Microfluidic assay for simultaneous culture of multiple cell types on surfaces or within hydrogels
Open accessAbstract
This protocol describes a simple but robust microfluidic assay combining three-dimensional (3D) and two-dimensional (2D) cell culture. The microfluidic platform comprises hydrogel-incorporating chambers between surface-accessible microchannels. By using this platform, well-defined biochemical and biophysical stimuli can be applied to multiple cell types interacting over distances of <1 mm, thereby replicating many aspects of the in vivo microenvironment. Capabilities exist for time-dependent manipulation of flow and concentration gradients as well as high-resolution real-time imaging for observing spatial-temporal single-cell behavior, cell-cell communication, cell-matrix interactions and cell population dynamics. These heterotypic cell type assays can be used to study cell survival, proliferation, migration, morphogenesis and differentiation under controlled conditions. Applications include the study of previously unexplored cellular interactions, and they have already provided new insights into how biochemical and biophysical factors regulate interactions between populations of different cell types. It takes 3 d to fabricate the system and experiments can run for up to several weeks.
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
A separate co-culture system grows each cell type in a separate chamber and achieves cell-cell interaction by substance diffusion through culture media between chambers.
“Instead of simultaneously culturing various cell types in the same chamber, a separate coculture system grows each cell type in a separate chamber and all the cell-cell interaction is achieved by substance diffusion through the culture media between individual culture chambers [131, 139-148] (Figure 4b).”
From Microfluidic modelling of the tumor microenvironment for anti-cancer drug development (2019) · cites this paper as [140]
The Anticipated Results section (page unavailable) describes different cell types cultured in separate channels and paracrine interactions across a hydrogel. But it also reports cells migrating through the gel to interact with other cells, so it does not support the claim that all interaction occurs by diffusion through culture media. (LLM, conf=0.88)
Experimental — accuracy not yet measured
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Cites
The third dimension bridges the gap between cell culture and live tissue
Pampaloni, F., Reynaud, E. G., & Stelzer, E. H. K. (2007) · Nature Reviews Molecular Cell Biology · doi:10.1038/nrm2236 · Cited by 2,817 · see citing works
Soft lithography for micro- and nanoscale patterning
Qin, D., Xia, Y., & Whitesides, G. M. (2010) · Nature Protocols · doi:10.1038/nprot.2009.234 · Cited by 2,339 · see citing works
Capturing complex 3D tissue physiology in vitro
Griffith, L. G., & Swartz, M. A. (2006) · Nature Reviews Molecular Cell Biology · doi:10.1038/nrm1858 · Cited by 2,274 · see citing works
Modeling Tissue Morphogenesis and Cancer in 3D
Yamada, K. M., & Cukierman, E. (2007) · Cell · doi:10.1016/j.cell.2007.08.006 · Cited by 1,751 · see citing works
Cell interactions with three-dimensional matrices
Cukierman, E., Pankov, R. G., & Yamada, K. M. (2002) · Current Opinion in Cell Biology · doi:10.1016/s0955-0674(02)00364-2 · Cited by 889 · see citing works
Cell migration into scaffolds under co-culture conditions in a microfluidic platform
Chung, S. H., Sudo, R., Mack, P. J., Wan, C.-R., Vickerman, V., & Kamm, R. D. (2008) · Lab on a Chip · doi:10.1039/b807585a · Cited by 517 · see citing works
Self-citationMicrofluidic culture platform for neuroscience research
Park, J. W., Vahidi, B., Taylor, A. M., Rhee, S. W., & Jeon, N. L. (2006) · Nature Protocols · doi:10.1038/nprot.2006.316 · Cited by 466 · see citing works
Even‐Ram, S., & Yamada, K. M. (2005) · Current Opinion in Cell Biology · doi:10.1016/j.ceb.2005.08.015 · Cited by 466 · see citing works
Vickerman, V., Blundo, J. T., Chung, S. H., & Kamm, R. D. (2008) · Lab on a Chip · doi:10.1039/b802395f · Cited by 337 · see citing works
Self-citationGhajar, C. M., Blevins, K. S., Hughes, C. C. W., George, S. C., & Putnam, A. J. (2006) · Tissue Engineering · doi:10.1089/ten.2006.12.2875 · Cited by 224 · see citing works
Transport‐mediated angiogenesis in 3D epithelial coculture
Sudo, R., Chung, S. H., Zervantonakis, I. K., Vickerman, V., Toshimitsu, Y., Griffith, L. G., & Kamm, R. D. (2009) · The FASEB Journal · doi:10.1096/fj.08-122820 · Cited by 201 · see citing works
Self-citationIn vitro 3D collective sprouting angiogenesis under orchestrated ANG-1 and VEGF gradients
Shin, Y., Jeon, J. S., Han, S., Jung, G.-S., Shin, S., Lee, S., Sudo, R., Kamm, R. D., & Chung, S. H. (2011) · Lab on a Chip · doi:10.1039/c1lc20039a · Cited by 166 · see citing works
Self-citationWenger, A., Stahl, A., Weber, H., Finkenzeller, G., Augustin, H. G., Stark, G. B., & Kneser, U. (2004) · Tissue Engineering · doi:10.1089/ten.2004.10.1536 · Cited by 165 · see citing works
A high-throughput microfluidic assay to study neurite response to growth factor gradients
Kothapalli, C. R., van Veen, J. E., de Valence, S., Chung, S. H., Zervantonakis, I. K., Gertler, F. B., & Kamm, R. D. (2010) · Lab on a Chip · doi:10.1039/c0lc00240b · Cited by 161 · see citing works
Self-citationMicrofluidic Platforms for Studies of Angiogenesis, Cell Migration, and Cell–Cell Interactions
Chung, S. H., Sudo, R., Vickerman, V., Zervantonakis, I. K., & Kamm, R. D. (2010) · Annals of Biomedical Engineering · doi:10.1007/s10439-010-9899-3 · Cited by 154 · see citing works
Self-citationNew dimensions in tumor immunology: what does 3D culture reveal?
Feder-Mengus, C., Ghosh, S., Reschner, A., Martin, I., & Spagnoli, G. C. (2008) · Trends in Molecular Medicine · doi:10.1016/j.molmed.2008.06.001 · Cited by 139 · see citing works
Zervantonakis, I. K., Kothapalli, C. R., Chung, S. H., Sudo, R., & Kamm, R. D. (2011) · Biomicrofluidics · doi:10.1063/1.3553237 · Cited by 137 · see citing works
Self-citationJeong, G. S., Han, S., Shin, Y., Kwon, G. H., Kamm, R. D., Lee, S., & Chung, S. H. (2011) · Analytical Chemistry · doi:10.1021/ac202170e · Cited by 119 · see citing works
Self-citationHot embossing for fabrication of a microfluidic 3D cell culture platform
Jeon, J. S., Chung, S. H., Kamm, R. D., & Charest, J. L. (2010) · Biomedical Microdevices · doi:10.1007/s10544-010-9496-0 · Cited by 115 · see citing works
Self-citationSurface‐Treatment‐Induced Three‐Dimensional Capillary Morphogenesis in a Microfluidic Platform
Chung, S. H., Sudo, R., Zervantonakis, I. K., Rimchala, T., & Kamm, R. D. (2009) · Advanced Materials · doi:10.1002/adma.200901727 · Cited by 93 · see citing works
Self-citationPaguirigan, A. L., & Beebe, D. J. (2007) · Nature Protocols · doi:10.1038/nprot.2007.256 · Cited by 92 · see citing works
Differentiation of Embryonic Stem Cells into Cardiomyocytes in a Compliant Microfluidic System
Wan, C.-R., Chung, S., & Kamm, R. D. (2011) · Annals of Biomedical Engineering · doi:10.1007/s10439-011-0275-8 · Cited by 87 · see citing works
Self-citationInvestigation of bacterial chemotaxis in flow-based microfluidic devices
Englert, D. L., Manson, M. D., & Jayaraman, A. (2010) · Nature Protocols · doi:10.1038/nprot.2010.18 · Cited by 77 · see citing works
Han, S., Yang, K., Shin, Y., Lee, J. S., Kamm, R. D., Chung, S. H., & Cho, S. (2012) · Lab on a Chip · doi:10.1039/c2lc21285d · Cited by 69 · see citing works
Self-citationJeong, G. S., Kwon, G. H., Kang, A. R., et al. (2011) · Biomedical Microdevices · doi:10.1007/s10544-011-9541-7 · Cited by 50 · see citing works
Biomechanical Regulation of Endothelium-dependent Events Critical for Adaptive Remodeling
Mack, P. J., Zhang, Y., Chung, S., et al. (2008) · Journal of Biological Chemistry · doi:10.1074/jbc.m804524200 · Cited by 49 · see citing works
Self-citationAmadi, O. C., Steinhauser, M. L., Nishi, Y., Chung, S. H., Kamm, R. D., McMahon, A. P., & Lee, R. T. (2010) · Biomedical Microdevices · doi:10.1007/s10544-010-9457-7 · Cited by 41 · see citing works
Self-citationConcentration gradients in microfluidic 3D matrix cell culture systems
Zervantonakis, I. K., Chung, S. H., Sudo, R., Zhang, M., Charest, J. L., & Kamm, R. D. (2010) · International Journal of Micro-Nano Scale Transport · doi:10.1260/1759-3093.1.1.27 · Cited by 36 · see citing works
Self-citation
Flagged first, then by citations
Research works printed but not linked: 1
- [20]Sudo R Transport-mediated angiogenesis in 3D epithelial coculture. The FASEB Journal 2009 23 2155 2164 PMC2718841 19246488
Cited by
Sorted by citations
Advances in organ-on-a-chip engineering
Zhang, B., Korolj, A., Lai, B. F. L., & Radisic, M. (2018) · Nature Reviews Materials · doi:10.1038/s41578-018-0034-7 · Cited by 1,017 · see citing works
Campisi, M., Shin, Y., Osaki, T., Hajal, C., Chiono, V., & Kamm, R. D. (2018) · Biomaterials · doi:10.1016/j.biomaterials.2018.07.014 · Cited by 718 · see citing works
Self-citationHuman 3D vascularized organotypic microfluidic assays to study breast cancer cell extravasation
Jeon, J. S., Bersini, S., Gilardi, M., Dubini, G., Charest, J. L., Moretti, M., & Kamm, R. D. (2015) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1417115112 · Cited by 723 · see citing works
Self-citationMicrofabrication of human organs-on-chips
Huh, D., Kim, H. J., Fraser, J. P., Shea, D. E., Khan, M., Bahinski, A., Hamilton, G. A., & Ingber, D. E. (2013) · Nature Protocols · doi:10.1038/nprot.2013.137 · Cited by 712 · see citing works
Yi, H.-G., Jeong, Y. H., Kim, Y., Choi, Y.-J., Moon, H. E., Park, S. H., Kang, K. S., Bae, M., Jang, J., Youn, H., et al. (2019) · Nature Biomedical Engineering · doi:10.1038/s41551-019-0363-x · Cited by 634 · see citing works
A microfluidic 3D in vitro model for specificity of breast cancer metastasis to bone
Bersini, S., Jeon, J. S., Dubini, G., Arrigoni, C., Chung, S., Charest, J. L., Moretti, M., & Kamm, R. D. (2014) · Biomaterials · doi:10.1016/j.biomaterials.2013.11.050 · Cited by 534 · see citing works
Self-citationChen, M. B., Whisler, J. A., Fröse, J., Yu, C., Shin, Y., & Kamm, R. D. (2017) · Nature Protocols · doi:10.1038/nprot.2017.018 · Cited by 385 · see citing works
Self-citationMechanisms of tumor cell extravasation in an in vitro microvascular network platform
Chen, M. B., Whisler, J. A., Jeon, J. S., & Kamm, R. D. (2013) · Integrative Biology · doi:10.1039/c3ib40149a · Cited by 308 · see citing works
Self-citationRecent advances in microfluidic technologies for cell-to-cell interaction studies
Rothbauer, M., Zirath, H., & Ertl, P. (2018) · Lab on a Chip · doi:10.1039/c7lc00815e · Cited by 277 · see citing works
Mechanotransduction of fluid stresses governs 3D cell migration
Polacheck, W. J., German, A. E., Mammoto, A., Ingber, D. E., & Kamm, R. D. (2014) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1316848111 · Cited by 265 · see citing works
Self-citationChuah, Y. J., Koh, Y. T., Lim, K., Menon, N. V., Wu, Y., & Kang, Y. (2015) · Scientific Reports · doi:10.1038/srep18162 · Cited by 262 · see citing works
In vitro model of tumor cell extravasation
Jeon, J. S., Zervantonakis, I. K., Chung, S., Kamm, R. D., & Charest, J. L. (2013) · PLoS ONE · doi:10.1371/journal.pone.0056910 · Cited by 233 · see citing works
Self-citationMicrofluidic modelling of the tumor microenvironment for anti-cancer drug development
Shang, M., Soon, R. H., Lim, C. T., Khoo, B. L., & Han, J. (2019) · Lab on a Chip · doi:10.1039/c8lc00970h · Cited by 227 · see citing works
Intrinsic Immunogenicity of Small Cell Lung Carcinoma Revealed by Its Cellular Plasticity
Mahadevan, N. R., Knelson, E. H., Wolff, J. O., Vajdi, A., Saigí, M., Campisi, M., Hong, D., Thai, T. C., Piel, B., Han, S., et al. (2021) · Cancer Discovery · doi:10.1158/2159-8290.cd-20-0913 · Cited by 227 · see citing works
Self-citationKim, K.-T., Lee, H. W., Lee, H.-O., Song, H. J., Jeong, D. E., Shin, S., Kim, H., Shin, Y., Nam, D.-H., Jeong, B. C., et al. (2016) · Genome Biology · doi:10.1186/s13059-016-0945-9 · Cited by 198 · see citing works
Self-citationBioprinting towards physiologically relevant tissue models for pharmaceutics
Peng, W., Unutmaz, D., & Ozbolat, I. T. (2016) · Trends in Biotechnology · doi:10.1016/j.tibtech.2016.05.013 · Cited by 196 · see citing works
Nguyen, T. A., Yin, T.-I., Reyes, D., & Urban, G. A. (2013) · Analytical Chemistry · doi:10.1021/ac402761s · Cited by 189 · see citing works
Parlato, S., De Ninno, A., Molfetta, R., Toschi, E., Salerno, D., Mencattini, A., Romagnoli, G., Fragale, A., Roccazzello, L., Buoncervello, M., et al. (2017) · Scientific Reports · doi:10.1038/s41598-017-01013-x · Cited by 181 · see citing works
Cross talk between cancer and immune cells: exploring complex dynamics in a microfluidic environment
Businaro, L., De Ninno, A., Schiavoni, G., Lucarini, V., Ciasca, G., Gerardino, A., Belardelli, F., Gabriele, L., & Mattei, F. (2013) · Lab Chip · doi:10.1039/c2lc40887b · Cited by 162 · see citing works
Unger, C., Kramer, N., Walzl, A., Scherzer, M., Hengstschläger, M., & Dolznig, H. (2014) · Advanced Drug Delivery Reviews · doi:10.1016/j.addr.2014.10.015 · Cited by 158 · see citing works
Buchanan, C. F., Voigt, E. E., Szot, C. S., Freeman, J. W., Vlachos, P. P., & Rylander, M. N. (2014) · Tissue Engineering Part C: Methods · doi:10.1089/ten.tec.2012.0731 · Cited by 143 · see citing works
Gioiella, F., Urciuolo, F., Imparato, G., Brancato, V., & Netti, P. A. (2016) · Advanced Healthcare Materials · doi:10.1002/adhm.201600772 · Cited by 112 · see citing works
Characterizing the role of monocytes in T cell cancer immunotherapy using a 3d microfluidic model
Lee, S. W. L., Adriani, G., Ceccarello, E., Pavesi, A., Tan, A. T., Bertoletti, A., Kamm, R. D., & Wong, S. C. (2018) · Frontiers in Immunology · doi:10.3389/fimmu.2018.00416 · Cited by 109 · see citing works
Self-citationA review of chemical gradient systems for cell analysis
Somaweera, H., Ibraguimov, A., & Pappas, D. (2016) · Analytica Chimica Acta · doi:10.1016/j.aca.2015.12.008 · Cited by 98 · see citing works
Simultaneous or Sequential Orthogonal Gradient Formation in a 3D Cell Culture Microfluidic Platform
Uzel, S. G. M., Amadi, O. C., Pearl, T. M., Lee, R. T., So, P. T. C., & Kamm, R. D. (2016) · Small · doi:10.1002/smll.201501905 · Cited by 100 · see citing works
Self-citationSong, J., Miermont, A., Lim, C. T., & Kamm, R. D. (2018) · Scientific Reports · doi:10.1038/s41598-018-36381-5 · Cited by 87 · see citing works
Self-citationMicrofluidic high-throughput 3D cell culture
Ko, J., Park, D., Lee, J., Jung, S., Baek, K., Sung, K. E., Lee, J., & Jeon, N. L. (2024) · Nature Reviews Bioengineering · doi:10.1038/s44222-024-00163-8 · Cited by 88 · see citing works
In vitro models of the metastatic cascade: from local invasion to extravasation
Bersini, S., Jeon, J. S., Moretti, M., & Kamm, R. D. (2014) · Drug Discovery Today · doi:10.1016/j.drudis.2013.12.006 · Cited by 71 · see citing works
Self-citationBai, J., Tu, T.-Y., Kim, C., Thiery, J. P., & Kamm, R. D. (2015) · Oncotarget · doi:10.18632/oncotarget.5464 · Cited by 70 · see citing works
Self-citationThe CCL2-CCR2 astrocyte-cancer cell axis in tumor extravasation at the brain
Hajal, C., Shin, Y., Li, L., Serrano, J. C., Jacks, T., & Kamm, R. D. (2021) · Science Advances · doi:10.1126/sciadv.abg8139 · Cited by 69 · see citing works
Self-citationBridging the gap: microfluidic devices for short and long distance cell–cell communication
Vu, T. Q., de Castro, R. M. B., & Qin, L. (2017) · Lab on a Chip · doi:10.1039/c6lc01367h · Cited by 63 · see citing works
Ahn, J., Ohk, K., Won, J., Choi, D.-H., Jung, Y. H., Yang, J. H., Jun, Y., Kim, J.-A., Chung, S., & Lee, S.-H. (2023) · Nature Communications · doi:10.1038/s41467-023-37187-4 · Cited by 65 · see citing works
Self-citationLee, S. W. L., Seager, R. J., Litvak, F., Spill, F., Sieow, J. L., Leong, P. H., Kumar, D., Tan, A. S. M., Wong, S. C., Adriani, G., et al. (2020) · Integrative Biology · doi:10.1093/intbio/zyaa007 · Cited by 60 · see citing works
A microfluidic model for organ-specific extravasation of circulating tumor cells
Riahi, R., Yang, Y. L., Kim, H., Jiang, L., Wong, P. K., & Zohar, Y. (2014) · Biomicrofluidics · doi:10.1063/1.4868301 · Cited by 60 · see citing works
A microfluidic co-culture system to monitor tumor-stromal interactions on a chip
Menon, N. V., Chuah, Y. J., Cao, B., Lim, M., & Kang, Y. (2014) · Biomicrofluidics · doi:10.1063/1.4903762 · Cited by 53 · see citing works
Koens, R., Tabata, Y., Serrano, J. C., Aratake, S., Yoshino, D., Kamm, R. D., & Funamoto, K. (2020) · APL Bioengineering · doi:10.1063/1.5127069 · Cited by 53 · see citing works
Self-citationIbrahim, L. I., Hajal, C., Offeddu, G. S., Gillrie, M. R., & Kamm, R. D. (2022) · Biomaterials · doi:10.1016/j.biomaterials.2022.121728 · Cited by 53 · see citing works
Self-citationMultiscale microenvironmental perturbation of pluripotent stem cell fate and self-organization
Tabata, Y., & Lutolf, M. P. (2017) · Scientific Reports · doi:10.1038/srep44711 · Cited by 37 · see citing works
Del Amo, C., Borau, C., Movilla, N., Asín, J., & García-Aznar, J. M. (2017) · Integrative Biology · doi:10.1039/c7ib00022g · Cited by 38 · see citing works
3D fluid-dynamic ovarian cancer model resembling systemic drug administration for efficacy assay
Marrella, A. (2020) · ALTEX · doi:10.14573/altex.2003131 · Cited by 36 · see citing works
A 3D pancreatic tumor model to study T cell infiltration
Mollica, H., Teo, Y. J., Tan, A. S. M., Tan, D. Z. M., Decuzzi, P., Pavesi, A., & Adriani, G. (2021) · Biomaterials Science · doi:10.1039/d1bm00210d · Cited by 32 · see citing works
Qi, H., Huang, G., Han, Y. L., Lin, W., Li, X., Wang, S., Lu, T. J., & Xu, F. (2016) · Critical Reviews in Biotechnology · doi:10.3109/07388551.2014.922917 · Cited by 26 · see citing works
Advances in microfluidic 3D cell culture for preclinical drug development
(2022) · Progress in Molecular Biology and Translational Science · doi:10.1016/bs.pmbts.2021.07.022 · Cited by 23 · see citing works
Huang, Y.-H., Watanabe, M., Yamashita, T., & Sudo, R. (2025) · Biofabrication · doi:10.1088/1758-5090/adc8d4 · Cited by 3 · see citing works
Self-citationA human iPSC-Derived myelination model for investigating fetal brain injuries
Hiraiwa, T., Yoshii, S., Kawada, J., Sugawara, T., Kawasaki, T., Shibata, S., Shindo, T., Fujimori, K., Umezawa, A., & Akutsu, H. (2025) · Regenerative Therapy · doi:10.1016/j.reth.2025.02.014 · Cited by 3 · see citing works
- Authors
- Shin, Y., Han, S., Jeon, J. S., Yamamoto, K., Zervantonakis, I. K., Sudo, R., Kamm, R. D., & Chung, S.
- Affiliations
- Korea University (KR)
- Massachusetts Institute of Technology (US)
- Keio University (JP)
- Corresponding author
- Kamm, Roger D
- Chung, Seok
- ORCID
- Venue
- Nature Protocols
- Published
- 2012-06-07
- Volume
- 7
- Issue
- 7
- Pages
- 1247-1259
- ISSN
- 1750-2799 (ISSN-L)
- 1754-2189
- PMC
- PMC4035049
- OpenAlex
- W1553969354
- Semantic Scholar
- 93843ef05089c6c37b43f852f0b28e75f7d105d1
- Cited by
- 617
- References
- 28
- Citations by year
- 2026: 34 · 2025: 28 · 2024: 26 · 2023: 60 · 2022: 55 · 2021: 62 · 2020: 49 · 2019: 38 · 2018: 53 · 2017: 57 · 2016: 51 · 2015: 35 · 2014: 26 · 2013: 36 · 2012: 7
- FWCI
- 18.88
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Nature Protocols (publishedVersion)
- PubMed (publishedVersion)
- Europe PMC (PubMed Central) (acceptedVersion)
- PubMed Central (acceptedVersion)
- DSpace@MIT (Massachusetts Institute of Technology) (submittedVersion, cc-by-nc-sa)
- PMC
- Funders
- Japan Society for the Promotion of Science (24659591)
- National Cancer Institute (R33CA174550)
- Topics
- Physical Sciences › Engineering › Biomedical Engineering › 3D Printing in Biomedical Research
- Physical Sciences › Engineering › Biomedical Engineering › Microfluidic and Capillary Electrophoresis Applications
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Cellular Mechanics and Interactions
- Keywords
- microfluidics, hydrogels, 3D cell culture, 2D cell culture, intercellular communication, cell-matrix interactions, cell migration, cell differentiation, morphogenesis, cell survival, cell proliferation, single-cell imaging, cell population dynamics
- MeSH terms
- Cell Physiological Phenomena, Dimethylpolysiloxanes, Nylons, Cell Culture Techniques, Hydrogels, Nanotechnology, Microfluidic Analytical Techniques
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
