Using preregistration as a tool for transparent fNIRS study design

Abstract

Significance: The expansion of fNIRS methodology and analysis tools give rise to various design and analytical decisions 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 would be 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 about the design and analysis steps involved in fNIRS studies and 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 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 continuous-wave, 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.

Cognitive training based on functional near-infrared spectroscopy neurofeedback for the elderly with mild cognitive impairment: a preliminary study

“…To address the stated limitations and effectively structure fNIRS studies, endorse the use of preregistration, as recently detailed by Schroeder et al (2023). This guide, tailored to fNIRS research, offers key design principles and comprehensive study planning recommendations.…”

Interdisciplinary views of fNIRS: Current advancements, equity challenges, and an agenda for future needs of a diverse fNIRS research community

“…We hope to see advances in this and a stronger culture of open sharing of fNIRS data, as is becoming standard (and often a requirement) for fMRI data, on platforms such as Open Neuro which currently hosts 550 fMRI datasets. Salient efforts to unite the community are underway with the formation of the Society of fNIRS (Yücel et al, 2017), and recent publications encouraging the standardization of fNIRS practices and the further unification of fNIRS researchers (Pinti et al, 2019;Yücel et al, 2021;Schroeder et al, 2022). These efforts may collectively raise awareness and develop tools concerning the issues of personal, societal, and methodological biases that impact fNIRS research.…”

Shedding light on functional near-infrared spectroscopy and open science practices

“…Templates for fMRI and EEG have already been developed, and there have been recent efforts to develop an fNIRS preregistration template. 11 – 13 The fNIRS-specific preregistration could have a structured form field that asks about specific fNIRS protocols (see Table 1 for examples). The template could help to inform researchers of the information that they need to include and provide standardization across labs.…”