The fNIRS Reproducibility Study Hub (FRESH): Exploring Variability and Enhancing Transparency in fNIRS Neuroimaging Research
Authors: Yücel Meryem Ayşe , Luke Robert , Mesquita Rickson Coelho , von Lühmann Alexander , Mehler David Marc Anton , Lührs Michael , Gemignani Jessica , Abdalmalak Androu , Albrecht Franziska , Almeida Iara , Artemenko Christina , Ashton Kira , Augustynowicz Paweł , Bajracharya Aahana , Bannier Elise , Barth Beatrix , Bayet Laurie , Behrendt Jacqueline , Khani Hadi Borj , Borot Lenaic , Borrell Jordan , Brigadoi Sabrina , Brink Kolby , Bulgarelli Chiara , Caruyer Emmanuel , Chen Hsin-Chin , Copeland Chris , Corouge Isabelle , Cutini Simone , Di Lorenzo Renata , Dresler Thomas , Eggebrecht Adam , Ehl Ann-Christine , Erdoğan Sinem , Evenblij Daniëlle , Ferdous Talukdar Raian , Fracalossi Victoria , Franzén Erika , Gallagher Anne , Gerloff Christian , Gervain Judit , Goldhamer Noy , Gossé Louisa K , Guérin Ségolène M. R. , Guevara Edgar , Hosseini Hadi , Innes-Brown Hamish , Int-Veen Isabell , Jaffe-Dax Sagi , Jégou Nolwenn , Kawaguchi Hiroshi , Kelsey Caroline , Kent Michaela , Kessler Roman , Kherbawy Nadeen , Klein Franziska , Kochavi Nofar , Kolisnyk Matthew , Koren Yogev , Kroczek Agnes , Kvist Alexander , Lin Chen , Löw Andreas , Luan Siying , Mao Darren , Martins Gaby G , Middell Eike , Montero-Hernandez Samuel Antonio , Mutlu Murat Can , Novi Sergio , Paquette Natacha , Paranawithana Ishara , Parmet Yisrael , Peelle Jonathan , Peng Ke , Peng Tommy , Pereira João , Pinti Paola , Pollonini Luca , Jounghani Ali Rahimpour , Reindl Vanessa , Zweerings Jana , Schopp Betti , Schulte Alina , Schulte-Rüther Martin , Segel Ari , Seifi-Ala Tirdad , Shader Maureen , Shavit Hadas , Sherafati Arefeh , Soltanlou Mojtaba , Sorger Bettina , Speh Emma , Stubbs Kevin , Stute Katharina , Sullivan Eileen , Tak Sungho , Tipado Zeus , Tremblay Julie , Vahidi Homa , Van Eeckhoutte Maaike , Vannasing Phetsamone , Vergotte Gregoire , Vincent Marion , Weiss Eileen , Yang Dalin , Yükselen Gülnaz , Zapała Dariusz , Zemanek Vit 
Published: September 2024

In neuroimaging research, efforts to enhance replication and reproducibility have increased the focus on improving transparency, particularly in the complex data analysis processes. We conducted a multi-lab collaborative study involving 38 international teams that analyzed two functional Near-Infrared Spectroscopy (fNIRS) datasets. These teams tested seven group-level and forty individual-level hypotheses, and they submitted detailed reports on their analysis pipelines and testing outcomes. The results showed significant variability in hypothesis testing outcomes due to differences in analytical approaches. There was greater consensus in group-level analyses compared to individual-level analyses. Factors such as the pruning method, hemodynamic response function model and estimation, and statistical analysis space partly account for the variability in hypothesis testing outcomes. Additionally, we have found higher similarity in hypothesis testing outcomes across the researchers who reported higher confidence in their analysis skills. This study underscores the importance of complying with best practices in fNIRS analysis methodologies and the need for standardized analysis protocols to improve reliability and credibility.