Using preregistration as a tool for transparent fNIRS study design

Abstract

Significance: The expansion of functional near-infrared spectroscopy (fNIRS) methodology and analysis tools gives rise to various design and analytical decisions that researchers have to make. Several recent efforts have developed guidelines for preprocessing, analyzing, and reporting practices. For the planning stage of fNIRS studies, similar guidance is desirable. Study preregistration helps researchers to transparently document study protocols before conducting the study, including materials, methods, and analyses, and thus, others to verify, understand, and reproduce a study. Preregistration can thus serve as a useful tool for transparent, careful, and comprehensive fNIRS study design.Aim: We aim to create a guide on the design and analysis steps involved in fNIRS studies and to provide a preregistration template specified for fNIRS studies.Approach: The presented preregistration guide has a strong focus on fNIRS specific requirements, and the associated template provides examples based on continuous-wave (CW) fNIRS studies conducted in humans. These can, however, be extended to other types of fNIRS studies.Results: On a step-by-step basis, we walk the fNIRS user through key methodological and analysis-related aspects central to a comprehensive fNIRS study design. These include items specific to the design of CW, task-based fNIRS studies, but also sections that are of general importance, including an in-depth elaboration on sample size planning.Conclusions: Our guide introduces these open science tools to the fNIRS community, providing researchers with an overview of key design aspects and specification recommendations for comprehensive study planning. As such it can be used as a template to preregister fNIRS studies or merely as a tool for transparent fNIRS study design.

Validating the reproducibility of a low-cost single-channel fNIRS device across hierarchical cognitive tasks

“…Acknowledging the intricacies presented by this pilot study, we advocate for the adoption of preregistration in subsequent research endeavors. This approach, as championed by Schroeder et al (2023) , will enhance the clarity and reproducibility of our scientific inquiry, allowing the researcher to systematically address biases and substantiate the reliability of our results.…”

Effects of Home-Based EEG Neurofeedback Training as a Non-Pharmacological Intervention for Parkinson’s Disease

“…We encourage future efforts to use the CRED-nf checklist 26 to ensure best practice guidelines are followed and rigorous experimental designs continue to be adopted. We also encourage researchers to continue to pre-register their trials and we hope that the documentation of this experiment will inform more detailed pre-registered study protocols in the future 41,42,43 . Lastly, while the present study focused on motor rehabilitation in PD, the shown proof-of-concept for a multi-session supervised neurofeedback experiment in a home-setting may encourage exploration of other clinical use cases.…”

Successful Modulation of Temporoparietal Junction Activity and Stimulus-Driven Attention by fNIRS-based Neurofeedback – a Randomized Controlled Proof-of-Concept Study

“…However, we took care to keep the contribution of systemic physiological changes in our design to a minimum and assessed the robustness of the online analysis through an additional offline analysis using more stringent preprocessing methods. More state-of-the art online artifact control measures and signal processing methods (Klein and Kranczioch, 2019; Lühmann et al, 2020; Klein et al, 2022; Schroeder et al, 2023) are now available and can be used in future studies to sufficiently rule out the contributions of systemic physiology.…”