scholarly journals Connectome-Based Smoothing (CBS): Concepts, methods, and evaluation

2021 ◽  
Author(s):  
Sina Mansour L. ◽  
Caio Seguin ◽  
Robert E Smith ◽  
Andrew Zalesky
Keyword(s):  
High Resolution ◽  
Statistical Power ◽  
Connectivity Matrix ◽  
Probabilistic Tractography ◽  
Spatial Smoothing ◽  
Computationally Efficient ◽  
Retest Reliability ◽  
Smoothing Kernel ◽  
Efficient Integration ◽  
Test Retest Reliability

Structural connectomes are increasingly mapped at high spatial resolutions comprising many hundreds—if not thousands—of network nodes. However, high-resolution connectomes are particularly susceptible to image registration misalignment, tractography artifacts, and noise, all of which can lead to reductions in connectome accuracy and test-retest reliability. We investigate a network analogue of image smoothing to address these key challenges. Connectome-Based Smoothing (CBS) involves jointly applying a carefully chosen smoothing kernel to the two endpoints of each tractography streamline, yielding a spatially smoothed connectivity matrix. We develop computationally efficient methods to perform CBS using a matrix congruence transformation and evaluate a range of different smoothing kernel choices on CBS performance. We find that smoothing substantially improves the identifiability, sensitivity, and test-retest reliability of high-resolution connectivity maps, though at a cost of increasing storage burden. For atlas-based connectomes (i.e. low-resolution connectivity maps), we show that CBS marginally improves the statistical power to detect associations between connectivity and cognitive performance, particularly for connectomes mapped using probabilistic tractography. CBS was also found to enable more reliable statistical inference compared to connectomes without any smoothing. We provide recommendations on optimal smoothing kernel parameters for connectomes mapped using both deterministic and probabilistic tractography. We conclude that spatial smoothing is particularly important for the reliability of high-resolution connectomes, but can also provide benefits at lower parcellation resolutions. We hope that our work enables computationally efficient integration of spatial smoothing into established structural connectome mapping pipelines.

scholarly journals Long-Term Test–Retest Reliability of Striatal and Extrastriatal Dopamine D2/3 Receptor Binding: Study with [11C]Raclopride and High-Resolution PET

2015 ◽  
Vol 35 (7) ◽  
pp. 1199-1205 ◽  
Author(s):  
Kati Alakurtti ◽  
Jarkko J Johansson ◽  
Juho Joutsa ◽  
Matti Laine ◽  
Lars Bäckman ◽  
...  
Keyword(s):  
High Resolution ◽  
Intraclass Correlation ◽  
Binding Potential ◽  
Reference Tissue ◽  
Retest Reliability ◽  
Positron Emission ◽  
Simplified Reference Tissue Model ◽  
Test Retest Reliability

We measured the long-term test–retest reliability of [11C]raclopride binding in striatal subregions, the thalamus and the cortex using the bolus-plus-infusion method and a high-resolution positron emission scanner. Seven healthy male volunteers underwent two positron emission tomography (PET) [11C]raclopride assessments, with a 5-week retest interval. D2/3 receptor availability was quantified as binding potential using the simplified reference tissue model. Absolute variability (VAR) and intraclass correlation coefficient (ICC) values indicated very good reproducibility for the striatum and were 4.5%/0.82, 3.9%/0.83, and 3.9%/0.82, for the caudate nucleus, putamen, and ventral striatum, respectively. Thalamic reliability was also very good, with VAR of 3.7% and ICC of 0.92. Test-retest data for cortical areas showed good to moderate reproducibility (6.1% to 13.1%). Our results are in line with previous test–retest studies of [11C]raclopride binding in the striatum. A novel finding is the relatively low variability of [11C]raclopride binding, providing suggestive evidence that extrastriatal D2/3 binding can be studied in vivo with [11C]raclopride PET to be verified in future studies.

scholarly journals The Reliability of Pharyngeal High Resolution Manometry with Impedance for Derivation of Measures of Swallowing Function in Healthy Volunteers

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Taher I. Omari ◽  
Johanna Savilampi ◽  
Karmen Kokkinn ◽  
Mistyka Schar ◽  
Kristin Lamvik ◽  
...  
Keyword(s):  
High Resolution ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Interrater Agreement ◽  
Swallowing Function ◽  
Retest Reliability ◽  
High Resolution Manometry ◽  
Intraclass Correlation Coefficients ◽  
Test Retest Reliability ◽  
Swallow Function

Purpose. We evaluated the intra- and interrater agreement and test-retest reliability of analyst derivation of swallow function variables based on repeated high resolution manometry with impedance measurements.Methods. Five subjects swallowed10×10 mL saline on two occasions one week apart producing a database of 100 swallows. Swallows were repeat-analysed by six observers using software. Swallow variables were indicative of contractility, intrabolus pressure, and flow timing.Results. The average intraclass correlation coefficients (ICC) for intra- and interrater comparisons of all variable means showedsubstantialtoexcellentagreement (intrarater ICC 0.85–1.00; mean interrater ICC 0.77–1.00). Test-retest results were less reliable. ICC for test-retest comparisons ranged fromslighttoexcellentdepending on the class of variable. Contractility variables differed most in terms of test-retest reliability. Amongst contractility variables, UES basal pressure showedexcellenttest-retest agreement (mean ICC 0.94), measures of UES postrelaxation contractile pressure showedmoderatetosubstantialtest-retest agreement (mean Interrater ICC 0.47–0.67), and test-retest agreement of pharyngeal contractile pressure ranged fromslighttosubstantial(mean Interrater ICC 0.15–0.61).Conclusions. Test-retest reliability of HRIM measures depends on the class of variable. Measures of bolus distension pressure and flow timing appear to be more test-retest reliable than measures of contractility.

scholarly journals Test-Retest Reliability of Graph Metrics in High-resolution Functional Connectomics: A Resting-State Functional MRI Study

2015 ◽  
Vol 21 (10) ◽  
pp. 802-816 ◽  
Author(s):  
Hai-Xiao Du ◽  
Xu-Hong Liao ◽  
Qi-Xiang Lin ◽  
Gu-Shu Li ◽  
Yu-Ze Chi ◽  
...  
Keyword(s):  
High Resolution ◽  
Functional Mri ◽  
Resting State ◽  
Retest Reliability ◽  
Graph Metrics ◽  
Mri Study ◽  
Test Retest Reliability

Measuring “Language Access Profiles” in Deaf and Hard-of-Hearing Children With the DHH Language Exposure Assessment Tool

2020 ◽  
pp. 1-25
Author(s):  
Matthew L. Hall ◽  
Stephanie De Anda
Keyword(s):  
Cluster Analysis ◽  
Exposure Assessment ◽  
Hard Of Hearing ◽  
Assessment Tool ◽  
Communication Mode ◽  
Developmental Potential ◽  
Language Access ◽  
Retest Reliability ◽  
Language Exposure ◽  
Test Retest Reliability

Purpose The purposes of this study were (a) to introduce “language access profiles” as a viable alternative construct to “communication mode” for describing experience with language input during early childhood for deaf and hard-of-hearing (DHH) children; (b) to describe the development of a new tool for measuring DHH children's language access profiles during infancy and toddlerhood; and (c) to evaluate the novelty, reliability, and validity of this tool. Method We adapted an existing retrospective parent report measure of early language experience (the Language Exposure Assessment Tool) to make it suitable for use with DHH populations. We administered the adapted instrument (DHH Language Exposure Assessment Tool [D-LEAT]) to the caregivers of 105 DHH children aged 12 years and younger. To measure convergent validity, we also administered another novel instrument: the Language Access Profile Tool. To measure test–retest reliability, half of the participants were interviewed again after 1 month. We identified groups of children with similar language access profiles by using hierarchical cluster analysis. Results The D-LEAT revealed DHH children's diverse experiences with access to language during infancy and toddlerhood. Cluster analysis groupings were markedly different from those derived from more traditional grouping rules (e.g., communication modes). Test–retest reliability was good, especially for the same-interviewer condition. Content, convergent, and face validity were strong. Conclusions To optimize DHH children's developmental potential, stakeholders who work at the individual and population levels would benefit from replacing communication mode with language access profiles. The D-LEAT is the first tool that aims to measure this novel construct. Despite limitations that future work aims to address, the present results demonstrate that the D-LEAT represents progress over the status quo.

Visual-Neural Correlate of Speechreading Ability in Normal-Hearing Adults

1982 ◽  
Vol 25 (4) ◽  
pp. 521-527 ◽  
Author(s):  
David C. Shepherd
Keyword(s):  
Normal Hearing ◽  
Wave Form ◽  
Firing Time ◽  
Neural Firing ◽  
Neural Correlate ◽  
Retest Reliability ◽  
Repeated Word ◽  
Negative Peak ◽  
The Stability ◽  
Test Retest Reliability

In 1977, Shepherd and colleagues reported significant correlations (–.90, –.91) between speechreading scores and the latency of a selected negative peak (VN 130 measure) on the averaged visual electroencephalic wave form. The primary purpose of this current study was to examine the stability, or repeatability, of this relation between these cognitive and neurophysiologic measures over a period of several months and thus support its test-retest reliability. Repeated speechreading word and sentence scores were gathered during three test-retest sessions from each of 20 normal-hearing adults. An average of 56 days occurred from the end of one to the beginning of another speechreading sessions. During each of four other test-retest sessions, averaged visual electroencephalic responses (AVER s ) were evoked from each subject. An average of 49 clays intervened between AVER sessions. Product-moment correlations computed among repeated word scores and VN l30 measures ranged from –.61 to –.89. Based on these findings, it was concluded that the VN l30 measure of visual neural firing time is a reliable correlate of speech-reading in normal-hearing adults.

Test-Retest Reliability of a Self-Report Questionnaire for DSM-IV and ICD-10 Personality Disorders

2000 ◽  
Vol 16 (1) ◽  
pp. 53-58 ◽  
Author(s):  
Hans Ottosson ◽  
Martin Grann ◽  
Gunnar Kullgren
Keyword(s):  
Personality Disorder ◽  
Anxiety Disorders ◽  
Personality Disorders ◽  
Clinical Sample ◽  
Self Report ◽  
Anxiety State ◽  
Short Term ◽  
Retest Reliability ◽  
Axis I ◽  
Test Retest Reliability

Summary: Short-term stability or test-retest reliability of self-reported personality traits is likely to be biased if the respondent is affected by a depressive or anxiety state. However, in some studies, DSM-oriented self-reported instruments have proved to be reasonably stable in the short term, regardless of co-occurring depressive or anxiety disorders. In the present study, we examined the short-term test-retest reliability of a new self-report questionnaire for personality disorder diagnosis (DIP-Q) on a clinical sample of 30 individuals, having either a depressive, an anxiety, or no axis-I disorder. Test-retest scorings from subjects with depressive disorders were mostly unstable, with a significant change in fulfilled criteria between entry and retest for three out of ten personality disorders: borderline, avoidant and obsessive-compulsive personality disorder. Scorings from subjects with anxiety disorders were unstable only for cluster C and dependent personality disorder items. In the absence of co-morbid depressive or anxiety disorders, mean dimensional scores of DIP-Q showed no significant differences between entry and retest. Overall, the effect from state on trait scorings was moderate, and it is concluded that test-retest reliability for DIP-Q is acceptable.

The Psychometrics of Three Dissociation Scales: Test-Retest, Reliability, and Relationship to Trauma

2013 ◽  
Author(s):  
Kristen M. Dahlin-James ◽  
Emily J. Hennrich ◽  
E. Grace Verbeck-Priest ◽  
Jan E. Estrellado ◽  
Jessica M. Stevens ◽  
...  
Keyword(s):  
Retest Reliability ◽  
Test Retest Reliability
Sign in / Sign up

Export Citation Format

Share Document