TY - INPR N1 - © 2024 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. KW - T1 mapping KW - inversion recovery KW - open data KW - quantitative MRI KW - reproducibility PB - Wiley A1 - Boudreau, Mathieu A1 - Karakuzu, Agah A1 - Cohen-Adad, Julien A1 - Bozkurt, Ecem A1 - Carr, Madeline A1 - Castellaro, Marco A1 - Concha, Luis A1 - Doneva, Mariya A1 - Dual, Seraina A A1 - Ensworth, Alex A1 - Foias, Alexandru A1 - Fortier, Véronique A1 - Gabr, Refaat E A1 - Gilbert, Guillaume A1 - Glide-Hurst, Carri K A1 - Grech-Sollars, Matthew A1 - Hu, Siyuan A1 - Jalnefjord, Oscar A1 - Jovicich, Jorge A1 - Keskin, Kübra A1 - Koken, Peter A1 - Kolokotronis, Anastasia A1 - Kukran, Simran A1 - Lee, Nam G A1 - Levesque, Ives R A1 - Li, Bochao A1 - Ma, Dan A1 - Mädler, Burkhard A1 - Maforo, Nyasha G A1 - Near, Jamie A1 - Pasaye, Erick A1 - Ramirez-Manzanares, Alonso A1 - Statton, Ben A1 - Stehning, Christian A1 - Tambalo, Stefano A1 - Tian, Ye A1 - Wang, Chenyang A1 - Weiss, Kilian A1 - Zakariaei, Niloufar A1 - Zhang, Shuo A1 - Zhao, Ziwei A1 - Stikov, Nikola A1 - ISMRM Reproducible Research Study Group and the ISMRM Quantitati JF - Magnetic Resonance in Medicine AV - public TI - Repeat it without me: Crowdsourcing the T1 mapping common ground via the ISMRM reproducibility challenge Y1 - 2024/05/10/ SN - 0740-3194 UR - http://dx.doi.org/10.1002/mrm.30111 ID - discovery10192414 N2 - PURPOSE: T1 mapping is a widely used quantitative MRI technique, but its tissue-specific values remain inconsistent across protocols, sites, and vendors. The ISMRM Reproducible Research and Quantitative MR study groups jointly launched a challenge to assess the reproducibility of a well-established inversion-recovery T1 mapping technique, using acquisition details from a seminal T1 mapping paper on a standardized phantom and in human brains. METHODS: The challenge used the acquisition protocol from Barral et al. (2010). Researchers collected T1 mapping data on the ISMRM/NIST phantom and/or in human brains. Data submission, pipeline development, and analysis were conducted using open-source platforms. Intersubmission and intrasubmission comparisons were performed. RESULTS: Eighteen submissions (39 phantom and 56 human datasets) on scanners by three MRI vendors were collected at 3?T (except one, at 0.35?T). The mean coefficient of variation was 6.1% for intersubmission phantom measurements, and 2.9% for intrasubmission measurements. For humans, the intersubmission/intrasubmission coefficient of variation was 5.9/3.2% in the genu and 16/6.9% in the cortex. An interactive dashboard for data visualization was also developed: https://rrsg2020.dashboards.neurolibre.org. CONCLUSION: The T1 intersubmission variability was twice as high as the intrasubmission variability in both phantoms and human brains, indicating that the acquisition details in the original paper were insufficient to reproduce a quantitative MRI protocol. This study reports the inherent uncertainty in T1 measures across independent research groups, bringing us one step closer to a practical clinical baseline of T1 variations in vivo. ER -