scholarly journals Short-term test-retest reliability of the human intrinsic functional connectome

2019 ◽  
Author(s):  
Leonardo Tozzi ◽  
Scott L. Fleming ◽  
Zachary D. Taylor ◽  
Cooper D. Raterink ◽  
Leanne M. Williams

ABSTRACTFunctional connectivity is frequently used to quantify the complex synchronous distributed fluctuations in neuronal activity derived from functional Magnetic Resonance Imaging and to generate network representations of human brain function. Such “functional connectomes” have great promise for mechanistic studies and for clinical translation. However, we do not know to what extent a functional connectome is stable over time for an individual. In the present work, we evaluate the short-term test-retest reliability of functional connectomes in a large publicly available sample of healthy participants (N=833) scanned on two consecutive days. We also assess the consequences on reliability of three methodological procedures for which a clear guideline in the community is lacking: atlas choice, global signal regression and thresholding. By adopting the intraclass correlation coefficient as a reliability metric, we demonstrate that a relatively small portion of the intrinsic functional connectome is characterized by good (4-6%) to excellent (0.08-1%) stability over time. In particular, connectivity between prefrontal, parietal and temporal areas appears to be especially stable over short timescales. Also, while unreliable edges of the functional connectome are generally weak in terms of average functional connectivity, reliable edges are not necessarily strong. Methodologically, we demonstrate that multimodal parcellation and averaging of connections within known networks are practices that improve reliability. Harnessing this knowledge, for example by honing in on the reliable portion of the connectome, offers one way forward for studies of trait-like features within the normative connectome and for discovery of biomarkers in clinical cohorts.

Author(s):  
Hannah Keppler ◽  
Sofie Degeest ◽  
Bart Vinck

Purpose The objective of the current study was to investigate the short-term test–retest reliability of contralateral suppression (CS) of click-evoked otoacoustic emissions (CEOAEs) using commercially available otoacoustic emission equipment. Method Twenty-three young normal-hearing subjects were tested. An otoscopic evaluation, admittance measures, pure-tone audiometry, measurements of CEOAEs without and with contralateral acoustic stimulation (CAS) to determine CS were performed at baseline ( n = 23), an immediate retest without and with refitting of the probe (only CS of CEOAEs; n = 11), and a retest after 1 week ( n = 23) were performed. Test–retest reliability parameters were determined on CEOAE response amplitudes without and with CAS, and on raw and normalized CS indices between baseline and the other test moments. Results Repeated-measures analysis of variance indicated no random or systematic changes in CEOAE response amplitudes without and with CAS, and in raw and normalized CS indices between the test moments. Moderate-to-high intraclass correlation coefficients with mostly high significant between-subjects variability between baseline and each consecutive test moment were found for CEOAE response amplitude without and with CAS, and for the raw and normalized CS indices. Other reliability parameters deteriorated between CEOAE response amplitudes with CAS as compared to without CAS, between baseline and retest with probe refitting, and after 1 week, as well as for frequency-specific raw and normalized CS indices as compared to global CS indices. Conclusions There was considerable variability in raw and normalized CS indices as measured using CEOAEs with CAS using commercially available otoacoustic emission equipment. More research is needed to optimize the measurement of CS of CEOAEs and to reduce influencing factors, as well as to make generalization of test–retest reliability data possible.


2017 ◽  
Vol 7 (3) ◽  
pp. 208-216 ◽  
Author(s):  
Amanda M. O’Brien ◽  
Joseph E. Casey ◽  
Rachel M. Salmon

2020 ◽  
Vol 4 (3) ◽  
pp. 925-945
Author(s):  
Leonardo Tozzi ◽  
Scott L. Fleming ◽  
Zachary D. Taylor ◽  
Cooper D. Raterink ◽  
Leanne M. Williams

Countless studies have advanced our understanding of the human brain and its organization by using functional magnetic resonance imaging (fMRI) to derive network representations of human brain function. However, we do not know to what extent these “functional connectomes” are reliable over time. In a large public sample of healthy participants ( N = 833) scanned on two consecutive days, we assessed the test-retest reliability of fMRI functional connectivity and the consequences on reliability of three common sources of variation in analysis workflows: atlas choice, global signal regression, and thresholding. By adopting the intraclass correlation coefficient as a metric, we demonstrate that only a small portion of the functional connectome is characterized by good (6–8%) to excellent (0.08–0.14%) reliability. Connectivity between prefrontal, parietal, and temporal areas is especially reliable, but also average connectivity within known networks has good reliability. In general, while unreliable edges are weak, reliable edges are not necessarily strong. Methodologically, reliability of edges varies between atlases, global signal regression decreases reliability for networks and most edges (but increases it for some), and thresholding based on connection strength reduces reliability. Focusing on the reliable portion of the connectome could help quantify brain trait-like features and investigate individual differences using functional neuroimaging.


2006 ◽  
Vol 34 (9) ◽  
pp. 1081-1086 ◽  
Author(s):  
Christopher Alan Lewis ◽  
Sharon Mary Cruise ◽  
Conor Mc Guckin ◽  
Leslie J. Francis

Recently two studies have reported on the test-retest reliability of the Francis Scale of Attitude toward Christianity; however, these studies were limited to samples of university students. This study examined the temporal stability of both the 24- and 7-item versions of the junior version of the Francis Scale of Attitude toward Christianity (Francis, 1978; Francis, Greer, & Gibson, 1991) over a six-week period among a sample of 58 English children aged between 9 and 11 years old. Data demonstrated that stability across the two administrations was very high for both the 24- (r=.74) and 7-item (r=.67) versions, and there was no significant change between Time 1 and Time 2 for either version. These data support the short-term test-retest reliability of both the 24- and 7-item versions of the junior version of the Francis Scale of Attitude toward Christianity among children.


PLoS ONE ◽  
2015 ◽  
Vol 10 (9) ◽  
pp. e0137282 ◽  
Author(s):  
Bertram J. Jobst ◽  
Mark O. Wielpütz ◽  
Simon M. F. Triphan ◽  
Angela Anjorin ◽  
Julia Ley-Zaporozhan ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document