correlation coefficient.

Science.gov (United States)

Yang, Tao; Zhang, Feipeng; Yardımcı, Galip Gürkan; Song, Fan; Hardison, Ross C; Noble, William Stafford; Yue, Feng; Li, Qunhua

2017-11-01

Hi-C is a powerful technology for studying genome-wide chromatin interactions. However, current methods for assessing Hi-C data reproducibility can produce misleading results because they ignore spatial features in Hi-C data, such as domain structure and distance dependence. We present HiCRep, a framework for assessing the reproducibility of Hi-C data that systematically accounts for these features. In particular, we introduce a novel similarity measure, the stratum adjusted correlation coefficient (SCC), for quantifying the similarity between Hi-C interaction matrices. Not only does it provide a statistically sound and reliable evaluation of reproducibility, SCC can also be used to quantify differences between Hi-C contact matrices and to determine the optimal sequencing depth for a desired resolution. The measure consistently shows higher accuracy than existing approaches in distinguishing subtle differences in reproducibility and depicting interrelationships of cell lineages. The proposed measure is straightforward to interpret and easy to compute, making it well-suited for providing standardized, interpretable, automatable, and scalable quality control. The freely available R package HiCRep implements our approach. © 2017 Yang et al.; Published by Cold Spring Harbor Laboratory Press.

The Harm Done to Reproducibility by the Culture of Null Hypothesis Significance Testing.

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Lash, Timothy L

2017-09-15

In the last few years, stakeholders in the scientific community have raised alarms about a perceived lack of reproducibility of scientific results. In reaction, guidelines for journals have been promulgated and grant applicants have been asked to address the rigor and reproducibility of their proposed projects. Neither solution addresses a primary culprit, which is the culture of null hypothesis significance testing that dominates statistical analysis and inference. In an innovative research enterprise, selection of results for further evaluation based on null hypothesis significance testing is doomed to yield a low proportion of reproducible results and a high proportion of effects that are initially overestimated. In addition, the culture of null hypothesis significance testing discourages quantitative adjustments to account for systematic errors and quantitative incorporation of prior information. These strategies would otherwise improve reproducibility and have not been previously proposed in the widely cited literature on this topic. Without discarding the culture of null hypothesis significance testing and implementing these alternative methods for statistical analysis and inference, all other strategies for improving reproducibility will yield marginal gains at best. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Multilevel Factor Structure, Concurrent Validity, and Test-Retest Reliability of the High School Teacher Version of the Authoritative School Climate Survey

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Huang, Francis L.; Cornell, Dewey G.

2016-01-01

Although school climate has long been recognized as an important factor in the school improvement process, there are few psychometrically supported measures based on teacher perspectives. The current study replicated and extended the factor structure, concurrent validity, and test-retest reliability of the teacher version of the Authoritative…

Reproducibility of myelin content-based human habenula segmentation at 3 Tesla.

Science.gov (United States)

Kim, Joo-Won; Naidich, Thomas P; Joseph, Joshmi; Nair, Divya; Glasser, Matthew F; O'halloran, Rafael; Doucet, Gaelle E; Lee, Won Hee; Krinsky, Hannah; Paulino, Alejandro; Glahn, David C; Anticevic, Alan; Frangou, Sophia; Xu, Junqian

2018-03-26

In vivo morphological study of the human habenula, a pair of small epithalamic nuclei adjacent to the dorsomedial thalamus, has recently gained significant interest for its role in reward and aversion processing. However, segmenting the habenula from in vivo magnetic resonance imaging (MRI) is challenging due to the habenula's small size and low anatomical contrast. Although manual and semi-automated habenula segmentation methods have been reported, the test-retest reproducibility of the segmented habenula volume and the consistency of the boundaries of habenula segmentation have not been investigated. In this study, we evaluated the intra- and inter-site reproducibility of in vivo human habenula segmentation from 3T MRI (0.7-0.8 mm isotropic resolution) using our previously proposed semi-automated myelin contrast-based method and its fully-automated version, as well as a previously published manual geometry-based method. The habenula segmentation using our semi-automated method showed consistent boundary definition (high Dice coefficient, low mean distance, and moderate Hausdorff distance) and reproducible volume measurement (low coefficient of variation). Furthermore, the habenula boundary in our semi-automated segmentation from 3T MRI agreed well with that in the manual segmentation from 7T MRI (0.5 mm isotropic resolution) of the same subjects. Overall, our proposed semi-automated habenula segmentation showed reliable and reproducible habenula localization, while its fully-automated version offers an efficient way for large sample analysis. © 2018 Wiley Periodicals, Inc.

The interrater and test-retest reliability of the Home Falls and Accidents Screening Tool (HOME FAST) in Malaysia: Using raters with a range of professional backgrounds.

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Romli, Muhammad Hibatullah; Mackenzie, Lynette; Lovarini, Meryl; Tan, Maw Pin; Clemson, Lindy

2017-06-01

Falls can be a devastating issue for older people living in the community, including those living in Malaysia. Health professionals and community members have a responsibility to ensure that older people have a safe home environment to reduce the risk of falls. Using a standardised screening tool is beneficial to intervene early with this group. The Home Falls and Accidents Screening Tool (HOME FAST) should be considered for this purpose; however, its use in Malaysia has not been studied. Therefore, the aim of this study was to evaluate the interrater and test-retest reliability of the HOME FAST with multiple professionals in the Malaysian context. A cross-sectional design was used to evaluate interrater reliability where the HOME FAST was used simultaneously in the homes of older people by 2 raters and a prospective design was used to evaluate test-retest reliability with a separate group of older people at different times in their homes. Both studies took place in an urban area of Kuala Lumpur. Professionals from 9 professional backgrounds participated as raters in this study, and a group of 51 community older people were recruited for the interrater reliability study and another group of 30 for the test-retest reliability study. The overall agreement was moderate for interrater reliability and good for test-retest reliability. The HOME FAST was consistently rated by different professionals, and no bias was found among the multiple raters. The HOME FAST can be used with confidence by a variety of professionals across different settings. The HOME FAST can become a universal tool to screen for home hazards related to falls. © 2017 John Wiley & Sons, Ltd.

Test-retest reliability of diffusion tensor imaging of the liver at 3.0 T.

Science.gov (United States)

Girometti, Rossano; Maieron, Marta; Lissandrello, Giovanni; Bazzocchi, Massimo; Zuiani, Chiara

2015-06-01

This study was done to evaluate test-retest reliability of liver diffusion tensor imaging (LDTI). Ten healthy volunteers (median age 23 years) underwent two LDTI scans on a 3.0 T magnet during two imaging sessions separated by 2 weeks (session-1/-2, respectively). Fifteen gradient directions and b values of 0-1,000 s/mm(2) were used. Two radiologists in consensus assessed liver apparent diffusion coefficient (ADC) and fraction of anisotropy (FA) values on ADC and FA maps at four reference levels, namely: right upper level (RUL), right lower level (RLL), left upper level (LUL) and left lower level (LLL). We then assessed (a) whether ADC and FA values overlapped when measured on different levels within the same imaging session or between different imaging sessions; (b) the degree of variability on an intra-session and inter-session basis, respectively, using the coefficient of variation (CV). In sessions 1 and 2, the ADC/FA values were significantly larger in the left liver lobe (LUL/LLL) compared to right liver lobe (RUL/RLL) (p < 0.05/6). Intra-session CVs were 9.51 % (session 1) and 9.73 % (session 2) for ADC, and 12.93 % (session 1) and 11.82 % (session 2) for FA, respectively. When comparing RUL, RLL, LUL and LLL on an inter-session basis, CVs were 6.52, 8.20, 6.52 and 11.06 % for ADC, and 15.42, 15.80, 15.42 and 6.80 % for FA, respectively. LDTI provides consistent and repeatable measurements. However, since larger left lobe ADC/FA values can be attributed to artefacts, right lobe values should be considered the most reliable measurements of water diffusivity within the liver.

Automation of cDNA Synthesis and Labelling Improves Reproducibility

Directory of Open Access Journals (Sweden)

Daniel Klevebring

2009-01-01

Full Text Available Background. Several technologies, such as in-depth sequencing and microarrays, enable large-scale interrogation of genomes and transcriptomes. In this study, we asses reproducibility and throughput by moving all laboratory procedures to a robotic workstation, capable of handling superparamagnetic beads. Here, we describe a fully automated procedure for cDNA synthesis and labelling for microarrays, where the purification steps prior to and after labelling are based on precipitation of DNA on carboxylic acid-coated paramagnetic beads. Results. The fully automated procedure allows for samples arrayed on a microtiter plate to be processed in parallel without manual intervention and ensuring high reproducibility. We compare our results to a manual sample preparation procedure and, in addition, use a comprehensive reference dataset to show that the protocol described performs better than similar manual procedures. Conclusions. We demonstrate, in an automated gene expression microarray experiment, a reduced variance between replicates, resulting in an increase in the statistical power to detect differentially expressed genes, thus allowing smaller differences between samples to be identified. This protocol can with minor modifications be used to create cDNA libraries for other applications such as in-depth analysis using next-generation sequencing technologies.

The Unsupported Upper Limb Exercise Test in People Without Disabilities: Assessing the Within-Day Test-Retest Reliability and the Effects of Age and Gender.

Science.gov (United States)

Oliveira, Ana; Cruz, Joana; Jácome, Cristina; Marques, Alda

2018-01-01

Purpose: To estimate the within-day test-retest reliability and standard error of measurement (SEM) of the unsupported upper limb exercise test (UULEX) in adults without disabilities and to determine the effects of age and gender on performance of the UULEX. Method: A cross-sectional study was conducted with 100 adults without disabilities (44 men, mean age 44.2 [SD 26] y; 56 women, mean age 38.1 [SD 24.1] y). Participants performed three UULEX tests to establish within-day reliability, measured using an intra-class correlation coefficient (ICC) model 2 (two-way random effects) with a single rater (ICC[2,1]) and SEM. The effects of age and gender were examined using two-factor mixed-design analysis of variance (ANOVA) and one-way repeated-measures ANOVA. For analysis purposes, four sub-groups were created: younger adults, older adults, men, and women. Results: Excellent within-day reliability and a small SEM were found in the four sub-groups (younger adults: ICC[2,1]=0.88; 95% CI: 0.82, 0.92; SEM∼40 s; older adults: ICC[2,1]=0.82; 95% CI: 0.72, 0.90; SEM∼50 s; men: ICC[2,1]=0.93; 95% CI: 0.88, 0.96; SEM∼30 s; women: ICC[2,1]=0.85; 95% CI: 0.78, 0.91; SEM∼45 s). Younger adults took, on average, 308.24 seconds longer than older adults to perform the test; older adults performed significantly better on the third test ( p 0.05). Conclusion: The within-day test-retest reliability and SEM values of the UULEX may be used to define the magnitude of the error obtained with repeated measures. One UULEX test seems to be adequate for younger adults to achieve reliable results, whereas three tests seem to be needed for older adults.

[11C]copper(I) cyanide: a new radioactive precursor or 11C-cyanation and functionalization of haloarenes

International Nuclear Information System (INIS)

Ponchant, M.; Hinnen, F.; Demphel, S.; Crouzel, C.

1997-01-01

Radiosyntheses of [cyano- 11 C]benzonitriles, [carboyxyl- 11 C]benzoic acids, [carbonyl- 11 C]benzamides and [tetrazoyl- 11 C]5-biphenyl-1H-tetrazoles are described. [Cyano- 11 C]benzonitriles were prepared using the Rosenmund-von Braun reaction in one step from [ 11 C]hydrogen cyanide via [ 11 C]copper(1) cyanide in 2 min. [Carboxyl- 11 C]benzoic acids and [carbonyl- 11 C]benzamides were prepared from [cyano- 11 C]benzonitrile-complexes using basic hydrogen peroxide for 3 min in N,N-dimethylformamide at 180 and 80 o C, respectively. [Tetrazoyl- 11 C]5-biphenyl-1H-tetrazoles were obtained from [cyano- 11 C]benzonitrile-complexes in 7 min by cyclization with trimethyltin azide followed by acid hydrolysis at 180 o C. These labelled compounds were obtained in a one-pot procedure with good average specific radioactivities [500 mCi/μmol) at the end of synthesis] and in satisfactory average radiochemical yields (24-69%) at 40 min from the end of radionuclide production. This new radioactive precursor, [ 11 C]copper(I) cyanide, should give access to new 11 C-labelled ligands for positron emission tomography. (author)

Banff initiative for quality assurance in transplantation (BIFQUIT): reproducibility of C4d immunohistochemistry in kidney allografts.

Science.gov (United States)

Mengel, M; Chan, S; Climenhaga, J; Kushner, Y B; Regele, H; Colvin, R B; Randhawa, P

2013-05-01

Detection of C4d is crucial for diagnosing antibody-mediated-rejection. We conducted a multicenter trial to assess the reproducibility for C4d immunohistochemistry on paraffin tissue. Unstained slides from a tissue microarray (TMA) comprising 44 kidney allograft specimens representing a full analytical spectrum for C4d were distributed to 73 institutions. Participants stained TMA slides using local protocols and evaluated their slides following the Banff C4d schema. Local staining details and evaluation scores were collected online. Stained slides were returned for centralized panel re-evaluation. Kappa statistics were used to determine reproducibility. Poor interinstitutional reproducibility was observed (kappa 0.17), which was equally due to limitations in interobserver (kappa 0.44) and interlaboratory reproducibility (kappa 0.46). Depending on the cut-off, reproducibility could be improved by omitting C4d grading and only considering ± calls. Heat-induced epitope recovery (pH 6-7, 20-30 min, citrate buffer) with polyclonal antibody incubation (40 min) appeared as best practice. The BIFQUIT trial results indicated that C4d staining on paraffin sections varies considerably between laboratories. Refinement of the current Banff C4d scoring schema and harmonization of tissue processing and staining protocols is necessary to achieve acceptable reproducibility. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

Effects of acute nicotine on hemodynamics and binding of [11C]raclopride to dopamine D2,3 receptors in pig brain.

Science.gov (United States)

Cumming, Paul; Rosa-Neto, Pedro; Watanabe, Hideaki; Smith, Donald; Bender, Dirk; Clarke, Paul B S; Gjedde, Albert

2003-07-01

Positive reinforcing properties of nicotine and the psychostimulants have been attributed to elevated dopamine release in the basal ganglia. It is well known that the specific binding of [(11)C]raclopride to dopamine D(2,3) receptors in living striatum is reduced by cocaine and amphetamines, revealing increased competition between endogenous dopamine and [(11)C]raclopride for dopamine D(2,3) receptors. However, the sensitivity of [(11)C]raclopride binding to nicotine-induced dopamine release is less well documented. In order to provide the basis for mapping effects of nicotine, we first optimized reference tissue methods for quantifying [(11)C]raclopride binding sites in striatum of living pigs (n = 16). In the same animals, the rate of cerebral blood flow (CBF) was mapped using [(15)O]water. Neither a low dose of nicotine (50 mu kg(-1), iv) nor a high dose of nicotine (500 microg kg(-1), iv) altered CBF in the pig brain, an important condition for calculating the binding of radioligands when using a reference tissue to estimate the free ligand concentration. The methods of Logan and of Lammertsma were compared using the cerebellum or the occipital cortex as reference tissues for calculating the binding potential (pB) of [(11)C]raclolpride in brain. Irrespective of the method used, the mean undrugged baseline pB in striatum (ca. 2.0) was significantly asymmetric, with highest binding in the left caudate and right putamen. Test-retest estimates of pB were stable. Subtraction of Logan pB maps revealed that the low dose of nicotine reduced the pB of [(11)C]raclopride by 10% in a cluster of voxels in the left anteroventral striatum, but this effect did not persist after correction for multiple comparisons. The high dose of nicotine (n = 9) acutely reduced pB by 10% bilaterally in the ventral striatum; 3 h after the high nicotine dose, the reductions had shifted dorsally and caudally into the caudate and putamen. Evidently, nicotine challenge enhances the competition

Synthesis of [11C]-Sarin

International Nuclear Information System (INIS)

Prenant, C.; Crouzel, C.

1990-01-01

[ 11 C]-acetone, prepared from 11 CO 2 and methyllithium, was reduced to [ 11 C]-isopropanol. The latter reacted with methylphosphonic acid difluoride in the presence of diisopropylamine, to yield [11C]-sarin. 3.4 GBq (100 mCi) of [ 11 C]-sarin may be obtained from about 55.5 GBq (1.5 Ci) of 11 CO 2 in 40 minutes. The product purified by HPLC, is obtained with a specific radioactivity ranging from 22.2 to 33.3 GBq (600 to 900 mCi/μmol.). (author)

Examination of reproducibility in microbiological degredation experiments

DEFF Research Database (Denmark)

Sommer, Helle Mølgaard; Spliid, Henrik; Holst, Helle

1998-01-01

Experimental data indicate that certain microbiological degradation experiments have a limited reproducibility. Nine identical batch experiments were carried out on 3 different days to examine reproducibility. A pure culture, isolated from soil, grew with toluene as the only carbon and energy...... source. Toluene was degraded under aerobic conditions at a constant temperature of 28 degreesC. The experiments were modelled by a Monod model - extended to meet the air/liquid system, and the parameter values were estimated using a statistical nonlinear estimation procedure. Model reduction analysis...... resulted in a simpler model without the biomass decay term. In order to test for model reduction and reproducibility of parameter estimates, a likelihood ratio test was employed. The limited reproducibility for these experiments implied that all 9 batch experiments could not be described by the same set...

Automated synthesis of 11C-carfentanil with 11C-choline module and micro PET imaging

International Nuclear Information System (INIS)

Zhang Jinming; Zhang Xiaojun; Tian Jiahe; Xu Zhihong; Xiang Xiaohui

2011-01-01

A simple modified home-made 11 C-choline module enabled to rapid and efficient synthesis 11 C-carfentanil ( 11 C-CFN) as CNS μ-opioid receptor imaging agent. The synthesis of 11 C-CFN was completed in a yield of 14.8 GBq within 18 min from 11 C-CO 2 on the choline module. The methylation took place from 4-piperidinecarboxylic acid, 4-[(1-oxopropyl) phenylamino]-l-(2-phenylethyl), sodium salt as precursor in DMSO solution. The radio- chemical yields were over 80% (n=55, decay-corrected and based on 11 CH 3 -triflate). The radiochemical purity was over 95% and the specific activities was over 1.4 × 10 14 Bq/g. The biologic activity of 11 C-CFN was confirmed with Micro PET/CT imaging. (authors)

Reproducibility of positive results for the detection of serum galactomannan by Platelia™ aspergillus EIA.

Science.gov (United States)

Pedroza, Kelly C M C; de Matos, Sócrates B; de Moura, Daniel L; Oliveira, Mônica B B; Araújo, Marco A S; Nascimento, Roberto J M; Lima, Fernanda W M

2013-10-01

Galactomannan (GM) was recently included in consensus guidelines as an indirect mycological criterion for the diagnosis of invasive aspergillosis. Currently, there is an enzyme immunoassay available to detect GM in biological samples, the Platelia™ Aspergillus EIA. In this study, the reproducibility of positive results obtained using this assay was evaluated using serum samples from neutropenic patients. A trend toward lower values was observed, and 55 %(27/49) of positive results were negative after retesting. A low reproducibility of positive results for the detection of GM in serum was observed.

Interaction between morphine and noradrenergic system of basolateral amygdala on anxiety and memory in the elevated plus-maze test based on a test-retest paradigm.

Science.gov (United States)

Valizadegan, Farhad; Oryan, Shahrbanoo; Nasehi, Mohammad; Zarrindast, Mohammad Reza

2013-05-01

The amygdala is the key brain structure for anxiety and emotional memory storage. We examined the involvement of β-adrenoreceptors in the basolateral amygdala (BLA) and their interaction with morphine in modulating these behaviors. The elevated plus-maze has been employed for investigating anxiety and memory. Male Wistar rats were used for this test. We injected morphine (4, 5, and 6 mg/kg) intraperitoneally, while salbutamol (albuterol) (1, 2, and 4 μg/rat) and propranolol (1, 2, and 4 μg/rat) were injected into the BLA. Open- arms time percentage (%OAT), open- arms entry percentage (%OAE), and locomotor activity were determined by this behavioral test. Retention was tested 24 hours later. Intraperitoneal injection of morphine (6 mg/kg) had an anxiolytic-like effect and improvement of memory. The highest dose of salbutamol decreased the anxiety parameters in test session and improved the memory in retest session. Coadministration of salbutamol and ineffective dose of morphine presenting anxiolytic response. In this case, the memory was improved. Intra-BLA administration of propranolol (4 μg/rat) decreased %OAT in the test session, while had no effect on memory formation. Coadministration of propranolol and morphine (6 mg/kg) showed an increase in %OAT. There was not any significant change in the above- mentioned parameter in the retest session. Coadministration of morphine and propranolol with the effective dose of salbutamol showed that propranolol could reverse anxiolytic-like effect. We found that opioidergic and β-adrenergic systems have the same effects on anxiety and memory in the BLA; but these effects are independent of each other.

In vivo positron emission tomography studies on the novel nicotinic receptor agonist [11C]MPA compared with [11C]ABT-418 and (S)(-)[11C]nicotine in Rhesus monkeys

International Nuclear Information System (INIS)

Sihver, Wiebke; Fasth, Karl-Johan; Oegren, Matthias; Lundqvist, Hans; Bergstroem, Mats; Watanabe, Yasuyoshi; Laangstroem, Bengt; Nordberg, Agneta

1999-01-01

The novel 11 C-labeled nicotinic agonist (R,S)-1-[ 11 C]methyl-2(3-pyridyl)azetidine ([ 11 C]MPA) was evaluated as a positron emission tomography (PET) ligand for in vivo characterization of nicotinic acetylcholine receptors in the brain of Rhesus monkeys in comparison with the nicotinic ligands (S)-3-methyl-5-(1-[ 11 C]methyl-2-pyrrolidinyl)isoxazol ([ 11 C]ABT-418) and (S)(-)[ 11 C]nicotine. The nicotinic receptor agonist [ 11 C]MPA demonstrated rapid uptake into the brain to a similar extent as (S)(-) [ 11 C]nicotine and [ 11 C]ABT-418. When unlabeled (S)(-)nicotine (0.02 mg/kg) was administered 5 min before the radioactive tracers, the uptake of [ 11 C]MPA was decreased by 25% in the thalamus, 19% in the temporal cortex, and 11% in the cerebellum, whereas an increase was found for the uptake of (S)(-)[ 11 C]nicotine and [ 11 C]ABT-418. This finding indicates specific binding of [ 11 C]MPA to nicotinic receptors in the brain in a simple classical displacement study. [ 11 C]MPA seems to be a more promising radiotracer than (S)(-)[ 11 C]nicotine or [ 11 C]ABT-418 for PET studies to characterize nicotinic receptors in the brain

Short-interval test-retest interrater reliability of the Dutch version of the structured clinical interview for DSM-IV personality disorders (SCID-II)

NARCIS (Netherlands)

Weertman, A; ArntZ, A; Dreessen, L; van Velzen, C; Vertommen, S

2003-01-01

This study examined the short-interval test-retest reliability of the Structured Clinical Interview (SCID-II: First, Spitzer, Gibbon, & Williams, 1995) for DSM-IV personality disorders (PDs). The SCID-II was administered to 69 in- and outpatients on two occasions separated by 1 to 6 weeks. The

Reproducibility and validity of the Shanghai Women's Health Study physical activity questionnaire.

Science.gov (United States)

Matthews, Charles E; Shu, Xiao-Ou; Yang, Gong; Jin, Fan; Ainsworth, Barbara E; Liu, Dake; Gao, Yu-Tang; Zheng, Wei

2003-12-01

In this investigation, the authors evaluated the reproducibility and validity of the Shanghai Women's Health Study (SWHS) physical activity questionnaire (PAQ), which was administered in a cohort study of approximately 75,000 Chinese women aged 40-70 years. Reproducibility (2-year test-retest) was evaluated using kappa statistics and intraclass correlation coefficients (ICCs). Validity was evaluated by comparing Spearman correlations (r) for the SWHS PAQ with two criterion measures administered over a period of 12 months: four 7-day physical activity logs and up to 28 7-day PAQs. Women were recruited from the SWHS cohort (n = 200). Results indicated that the reproducibility of adolescent and adult exercise participation (kappa = 0.85 and kappa = 0.64, respectively) and years of adolescent exercise and adult exercise energy expenditure (ICC = 0.83 and ICC = 0.70, respectively) was reasonable. Reproducibility values for adult lifestyle activities were lower (ICC = 0.14-0.54). Significant correlations between the PAQ and criterion measures of adult exercise were observed for the first PAQ administration (physical activity log, r = 0.50; 7-day PAQ, r = 0.62) and the second PAQ administration (physical activity log, r = 0.74; 7-day PAQ, r = 0.80). Significant correlations between PAQ lifestyle activities and the 7-day PAQ were also noted (r = 0.33-0.88). These data indicate that the SWHS PAQ is a reproducible and valid measure of exercise behaviors and that it demonstrates utility in stratifying women by levels of important lifestyle activities (e.g., housework, walking, cycling).

Test-retest reliability and construct validity of the ENERGY-parent questionnaire on parenting practices, energy balance-related behaviours and their potential behavioural determinants: the ENERGY-project

Directory of Open Access Journals (Sweden)

Singh Amika S

2012-08-01

Full Text Available Abstract Background Insight in parental energy balance-related behaviours, their determinants and parenting practices are important to inform childhood obesity prevention. Therefore, reliable and valid tools to measure these variables in large-scale population research are needed. The objective of the current study was to examine the test-retest reliability and construct validity of the parent questionnaire used in the ENERGY-project, assessing parental energy balance-related behaviours, their determinants, and parenting practices among parents of 10–12 year old children. Findings We collected data among parents (n = 316 in the test-retest reliability study; n = 109 in the construct validity study of 10–12 year-old children in six European countries, i.e. Belgium, Greece, Hungary, the Netherlands, Norway, and Spain. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC and percentage agreement comparing scores from two measurements, administered one week apart. To assess construct validity, the agreement between questionnaire responses and a subsequent interview was assessed using ICC and percentage agreement. All but one item showed good to excellent test-retest reliability as indicated by ICCs > .60 or percentage agreement ≥ 75%. Construct validity appeared to be good to excellent for 92 out of 121 items, as indicated by ICCs > .60 or percentage agreement ≥ 75%. From the other 29 items, construct validity was moderate for 24 and poor for 5 items. Conclusions The reliability and construct validity of the items of the ENERGY-parent questionnaire on multiple energy balance-related behaviours, their potential determinants, and parenting practices appears to be good. Based on the results of the validity study, we strongly recommend adapting parts of the ENERGY-parent questionnaire if used in future research.

C-11 cyanide production system

Science.gov (United States)

Kim, Dohyun; Alexoff, David; Kim, Sung Won; Hooker, Jacob M.; Ferrieri, Richard A.

2017-11-21

A method for providing .sup.11C-labeled cyanides from .sup.11C labeled oxides in a target gas stream retrieved from an irradiated high pressure gaseous target containing O.sub.2, wherein .sup.11C labeled oxides are reduced with H.sub.2 in the presence of a nickel catalyst under a pressure and a temperature sufficient to form a product stream comprising at least about 95% .sup.11CH.sub.4, the .sup.11CH.sub.4 is then combined with an excess of NH.sub.3 in a carrier/reaction stream flowing at an accelerated velocity and the combined .sup.11CH4 carrier/reaction stream is then contacted with a platinum (Pt) catalyst particulate supported on a substantially-chemically-nonreactive heat-stable support at a temperature of at least about 900.degree. C., whereby a product stream comprising at least about 60% H.sup.11CN is provided in less than 10 minutes from retrieval of the .sup.11C labeled oxide.

Reliability of an incremental exercise test to evaluate acute blood lactate, heart rate and body temperature responses in Labrador retrievers.

Science.gov (United States)

Ferasin, Luca; Marcora, Samuele

2009-10-01

Thirteen healthy Labrador retrievers underwent a 5-stage incremental treadmill exercise test to assess its reliability. Blood lactate (BL), heart rate (HR), and body temperature (BT) were measured at rest, after each stage of exercise, and after a 20-min recovery. Reproducibility was assessed by repeating the test after 7 days. Two-way MANOVAs revealed significant differences between consecutive stages, and between values at rest and after recovery. There was also a significant reduction in physiological strain between the first and second trial (learning effect). Test reliability expressed as typical error (BL = 0.22 mmol/l, HR = 9.81 bpm, BT = 0.22 degrees C), coefficient of variation (BL = 19.3%, HR = 7.9% and BT = 0.6%) and test-retest correlation (BL = 0.89, HR = 0.96, BT = 0.95) was good. Results support test reproducibility although the learning effect needs to be controlled when investigating the exercise-related problems commonly observed in this breed.

Community Laboratory Testing for Cryptosporidium: Multicenter Study Retesting Public Health Surveillance Stool Samples Positive for Cryptosporidium by Rapid Cartridge Assay with Direct Fluorescent Antibody Testing.

Directory of Open Access Journals (Sweden)

Dawn M Roellig

Full Text Available Cryptosporidium is a common cause of sporadic diarrheal disease and outbreaks in the United States. Increasingly, immunochromatography-based rapid cartridge assays (RCAs are providing community laboratories with a quick cryptosporidiosis diagnostic method. In the current study, the Centers for Disease Control and Prevention (CDC, the Association of Public Health Laboratories (APHL, and four state health departments evaluated RCA-positive samples obtained during routine Cryptosporidium testing. All samples underwent "head to head" re-testing using both RCA and direct fluorescence assay (DFA. Community level results from three sites indicated that 54.4% (166/305 of Meridian ImmunoCard STAT! positives and 87.0% (67/77 of Remel Xpect positives were confirmed by DFA. When samples were retested by RCA at state laboratories and compared with DFA, 83.3% (155/186 of Meridian ImmunoCard STAT! positives and 95.2% (60/63 of Remel Xpect positives were confirmed. The percentage of confirmed community results varied by site: Minnesota, 39.0%; New York, 63.9%; and Wisconsin, 72.1%. The percentage of confirmed community results decreased with patient age; 12.5% of community positive tests could be confirmed by DFA for patients 60 years of age or older. The percentage of confirmed results did not differ significantly by sex, storage temperature, time between sample collection and testing, or season. Findings from this study demonstrate a lower confirmation rate of community RCA positives when compared to RCA positives identified at state laboratories. Elucidating the causes of decreased test performance in order to improve overall community laboratory performance of these tests is critical for understanding the epidemiology of cryptosporidiosis in the United States (US.

Cloning of cDNA encoding steroid 11β-hydroxylase (P450c11)

International Nuclear Information System (INIS)

Chua, S.C.; Szabo, P.; Vitek, A.; Grzeschik, K.H.; John, M.; White, P.C.

1987-01-01

The authors have isolated bovine and human adrenal cDNA clones encoding the adrenal cytochrome P-450 specific for 11β-hydroxylation (P450c11). A bovine adrenal cDNA library constructed in the bacteriophage λ vector gt10 was probed with a previously isolated cDNA clone corresponding to part of the 3' untranslated region of the 4.2-kilobase (kb) mRNA encoding P450c11. Several clones with 3.2-kb cDNA inserts were isolated. Sequence analysis showed that they overlapped the original probe by 300 base pairs (bp). Combined cDNA and RNA sequence data demonstrated a continuous open reading frame of 1509 bases. P450c11 is predicted to contain 479 amino acid residues in the mature protein in addition to a 24-residue amino-terminal mitochondrial signal sequence. A bovine clone was used to isolate a homologous clone with a 3.5-kb insert from a human adrenal cDNA library. A region of 1100 bp was 81% homologous to 769 bp of the coding sequence of the bovine cDNA except for a 400-bp segment presumed to be an unprocessed intron. Hybridization of the human cDNA to DNA from a panel of human-rodent somatic cell hybrid lines and in situ hybridization to metaphase spreads of human chromosomes localized the gene to the middle of the long arm of chromosome 8. These data should be useful in developing reagents for heterozygote detection and prenatal diagnosis of 11β-hydroxylase deficiency, the second most frequent cause of congenital adrenal hyperplasia

How reliable are the sup 14 C-urea breath test and specific serology for the detection of gastric campylobacter

Energy Technology Data Exchange (ETDEWEB)

Husebye, E; O' Leary, D; Skar, V; Melby, K [Ullevaal Sykehus, Oslo (Norway)

1990-01-01

Detection of gastric campylobacter by the {sup 14}C-urea breath test and serology were correlated to biopsy culture in 25 unselected outpatients referred for gastroscopy. All the 17 culture-positive patients had positive {sup 14}C-urea breath test, and 16 had positive serology. Of eight culture-negative patients, six patients had negative breath test and seven negative serology. A high degree of reproducibility was found when two subsequent breath tests were performed in 11 healthy volunteers. The breath test values obtained at 10 min showed a strong correlation to the accumulated values within 30 min. Breath sampling once, 10 min after intake of 2.5 {mu}Ci {sup 14}C-urea, seems sufficient for the detection of gastric campylobacter. The {sup 14}C-urea breath test correlates well with biopsy culture and provides a sensitive tool for the detection of gastric campylobacter. Serology also corresponds well with biopsy culture and should provide a useful tool for epidemiologic studies. 22 refs., 4 figs., 1 tab.

Preparation of [11C]diethyl oxalate and [11C]oxalic acid and demonstration of their use in the synthesis of [11C]-2,3-dihydroxyquinoxaline

International Nuclear Information System (INIS)

Thorell, J.-O.; Stone-Elander, S.

1993-01-01

A method for the production of two new carbon-11 labelled difunctional radiolabelling precursors, [ 11 C]diethyl oxalate,2, and [ 11 C]oxalic acid, 3 is described. Methyl chloroformate was reacted with no-carrier-added [ 11 C]cyanide to generate the intermediate nitrile, methyl [ 11 C]cyanoformate. Alcoholysis with HC1 in ethanol generated 2, which could subsequently be converted to 3 with aqueous acid. The total time of preparation from end-or-trapping of [ 11 C]cyanide was 6-7 min using combined microwave and thermal treatment or, by exclusively thermal treatment, 15 and 20 min for 2 and 3, respectively. The radiochemical conversion of [ 11 C]cyanide to 2 and 3 was ∼ 80% and ∼ 70%, respectively. Both 2 and 3 were used in a model reaction with 1,2-phenylenediamine to synthesize the heterocyclic compound, 2,3-dihydroxyquinoxaline, a basic structural unit in antagonists for the excitatory amino acid receptor system. (Author)

Retesting young STI clinic visitors with urogenital Chlamydia trachomatis infection in the Netherlands; response to a text message reminder and reinfection rates: a prospective study with historical controls.

Science.gov (United States)

Kampman, Cjg; Koedijk, Fdh; Driessen-Hulshof, Hcm; Hautvast, Jla; van den Broek, Ivf

2016-03-01

The objective of this study is to assess the effect of reminder text messages 6 months after the initial treatment on retest and chlamydia reinfection rates in young heterosexuals compared with a historical control group and to assess factors associated with both outcomes. Heterosexual people (aged 16-23 years), testing positive for urogenital chlamydia, were offered a retest after 6 months. Participants received a text message reminder at 6 months after the initial chlamydia diagnosis. Rates of retest uptake and the result of the retest were analysed using Cox regression. Prevalence ratios (PRs) were calculated to identify factors associated with these outcomes. Furthermore, the retest rate was compared with the retest rate of a historical control group. 30.6% (253/838) of the study group returned within 5-8 months compared with 9.2% (140/1530) in the historical control group. Women and persons who were not notified for a sexually transmitted infection (STI) at inclusion were more likely to return for a retest. 20.4% (56/275) of participants had a chlamydia reinfection upon retesting. Reinfection was higher in participants reporting STI-related symptoms (PR 3.2, 95% CI 1.8 to 5.6) and in participants who were notified for an STI at retest (PR 5.3, 95% CI 2.4 to 11.5). A text message reminder appeared to have a clear, positive impact on the resulting retest rate. These results also indicate that retesting is necessary to identify chlamydia reinfections. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Reproducibility of skeletal muscle vasodilatation responses to Stroop mental challenge over repeated sessions.

Science.gov (United States)

Hamer, Mark; Boutcher, Yati N; Park, Young; Boutcher, Stephen H

2006-08-01

Skeletal muscle blood flow responses to stress have implications for psychobiological disease pathways. An important assumption underlying psychophysiological studies relating stress reactivity with disease risk is that individuals are characterized by stable response profiles that can be reliably assessed using acute psychophysiological stress testing. We examined the reproducibility of forearm vasodilatation, blood pressure, and cardiac responses to a 2 min Stroop mental challenge over two repeated stress sessions that were on average 3.6 months apart. Participants were 21 healthy men and women (aged 21.8+/-3.7 years). Vasodilatation, blood pressure and heart rate responses displayed no habituation between sessions, although there was significantly greater cardiac parasympathetic involvement during the second testing session. Significant test-retest correlations between the sessions were observed for both forearm blood flow and heart rate reactivity. These findings demonstrate skeletal muscle vasodilatation responses to repeated stress are robust, so may be a useful psychophysiological indicator in studies of stress reactivity and disease risk.

Assessment of test-retest reliability and internal consistency of the Wisconsin Gait Scale in hemiparetic post-stroke patients

Directory of Open Access Journals (Sweden)

Guzik Agnieszka

2016-09-01

Full Text Available Introduction: A proper assessment of gait pattern is a significant aspect in planning the process of teaching gait in hemiparetic post-stroke patients. The Wisconsin Gait Scale (WGS is an observational tool for assessing post-stroke patients’ gait. The aim of the study was to assess test-retest reliability and internal consistency of the WGS and examine correlations between gait assessment made with the WGS and gait speed, Brunnström scale, Ashworth’s scale and the Barthel Index.

Test-retest reliability of an fMRI paradigm for studies of cardiovascular reactivity.

Science.gov (United States)

Sheu, Lei K; Jennings, J Richard; Gianaros, Peter J

2012-07-01

We examined the reliability of measures of fMRI, subjective, and cardiovascular reactions to standardized versions of a Stroop color-word task and a multisource interference task. A sample of 14 men and 12 women (30-49 years old) completed the tasks on two occasions, separated by a median of 88 days. The reliability of fMRI BOLD signal changes in brain areas engaged by the tasks was moderate, and aggregating fMRI BOLD signal changes across the tasks improved test-retest reliability metrics. These metrics included voxel-wise intraclass correlation coefficients (ICCs) and overlap ratio statistics. Task-aggregated ratings of subjective arousal, valence, and control, as well as cardiovascular reactions evoked by the tasks showed ICCs of 0.57 to 0.87 (ps reliability. These findings support using these tasks as a battery for fMRI studies of cardiovascular reactivity. Copyright © 2012 Society for Psychophysiological Research.

Validation and reproducibility of an Australian caffeine food frequency questionnaire.

Science.gov (United States)

Watson, E J; Kohler, M; Banks, S; Coates, A M

2017-08-01

The aim of this study was to measure validity and reproducibility of a caffeine food frequency questionnaire (C-FFQ) developed for the Australian population. The C-FFQ was designed to assess average daily caffeine consumption using four categories of food and beverages including; energy drinks; soft drinks/soda; coffee and tea and chocolate (food and drink). Participants completed a seven-day food diary immediately followed by the C-FFQ on two consecutive days. The questionnaire was first piloted in 20 adults, and then, a validity/reproducibility study was conducted (n = 90 adults). The C-FFQ showed moderate correlations (r = .60), fair agreement (mean difference 63 mg) and reasonable quintile rankings indicating fair to moderate agreement with the seven-day food diary. To test reproducibility, the C-FFQ was compared to itself and showed strong correlations (r = .90), good quintile rankings and strong kappa values (κ = 0.65), indicating strong reproducibility. The C-FFQ shows adequate validity and reproducibility and will aid researchers in Australia to quantify caffeine consumption.

Internal consistency, reliability, and temporal stability of the Oxford Happiness Questionnaire short-form: Test-retest data over two weeks

OpenAIRE

MCGUCKIN, CONOR

2006-01-01

PUBLISHED The Oxford Happiness Questionnaire short-form is a recently developed eight-item measure of happiness. This study evaluated the internal consistency reliability and test-retest reliability of the Oxford Happiness Questionnaire short-form among 55 Northern Irish undergraduate university students who completed the measure on two occasions separated by two weeks. Internal consistency of the measure on both occasions was satisfactory at both Time 1 (alpha = .62) and Time 2 (alpha = ....

Impact of Alzheimer's Disease on Caregiver Questionnaire: internal consistency, convergent validity, and test-retest reliability of a new measure for assessing caregiver burden.

Science.gov (United States)

Cole, Jason C; Ito, Diane; Chen, Yaozhu J; Cheng, Rebecca; Bolognese, Jennifer; Li-McLeod, Josephine

2014-09-04

There is a lack of validated instruments to measure the level of burden of Alzheimer's disease (AD) on caregivers. The Impact of Alzheimer's Disease on Caregiver Questionnaire (IADCQ) is a 12-item instrument with a seven-day recall period that measures AD caregiver's burden across emotional, physical, social, financial, sleep, and time aspects. Primary objectives of this study were to evaluate psychometric properties of IADCQ administered on the Web and to determine most appropriate scoring algorithm. A national sample of 200 unpaid AD caregivers participated in this study by completing the Web-based version of IADCQ and Short Form-12 Health Survey Version 2 (SF-12v2™). The SF-12v2 was used to measure convergent validity of IADCQ scores and to provide an understanding of the overall health-related quality of life of sampled AD caregivers. The IADCQ survey was also completed four weeks later by a randomly selected subgroup of 50 participants to assess test-retest reliability. Confirmatory factor analysis (CFA) was implemented to test the dimensionality of the IADCQ items. Classical item-level and scale-level psychometric analyses were conducted to estimate psychometric characteristics of the instrument. Test-retest reliability was performed to evaluate the instrument's stability and consistency over time. Virtually none (2%) of the respondents had either floor or ceiling effects, indicating the IADCQ covers an ideal range of burden. A single-factor model obtained appropriate goodness of fit and provided evidence that a simple sum score of the 12 items of IADCQ can be used to measure AD caregiver's burden. Scales-level reliability was supported with a coefficient alpha of 0.93 and an intra-class correlation coefficient (for test-retest reliability) of 0.68 (95% CI: 0.50-0.80). Low-moderate negative correlations were observed between the IADCQ and scales of the SF-12v2. The study findings suggest the IADCQ has appropriate psychometric characteristics as a

Improved sensitivity of human brain MAO B measurement using deuterium substituted [{sup 11}C]L-deprenyl ([{sup 11}C]L-deprenyl-D2)

Energy Technology Data Exchange (ETDEWEB)

Fowler, J.S.; Volkow, N.D.; Wang, G.J. [Brookhaven National Laboratory, Upton, NY (United States)] [and others

1995-05-01

Post-mortem reports that human brain monoamine oxidase B (MAO B) increases in normal aging and neurodegenerative disorders due to the proliferation of MAO B-rich glial cells suggest that PET measures of MAO B may track gliosis. We have recently shown that the MAO B tracer [{sup 11}C]L-deprenyl has limited sensitivity in regions of high MAO B due to its rapid rate of trapping. This limits its utility for measuring MAO B in brain regions where MAO B is higher and/or where blood flow is low. We have recently demonstrated that [{sup 11}C]L-deprenyl-D2 has improved sensitivity in regions of high MAO B due to the deuterium isotope effect which reduces the rate of trapping. We report studies [{sup 11}C]L-deprenyl-D2 in normal human brain in 16 healthy men and women (age range 23-73) to assess tracer sensitivity, regional distribution, and reproducibility. Graphical analysis for irreversible systems was used to calculate Ki (influx constant) as an index of MAO B concentration in different brain regions. The uptake of carbon-11 in different brain regions was rapid, peaking at 5 minutes and plateauing from 30-60 minutes after an initial clearance. MAO B was highest in subcortical regions: thalamus{ge}basal ganglia>cingulate gyrus>frontal cortex=occipital cortex=cerebellum in agreement with post-mortem measurements. Ki values were highly correlated within an individual. Repeated measures at 1-4 week intervals were highly correlated (r=0.9; p=0.0001). In women (n=8: age range 23-73), Ki increased with increasing age for 8 brain regions (p < 0.04). Though men (N=8; age range 34-70) showed no correlation with age, a larger sample size is needed to adequately assess trends. In summary, the use of [{sup 11}C]L-deprenyl-D2 improves the measurement of MAO B in the human brain permitting its investigation as a positive tracer for glial cell proliferation in neurodegenerative disorders.

Repeatability and reproducibility of decisions by latent fingerprint examiners.

Directory of Open Access Journals (Sweden)

Bradford T Ulery

Full Text Available The interpretation of forensic fingerprint evidence relies on the expertise of latent print examiners. We tested latent print examiners on the extent to which they reached consistent decisions. This study assessed intra-examiner repeatability by retesting 72 examiners on comparisons of latent and exemplar fingerprints, after an interval of approximately seven months; each examiner was reassigned 25 image pairs for comparison, out of total pool of 744 image pairs. We compare these repeatability results with reproducibility (inter-examiner results derived from our previous study. Examiners repeated 89.1% of their individualization decisions, and 90.1% of their exclusion decisions; most of the changed decisions resulted in inconclusive decisions. Repeatability of comparison decisions (individualization, exclusion, inconclusive was 90.0% for mated pairs, and 85.9% for nonmated pairs. Repeatability and reproducibility were notably lower for comparisons assessed by the examiners as "difficult" than for "easy" or "moderate" comparisons, indicating that examiners' assessments of difficulty may be useful for quality assurance. No false positive errors were repeated (n = 4; 30% of false negative errors were repeated. One percent of latent value decisions were completely reversed (no value even for exclusion vs. of value for individualization. Most of the inter- and intra-examiner variability concerned whether the examiners considered the information available to be sufficient to reach a conclusion; this variability was concentrated on specific image pairs such that repeatability and reproducibility were very high on some comparisons and very low on others. Much of the variability appears to be due to making categorical decisions in borderline cases.

11C-MET PET/MRI for detection of recurrent glioma.

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Deuschl, C; Kirchner, J; Poeppel, T D; Schaarschmidt, B; Kebir, S; El Hindy, N; Hense, J; Quick, H H; Glas, M; Herrmann, K; Umutlu, L; Moenninghoff, C; Radbruch, A; Forsting, M; Schlamann, M

2018-04-01

Radiological assessment of brain tumors is widely based on the Radiology Assessment of Neuro-Oncology (RANO) criteria that consider non-specific T1 and T2 weighted images. Limitation of the RANO criteria is that they do not include metabolic imaging techniques that have been reported to be helpful to differentiate treatment related changes from true tumor progression. In the current study, we assessed if the combined use of MRI and PET with hybrid 11 C-MET PET/MRI can improve diagnostic accuracy and diagnostic confidence of the readers to differentiate treatment related changes from true progression in recurrent glioma. Fifty consecutive patients with histopathologically proven glioma were prospectively enrolled for a hybrid 11 C-MET PET/MRI to differentiate recurrent glioma from treatment induced changes. Sole MRI data were analyzed based on RANO. Sole PET data and in a third evaluation hybrid 11 C-MET-PET/MRI data were assessed for metabolic respectively metabolic and morphologic glioma recurrence. Diagnostic performance and diagnostic confidence of the reader were calculated for the different modalities, and the McNemar test and Mann-Whitney U Test were applied for statistical analysis. Hybrid 11 C-MET PET/MRI was successfully performed in all 50 patients. Glioma recurrence was diagnosed in 35 of the 50 patients (70%). Sensitivity and specificity were calculated for MRI (86.11% and 71.43%), for 11 C-MET PET (96.77% and 73.68%), and for hybrid 11 C-MET-PET/MRI (97.14% and 93.33%). For diagnostic accuracy hybrid 11 C-MET-PET/MRI (96%) showed significantly higher values than MRI alone (82%), whereas no significant difference was found for 11C-MET PET (88%). Furthermore, by rating on a five-point Likert scale significantly higher scores were found for diagnostic confidence when comparing 11 C-MET PET/MRI (4.26 ± 0,777) to either PET alone (3.44 ± 0.705) or MRI alone (3.56 ± 0.733). This feasibility study showed that hybrid PET/MRI might strengthen

14 CFR 65.19 - Retesting after failure.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Retesting after failure. 65.19 Section 65.19 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS General § 65.19 Retesting after failure. An...

Radiosynthesis of the D2/3 agonist [3-11C]-(+)-PHNO using [11C]iodomethane

International Nuclear Information System (INIS)

Francisco Garcia-Arguello, Segundo; Fortt, Robin; Steel, Colin J.; Brickute, Diana; Glaser, Matthias; Turton, David R.; Robins, Edward G.; Årstad, Erik; Luthra, Sajinder K.

2013-01-01

We report here a radiosynthesis for the D 2/3 agonist (+)-4-([3- 11 C]propyl)-3,4,4a,5,6,10b-hexahydro-2H-naphtho[1,2-b][1,4] oxazin-9-ol (3-[ 11 C]-(+)-PHNO) labelled at the terminal carbon of the N-propyl chain. The protocol is based on 11 C-methylation of an N-acetyl precursor. This initial step is followed by a reduction with LiAlH 4 to give ([3- 11 C]-(+)-PHNO). We first applied the method for the synthesis of a model compound, N-3-([ 11 C]propyl)-1,2,3,4-tetrahydroisoquinoline, which we obtained in 77–97% analytical radiochemical yield (n=6) in 20 min. Similarly, we prepared ([3- 11 C]-(+)-PHNO) in 55–60% analytical radiochemical yield (n=5) using a one-pot procedure. We have also been able to implement the complete process on a semi-automated module. This platform delivered purified and formulated [3- 11 C]PHNO with an average radiochemical yield of 9% (n=13, range 2–30%, non-decay corrected), a radiochemical purity >95%, and a specific radioactivity of 26.8–81.1 GBq/μmol in a total time of 63–65 min. - Highlights: ► We report an alternative method to obtain carbon-11 labelled PHNO. ► The method is based on readily available [ 11 C]methyl iodide as starting material. ► We have automated the alkylation/reduction protocol including purification and formulation

Blink frequency and duration during perimetry and their relationship to test-retest threshold variability.

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Wang, Yanfang; Toor, Sonia S; Gautam, Ramesh; Henson, David B

2011-06-28

To describe different patterns of blinking in patients undergoing a visual field test and to establish whether the blink parameters are related to threshold variability. Thirty-nine patients with diagnosed or suspected glaucoma were recruited to undertake a perimetric task twice. Blinks were detected with a video eye-tracker system that records at a sampling rate of 60 Hz. Blink frequency, duration, and episodes of microsleep (eye closures >500 ms) were analyzed, and correlated with test-retest threshold variability. The timing of blinks with respect to stimulus presentation was analyzed and the percentage of seen stimuli for all presentations (POS(overall)) and those overlapped with blinks (POS(overlapped)) were compared. Blink frequency ranged from 0 to 58 per minute. A significant increase in blink frequency was observed in the second test (P POS(overall) and POS(overlapped) was significant (P POS(overlapped) was observed with the increase of overlap duration. A wide range of blink frequencies was observed during perimetric testing. Although no blink parameters showed significant influence on threshold variability, when the blinks overlapped with a stimulus presentation, the probability of seeing was reduced. For suprathreshold stimuli, blinks often occurred after the presentation, whereas for subthreshold presentations, there was no relationship to presentation time.

Synthesis of some 11C-labelled alkaloids

International Nuclear Information System (INIS)

Laangstroem, B.; Antoni, G.; Halldin, H.; Svaerd, H.; Bergson, G.

1982-01-01

Using ( 11 C)-methyl iodide in N-alkylation reactions in dimethylformamide (DMF), the alkaloids N-( 11 C-methyl)-morphine, N-( 11 C-methyl)-codeine, 6-N(methyl)-9, 10-dihydroergotamine, 6-N-( 11 C-methyl)-bromocriptine and N-( 11 C-methyl)-nicotine have been synthesized in radiochemical yields of 50-95%, within 5-10 min of introducing ( 11 C)-methyl iodide into the reaction vial. ( 11 C)-Methyl iodide was obtained within 4-7 min from ( 11 C)-carbon dioxide prepared by the 14 N(p,α) 11 C reaction. (Authors)

Evaluation of the Relative Validity and Test-Retest Reliability of a 15-Item Beverage Intake Questionnaire in Children and Adolescents.

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Hill, Catelyn E; MacDougall, Carly R; Riebl, Shaun K; Savla, Jyoti; Hedrick, Valisa E; Davy, Brenda M

2017-11-01

Added sugar intake, in the form of sugar-sweetened beverages (SSBs), may contribute to weight gain and obesity development in children and adolescents. A valid and reliable brief beverage intake assessment tool for children and adolescents could facilitate research in this area. The purpose of this investigation was to evaluate the relative validity and test-retest reliability of a 15-item beverage intake questionnaire (BEVQ) for assessing usual beverage intake in children and adolescents. This cross-sectional investigation included four study visits within a 2- to 3-week time period. Participants (333 enrolled; 98% completion rate) were children aged 6 to 11 years and adolescents aged 12 to18 years recruited from the New River Valley, VA, region from January 2014 to September 2015. Study visits included assessment of height/weight, health history, and four 24-hour dietary recalls (24HRs). The BEVQ was completed at two visits (BEVQ 1, BEVQ 2). To evaluate relative validity, BEVQ 1 was compared with habitual beverage intake determined by the averaged 24HR. To evaluate test-retest reliability, BEVQ 1 was compared with BEVQ 2. Analyses included descriptive statistics, independent sample t tests, χ 2 tests, one-way analysis of variance, paired sample t tests, and correlational analyses. In the full sample, self-reported water and total SSB intake were not different between BEVQ 1 and 24HR (mean differences 0±1 fl oz and 0±1 fl oz, respectively; both P values >0.05). Reported intake across all beverage categories was significantly correlated between BEVQ 1 and BEVQ 2 (Pbeverages was not different (all P values >0.05) between BEVQ 1 and 24HR (mean differences: whole milk=3±4 kcal, reduced-fat milk=9±5 kcal, and fat-free milk=7±6 kcal, which is 7±15 total beverage kilocalories). In adolescents (n=200), water and SSB kilocalories were not different (both P values >0.05) between BEVQ 1 and 24HR (mean differences: -1±1 fl oz and 12±9 kcal, respectively). A 15

C-11 production with MC-50 cyclotron and synthesis of L-[11C-methyl] methionine

International Nuclear Information System (INIS)

Kim, Sang Wook; Hur, Min Goo; Yang, Seung Dae; Ahn, Soon Hyuk; Chun, Kweon Soo

2003-01-01

L-[ 11 C-methyl] methionine was prepared via no-carrier-added(nca) fast S-alkylation of L-homocysteine with [ 11 C]CH 3 I using solid support (Al 2 O 3 /KF)at room temperature in ethanol. The radiochemical yield of methylation was 90.2%. After reaction, no radiochemical impurity was detected but traces of L-homocysteine precursor were monitored by UV detector. The purification was archived by passing successively through a C 18 and alumina sep-pak. the radiochemical purity of L-[ 11 C-methyl] methionine was over 98% after purification and total elapsed time to prepare was 10min from [ 11 C]CH 3 I delivery

11 CFR 100.131 - Testing the waters.

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2010-01-01

... 11 Federal Elections 1 2010-01-01 2010-01-01 false Testing the waters. 100.131 Section 100.131 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) Exceptions to Expenditures § 100.131 Testing the waters. (a) General exemption. Payments made solely for the purpose of...

11 CFR 100.72 - Testing the waters.

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2010-01-01

... 11 Federal Elections 1 2010-01-01 2010-01-01 false Testing the waters. 100.72 Section 100.72 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) Exceptions to Contributions § 100.72 Testing the waters. (a) General exemption. Funds received solely for the purpose of...

How reproducible is self-reported information on exposure to smoking, drinking, and dietary patterns? Evidence among Brazilian adults in the Pró-Saúde Study

Directory of Open Access Journals (Sweden)

Dóra Chor

Full Text Available CONTEXT: Epidemiological studies of the validity and reliability of self-reported information on important risk factors for non-communicable chronic diseases are scarce in Brazil. OBJECTIVE: We evaluated the test-retest reliability of information overall and stratified by gender, age and education on active and passive smoking, alcohol intake and aspects of dietary habits. TYPE OF STUDY: Test-retest reliability. SETTING: Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil. PARTICIPANTS: 192 University employees. PROCEDURES: Self-administered questionnaires were completed on two occasions, two weeks apart. MAIN MEASUREMENTS: Kappa Statistics; Intraclass Correlation Coefficient. RESULTS: Information on smoking status and pack-years smoked had almost perfect levels of agreement, respectively, kappa = 0.97 (95% CI, 0.92-1.00, and intraclass correlation coefficient = 0.93 (CI 95%, 0.89-0.96. Characteristics of alcohol intake yielded substantial levels of agreement (kappa ranging from 0.62 to 0.69. The reproducibility of the information on dietary habits varied from 0.67 to 0.79 (kappa. No clear-cut patterns could be identified comparing information by age or gender. There was a slight tendency towards greater reliability among people with higher levels of education. CONCLUSION: The reproducibility of information on smoking, drinking, and dietary patterns ranged from substantial to excellent, as investigated in the Pró-Saúde Study, a longitudinal investigation recently launched in Rio de Janeiro.

Reliability and validity of a questionnaire to measure personal, social and environmental correlates of fruit and vegetable intake in 10-11-year-old children in five European countries

DEFF Research Database (Denmark)

De Bourdeaudhuij, I; Klepp, K-I; Due, P

2005-01-01

To investigate the internal consistency of the scales and the test-retest reliability and predictive validity of behaviour theory-based constructs measuring personal, social and environmental correlates of fruit and vegetable intake in 10-11-year-old children.......To investigate the internal consistency of the scales and the test-retest reliability and predictive validity of behaviour theory-based constructs measuring personal, social and environmental correlates of fruit and vegetable intake in 10-11-year-old children....

Carbon-11 labelling of an inhibitor of acetylcholinesterase: [11C]physostigmine

International Nuclear Information System (INIS)

Bonnot-Lours, S.; Crouzel, C.; Prenant, C.; Hinnen, F.

1993-01-01

Physostigmine, an alkaloid from calabar bean is a strong inhibitor of acetylcholinesterase and has been used clinically in the treatment of glaucoma, atropine intoxication, myasthenia gravis and more recently, in experimental trials in Alzheimer's disease. In order to study the AChE activity in the brain by positron emission tomography, we have undertaken the labelling of physostigmine with carbon-11. The synthesis involves the reaction of [ 11 C]methylisocyanate with eseroline. [ 11 C]Methylisocyanate was obtained by heating [ 11 C]acetylchloride with tetrabutylammonium azide in toluene. The synthesis of [ 11 C]CH 3 COC1 involves the carbonation of methylmagnesium bromide in THF with cyclotron produced [ 11 C]carbon dioxide and the addition of phthaloyl dichloride. The [ 11 C]methylisocyanate is distilled into a solution of eseroline in ether with a small piece of sodium. After 10 minutes at 25 o C, the solution is purified by HPLC and the appropriate fraction collected. Starting with 55.5 GBq (1.5 Ci) of [ 11 C]carbon dioxide, 0.92-1.48 GBq (25-40 mCi) of [ 11 C]Physostigmine are obtained 57 minutes after EOB. (author)

Test-retest reliability of behavioral measures of impulsive choice, impulsive action, and inattention.

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Weafer, Jessica; Baggott, Matthew J; de Wit, Harriet

2013-12-01

Behavioral measures of impulsivity are widely used in substance abuse research, yet relatively little attention has been devoted to establishing their psychometric properties, especially their reliability over repeated administration. The current study examined the test-retest reliability of a battery of standardized behavioral impulsivity tasks, including measures of impulsive choice (i.e., delay discounting, probability discounting, and the Balloon Analogue Risk Task), impulsive action (i.e., the stop signal task, the go/no-go task, and commission errors on the continuous performance task), and inattention (i.e., attention lapses on a simple reaction time task and omission errors on the continuous performance task). Healthy adults (n = 128) performed the battery on two separate occasions. Reliability estimates for the individual tasks ranged from moderate to high, with Pearson correlations within the specific impulsivity domains as follows: impulsive choice (r range: .76-.89, ps reliable measures and thus can be confidently used to assess various facets of impulsivity as intermediate phenotypes for drug abuse.

Reproducibility of up-flow column percolation tests for contaminated soils.

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Tetsuo Yasutaka

Full Text Available Up-flow column percolation tests are used at laboratory scale to assess the leaching behavior of hazardous substance from contaminated soils in a specific condition as a function of time. Monitoring the quality of these test results inter or within laboratory is crucial, especially if used for Environment-related legal policy or for routine testing purposes. We tested three different sandy loam type soils (Soils I, II and III to determine the reproducibility (variability inter laboratory of test results and to evaluate the difference in the test results within laboratory. Up-flow column percolation tests were performed following the procedure described in the ISO/TS 21268-3. This procedure consists of percolating solution (calcium chloride 1 mM from bottom to top at a flow rate of 12 mL/h through softly compacted soil contained in a column of 5 cm diameter and 30 ± 5 cm height. Eluate samples were collected at liquid-to-solid ratio of 0.1, 0.2, 0.5, 1, 2, 5 and 10 L/kg and analyzed for quantification of the target elements (Cu, As, Se, Cl, Ca, F, Mg, DOC and B in this research. For Soil I, 17 institutions in Japan joined this validation test. The up-flow column experiments were conducted in duplicate, after 48 h of equilibration time and at a flow rate of 12 mL/h. Column percolation test results from Soils II and III were used to evaluate the difference in test results from the experiments conducted in duplicate in a single laboratory, after 16 h of equilibration time and at a flow rate of 36 mL/h. Overall results showed good reproducibility (expressed in terms of the coefficient of variation, CV, calculated by dividing the standard deviation by the mean, as the CV was lower than 30% in more than 90% of the test results associated with Soil I. Moreover, low variability (expressed in terms of difference between the two test results divided by the mean was observed in the test results related to Soils II and III, with a variability lower than 30

Synthesis of O-[11C]acetyl CoA, O-[11C]acetyl-L-carnitine, and L-[11C]carnitine labelled in specific positions, applied in PET studies on rhesus monkey

International Nuclear Information System (INIS)

Jacobson, Gunilla B.; Watanabe, Yasuyoshi; Valind, Sven; Kuratsune, Hirohiko; Laangstroem, Bengt

1997-01-01

The syntheses of L-carnitine, O-acetyl CoA, and O-acetyl-L-carnitine labelled with 11 C at the 1- or 2-position of the acetyl group or the N-methyl position of carnitine, using the enzymes acetyl CoA synthetase and carnitine acetyltransferase, are described. With a total synthesis time of 45 min, O-[1- 11 C]acetyl CoA and O-[2- 11 C]acetyl CoA was obtained in 60-70% decay-corrected radiochemical yield, and O-[1- 11 C]acetyl-L-carnitine and O-[2- 11 C]acetyl-L-carnitine in 70-80% yield, based on [1- 11 C]acetate or [2- 11 C]acetate, respectively. By an N-methylation reaction with [ 11 C]methyl iodide, L-[methyl- 11 C]carnitine was obtained within 30 min, and O-acetyl-L-[methyl- 11 C]carnitine within 40 min, giving a decay-corrected radiochemical yield of 60% and 40-50%, respectively, based on [ 11 C]methyl iodide. Initial data of the kinetics of the different 11 C-labelled L-carnitine and acetyl-L-carnitines in renal cortex of anaesthetized monkey (Macaca mulatta) are presented

Escala Razões para Fumar Modificada: tradução e adaptação cultural para o português para uso no Brasil e avaliação da confiabilidade teste-reteste Modified Reasons for Smoking Scale: translation to Portuguese, cross-cultural adaptation for use in Brazil and evaluation of test-retest reliability