Enhancing Robustness in Network Neuroscience through Multiverse Analysis - The Comet Toolbox

Poster No:

1442 

Submission Type:

Abstract Submission 

Authors:

Micha Burkhardt1, Carsten Giessing1

Institutions:

1Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany

First Author:

Micha Burkhardt  
Carl von Ossietzky Universität Oldenburg
Oldenburg, Germany

Co-Author:

Carsten Giessing  
Carl von Ossietzky Universität Oldenburg
Oldenburg, Germany

Introduction:

Dynamic functional connectivity (dFC) offers a window into the temporal fluctuations of brain networks, promising novel insights into the dynamic architecture of the brain (Preti et al., 2016). However, reproducibility and robustness remain significant challenges, driven by the complexity of neuroimaging data and the multitude of methodological choices involved in dFC analysis. Various methods for estimating dFC from fMRI data and subsequent graph-theoretical analyses have emerged, but the absence of ground truths often forces researchers to make arbitrary (yet defensible) decisions. These choices can result in considerable variability, raising concerns about the generalizability of findings.

To address these challenges, the concept of multiverse analysis has been proposed as a systematic approach to improve robustness and transparency in data analysis (Steegen et al., 2016). Rather than focusing on a single analysis pipeline, multiverse analysis evaluates all defensible combinations of analytical decisions, revealing how these choices influence outcomes. By aggregating results across pipelines, multiverse analysis provides a clear overview of which effects are robust and which are sensitive to methodological choices, addressing key concerns in reproducibility.

We present Comet, an open-source Python toolbox that unifies dFC estimation, graph-theoretical methods, and multiverse analysis workflows. Comet facilitates the systematic exploration of methodological choices, providing researchers with a meta-scientific approach to assess their impact on research outcomes. By introducing a robust and transparent framework, the Comet Toolbox contributes to enhancing robustness and reproducibility in network neuroscience.

Methods:

Currently, the toolbox includes more than 20 static, dynamic, state-based, and edge-centric connectivity measures. These methods were identified through a systematic literature review to ensure broad coverage of existing approaches. Additionally, optimized graph-theoretical algorithms and full integration of the Brain Connectivity Toolbox (Rubinov and Sporns, 2010) are included, enabling comprehensive network analyses.

The connectivity and graph-theoretical measures are integrated into a flexible multiverse analysis workflow. This workflow allows users to specify decision points within their analysis pipelines and systematically evaluate all valid combinations of decisions. Comet's multiverse analysis features also support complex pipeline structures, including the reordering of analytical steps and exclusion of invalid combinations.

Designed with accessibility and maintainability in mind, the Comet Toolbox features both an intuitive graphical user interface (GUI) and comprehensive scripting capabilities. This ensures suitability for users with diverse technical backgrounds. All functionalities can also be used independently outside of the multiverse analysis workflow, providing flexibility for standalone applications. Extensive documentation and demo scripts are available to facilitate integration into existing workflows (https://comet-toolbox.readthedocs.io/).

Results:

Figure 1 highlights the graphical user interface and the performance improvements for a computationally expensive graph measure (nodal efficiency). Figure 2 presents a specification curve as an example output for a multiverse analysis. It illustrates the variability in results across different analysis pipelines for predicting connectivity states from synthetic fMRI data.
Supporting Image: fig1.png
Supporting Image: fig2.png
 

Conclusions:

Integrating a wide array of dFC methods, graph-based tools, and multiverse analysis workflows, the Comet Toolbox empowers researchers to systematically explore the impact of analytical decisions. Future developments will further expand its functionality, ensuring Comet remains a dynamic and evolving tool for advancing robust and reproducible analyses in network neuroscience. The toolbox is openly available at https://github.com/mibur1/comet.

Modeling and Analysis Methods:

Connectivity (eg. functional, effective, structural) 2
fMRI Connectivity and Network Modeling 1

Neuroinformatics and Data Sharing:

Workflows

Keywords:

Other - functional MRI; fMRI; functional connectivity; dynamic functional connectivity; graph analysis; network neuroscience; multiverse analysis; robustness; reproducibility

1|2Indicates the priority used for review

Abstract Information

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Please indicate which methods were used in your research:

Functional MRI

Provide references using APA citation style.

Preti, M. G. (2016). The dynamic functional connectome: State-of-the-art and perspectives. NeuroImage, 160, 41–54.
Rubinov, M. (2009). Complex network measures of brain connectivity: Uses and interpretations. NeuroImage, 52(3), 1059–1069.
Steegen, S. (2016). Increasing transparency through a multiverse analysis. Perspectives on Psychological Science, 11(5), 702–712.

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