Merging pathology with biomechanics using CHIMERA (Closed-Head Impact Model of Engineered Rotational Acceleration): a novel, surgery-free model of traumatic brain injury
Open accessAbstract
BACKGROUND: Traumatic brain injury (TBI) is a major health care concern that currently lacks any effective treatment. Despite promising outcomes from many preclinical studies, clinical evaluations have failed to identify effective pharmacological therapies, suggesting that the translational potential of preclinical models may require improvement. Rodents continue to be the most widely used species for preclinical TBI research. As most human TBIs result from impact to an intact skull, closed head injury (CHI) models are highly relevant, however, traditional CHI models suffer from extensive experimental variability that may be due to poor control over biomechanical inputs. Here we describe a novel CHI model called CHIMERA (Closed-Head Impact Model of Engineered Rotational Acceleration) that fully integrates biomechanical, behavioral, and neuropathological analyses. CHIMERA is distinct from existing neurotrauma model systems in that it uses a completely non-surgical procedure to precisely deliver impacts of prescribed dynamic characteristics to a closed skull while enabling kinematic analysis of unconstrained head movement. In this study, we characterized head kinematics as well as functional, neuropathological, and biochemical outcomes up to 14d following repeated TBI (rTBI) in adult C57BL/6 mice using CHIMERA. RESULTS: Head kinematic analysis showed excellent repeatability over two closed head impacts separated at 24h. Injured mice showed significantly prolonged loss of righting reflex and displayed neurological, motor, and cognitive deficits along with anxiety-like behavior. Repeated TBI led to diffuse axonal injury with extensive microgliosis in white matter from 2-14d post-rTBI. Injured mouse brains also showed significantly increased levels of TNF-α and IL-1β and increased endogenous tau phosphorylation. CONCLUSIONS: Repeated TBI using CHIMERA mimics many of the functional and pathological characteristics of human TBI with a reliable biomechanical response of the head. This makes CHIMERA well suited to investigate the pathophysiology of TBI and for drug development programs.
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 righting reflex under 15 min is indicative of a mild injury.
“The longest righting reflex recorded remained under 15 min (900 s), which is indicative of a mild injury [106].”
From Early onset senescence and cognitive impairment in a murine model of repeated mTBI (2021) · cites this paper as [106]
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 Epidemiology and Impact of Traumatic Brain Injury: A Brief Overview
Langlois, J., Rutland-Brown, W., & Wald, M. (2006) · The journal of head trauma rehabilitation · doi:10.1097/00001199-200609000-00001 · Cited by 3,893 · see citing works
National Center for Injury Prevention and Control (U.S.). Division of Injury Response., Faul, M., Wald, M. M., Wu, L., & Coronado, V. G. (2010) · doi:10.15620/cdc.5571 · Cited by 3,494 · see citing works
Mild traumatic brain injury in U.S. soldiers returning from Iraq
Hoge, C. W., McGurk, D., Thomas, J. L., Cox, A. L., Engel, C. C., & Castro, C. A. (2008) · New England Journal of Medicine · doi:10.1056/nejmoa072972 · Cited by 2,775 · see citing works
Ghajar, J. (2000) · The Lancet · doi:10.1016/s0140-6736(00)02689-1 · Cited by 2,244 · see citing works
Tau-mediated neurodegeneration in Alzheimer’s disease and related disorders
Ballatore, C., Lee, V. M.-Y., & Trojanowski, J. Q. (2007) · Nature Reviews Neuroscience · doi:10.1038/nrn2194 · Cited by 2,174 · see citing works
The spectrum of disease in chronic traumatic encephalopathy
McKee, A. C., Stein, T. D., Nowinski, C. J., Stern, R. A., Daneshvar, D. H., Alvarez, V. E., Lee, H.-S., Hall, G., Wojtowicz, S. M., Baugh, C. M., et al. (2013) · Brain · doi:10.1093/brain/aws307 · Cited by 2,098 · see citing works
Pathophysiology of traumatic brain injury
Werner, C., & Engelhard, K. (2007) · British Journal of Anaesthesia · doi:10.1093/bja/aem131 · Cited by 1,712 · see citing works
Cassidy, J. D., Carroll, L., Peloso, P. M. J., Borg, J., von Holst, H., Holm, L. W., Kraus, J. F., & Coronado, V. G. (2004) · Journal of Rehabilitation Medicine · doi:10.1080/16501960410023732 · Cited by 1,612 · see citing works
Changing patterns in the epidemiology of traumatic brain injury
Roozenbeek, B., Maas, A. I. R., & Menon, D. K. (2013) · Nature Reviews Neurology · doi:10.1038/nrneurol.2013.22 · Cited by 1,368 · see citing works
The Neurometabolic Cascade of Concussion.
Giza, C. C., & Hovda, D. A. (2001) · PubMed Central · Cited by 1,342 · see citing works
Axonal pathology in traumatic brain injury
Johnson, V. E., Stewart, W., & Smith, D. H. (2013) · Experimental Neurology · doi:10.1016/j.expneurol.2012.01.013 · Cited by 1,273 · see citing works
A new model of diffuse brain injury in rats
Marmarou, A., Foda, M. A. A.-E., van den Brink, W., Campbell, J., Kita, H., & Demetriadou, K. (1994) · Journal of neurosurgery · doi:10.3171/jns.1994.80.2.0291 · Cited by 1,244 · see citing works
A systematic review of brain injury epidemiology in Europe
Tagliaferri, F., Compagnone, C., Koršič, M., Servadei, F., & Kraus, J. F. (2005) · Acta Neurochirurgica · doi:10.1007/s00701-005-0651-y · Cited by 1,223 · see citing works
Diffuse axonal injury in head injury: definition, diagnosis and grading
Adams, J. H., Doyle, D., Ford, I., Gennarelli, T. A., Graham, D. I., & Mclellan, D. R. (1989) · Histopathology · doi:10.1111/j.1365-2559.1989.tb03040.x · Cited by 1,176 · see citing works
Carroll, L., Cassidy, J. D., Holm, L. W., Kraus, J. F., & Coronado, V. G. (2004) · Journal of Rehabilitation Medicine · doi:10.1080/16501960410023877 · Cited by 1,025 · see citing works
Goldstein, L. E., Fisher, A. M., Tagge, C. A., Zhang, X.-L., Velisek, L., Sullivan, J. A., Upreti, C., Kracht, J. M., Ericsson, M., Wojnarowicz, M. W., et al. (2012) · Science Translational Medicine · doi:10.1126/scitranslmed.3003716 · Cited by 958 · see citing works
Thigmotaxis as an index of anxiety in mice. Influence of dopaminergic transmissions
Simon, P. Y. R., Dupuis, R., & Costentin, J. (1994) · Behavioural Brain Research · doi:10.1016/0166-4328(94)90008-6 · Cited by 767 · see citing works
Incidence of traumatic brain injury in New Zealand: a population-based study
Feigin, V. L., Theadom, A., Barker-Collo, S., Starkey, N. J., McPherson, K., Kahan, M., Dowell, A., Brown, P., Parag, V., Kydd, R., et al. (2013) · The Lancet Neurology · doi:10.1016/s1474-4422(12)70262-4 · Cited by 729 · see citing works
Chronic neuropathologies of single and repetitive TBI: substrates of dementia?
Smith, D. H., Johnson, V. E., & Stewart, W. (2013) · Nature Reviews Neurology · doi:10.1038/nrneurol.2013.29 · Cited by 699 · see citing works
Gavett, B. E., Stern, R. A., & McKee, A. C. (2011) · Clinics in Sports Medicine · doi:10.1016/j.csm.2010.09.007 · Cited by 696 · see citing works
Holbourn, A. (1943) · The Lancet · doi:10.1016/s0140-6736(00)87453-x · Cited by 681 · see citing works
Concussion in Professional Football: Reconstruction of Game Impacts and Injuries
Pellman, E. J., Viano, D. C., TUCKER, A. M., Casson, I. R., & Waeckerle, J. F. (2003) · Neurosurgery · doi:10.1093/neurosurgery/53.3.799 · Cited by 675 · see citing works
A new model of diffuse brain injury in rats. Part II: Morphological characterization.
Foda, M. A. A.-E., & Marmarou, A. (1994) · Journal of Neurosurgery · doi:10.3171/jns.1994.80.2.0301 · Cited by 673 · see citing works
(2003) · PsycEXTRA Dataset · doi:10.1037/e371602004-001 · Cited by 605 · see citing works
Mouse closed head injury model induced by a weight-drop device
Flierl, M. A., Stahel, P. F., Beauchamp, K. M., Morgan, S. J., Smith, W. R., & Shohami, E. (2009) · Nature Protocols · doi:10.1038/nprot.2009.148 · Cited by 547 · see citing works
Quantitating the subtleties of microglial morphology with fractal analysis
Karperien, A., Ahammer, H., & Jelinek, H. F. (2013) · Frontiers in Cellular Neuroscience · doi:10.3389/fncel.2013.00003 · Cited by 517 · see citing works
Increase in IL-6, IL-1 and TNF levels in rat brain following traumatic lesion
Taupin, V., Toulmond, S., Serrano, A., Bénavidès, J., & Zavala, F. (1993) · Journal of Neuroimmunology · doi:10.1016/0165-5728(93)90008-m · Cited by 512 · see citing works
Neurobiological consequences of traumatic brain injury
McAllister, T. W. (2011) · Dialogues in Clinical Neuroscience · doi:10.31887/dcns.2011.13.2/tmcallister · Cited by 472 · see citing works
Blast-Related Traumatic Brain Injury: What Is Known?
Taber, K. H., Warden, D. L., & Hurley, R. A. (2006) · Journal of Neuropsychiatry · doi:10.1176/jnp.2006.18.2.141 · Cited by 435 · see citing works
The clinical spectrum of sport-related traumatic brain injury
Jordan, B. D. (2013) · Nature Reviews Neurology · doi:10.1038/nrneurol.2013.33 · Cited by 347 · see citing works
(1996) · PubMed · Cited by 342 · see citing works
Shohami, E., Gallily, R., Mechoulam, R., Bass, R., & Ben‐Hur, T. (1997) · Journal of Neuroimmunology · doi:10.1016/s0165-5728(96)00181-6 · Cited by 337 · see citing works
Recent advances in neurotrauma
Graham, D. I., McIntosh, T. K., Maxwell, W. L., & Nicoll, J. A. R. (2000) · Journal of Neuropathology & Experimental Neurology · doi:10.1093/jnen/59.8.641 · Cited by 328 · see citing works
A mouse model of human repetitive mild traumatic brain injury
Kane, M. J., Angoa‐Pérez, M., Briggs, D. I., Viano, D. C., Kreipke, C. W., & Kuhn, D. M. (2011) · Journal of Neuroscience Methods · doi:10.1016/j.jneumeth.2011.09.003 · Cited by 322 · see citing works
Shitaka, Y., Tran, H., Bennett, R. E., Sanchez, L., Levy, M. A., Dikranian, K. T., & Brody, D. L. (2011) · Journal of Neuropathology & Experimental Neurology · doi:10.1097/nen.0b013e31821f891f · Cited by 307 · see citing works
Concussion in Professional Football: Location and Direction of Helmet Impacts—Part 2
Pellman, E. J., Viano, D. C., TUCKER, A. M., & Casson, I. R. (2003) · Neurosurgery · doi:10.1227/01.neu.0000093499.20604.21 · Cited by 301 · see citing works
Sensory receptors—design principles revisited
Wicher, D. (2013) · Frontiers in Cellular Neuroscience · doi:10.3389/fncel.2013.00001 · Cited by 295 · see citing works
Mouzon, B., Chaytow, H., Crynen, G. C., Bachmeier, C. J., Stewart, J., MULLAN, M. J., Stewart, W. B., Jr., & Crawford, F. (2012) · Journal of Neurotrauma · doi:10.1089/neu.2012.2498 · Cited by 294 · see citing works
Long-Term Consequences: Effects on Normal Development Profile After Concussion
Daneshvar, D. H., Riley, D., Nowinski, C. J., McKee, A. C., Stern, R. A., & Cantu, R. C. (2011) · Physical Medicine and Rehabilitation Clinics of North America · doi:10.1016/j.pmr.2011.08.009 · Cited by 288 · see citing works
Blast‐related mild traumatic brain injury: mechanisms of injury and impact on clinical care
Elder, G. A., & Cristian, A. (2009) · Mount Sinai Journal of Medicine A Journal of Translational and Personalized Medicine · doi:10.1002/msj.20098 · Cited by 252 · see citing works
Assessment of Postural Stability Following Sport-related Concussion
Guskiewicz, K. M. (2003) · Current Sports Medicine Reports · doi:10.1249/00149619-200302000-00006 · Cited by 243 · see citing works
Concussion in Professional Football: Comparison with Boxing Head Impacts—Part 10
Viano, D. C., Casson, I. R., Pellman, E. J., BIR, C. A., Zhang, L., Sherman, D., & Boitano, M. A. (2005) · Neurosurgery · doi:10.1227/01.neu.0000187541.87937.d9 · Cited by 205 · see citing works
Nonfatal Traumatic Brain Injuries from Sports and Recreation Activities--United States, 2001-2005
Gilchrist, J., Thomas, K. E., Wald, M., & Langlois, J. A. (2007) · PsycEXTRA Dataset · doi:10.1037/e660702007-001 · Cited by 194 · see citing works
Isoelectric focusing technology quantifies protein signaling in 25 cells
O’Neill, R. A., Bhamidipati, A., Bi, X., Deb-Basu, D., Cahill, L., Ferrante, J. A., Gentalen, E., Glazer, M., Gossett, J. J., Hacker, K. J., et al. (2006) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0607973103 · Cited by 194 · see citing works
Engelhardt, G. (1996) · Lara D. Veeken · doi:10.1093/rheumatology/35.suppl_1.4 · Cited by 192 · see citing works
Tsenter, J., Beni‐Adani, L., Assaf, Y., Alexandrovich, A. G., Trembovler, V., & Shohami, E. (2008) · Journal of Neurotrauma · doi:10.1089/neu.2007.0452 · Cited by 161 · see citing works
Mechanisms of Traumatic Brain Injury: Biomechanical, Structural and Cellular Considerations
Davis, A. E. (2000) · Critical Care Nursing Quarterly · doi:10.1097/00002727-200011000-00002 · Cited by 144 · see citing works
Giving voice to a silent epidemic
Rusňák, M. (2013) · Nature Reviews Neurology · doi:10.1038/nrneurol.2013.38 · Cited by 126 · see citing works
Challenges in the Development of Rodent Models of Mild Traumatic Brain Injury
DeWitt, D. S., Perez‐Polo, R. J., Hulsebosch, C. E., Dash, P. K., & Robertson, C. S. (2013) · Journal of Neurotrauma · doi:10.1089/neu.2012.2349 · Cited by 116 · see citing works
The Simple Western™: a gel-free, blot-free, hands-free Western blotting reinvention
Nguyen, U. T. T., Squaglia, N., Boge, A., et al. (2011) · Nature Methods · doi:10.1038/nmeth.f.353 · Cited by 114 · see citing works
Namjoshi, D., Good, C. A., Cheng, W. H., Panenka, W. J., Richards, D., Cripton, P. A., & Wellington, C. L. (2013) · Disease Models & Mechanisms · doi:10.1242/dmm.011320 · Cited by 112 · see citing works
Self-citationMultiple Episodes of Mild Traumatic Brain Injury Result in Impaired Cognitive Performance in Mice
Creeley, C. E., Wozniak, D. F., Bayly, P. V., Olney, J. W., & Lewis, L. M. (2004) · Academic Emergency Medicine · doi:10.1111/j.1553-2712.2004.tb00761.x · Cited by 102 · see citing works
The Contrecoup–Coup Phenomenon: A New Understanding of the Mechanism of Closed Head Injury
Drew, L. B., & Drew, W. E. (2004) · Neurocritical Care · doi:10.1385/ncc:1:3:385 · Cited by 99 · see citing works
CONCUSSION IN PROFESSIONAL FOOTBALL
Viano, D. C., Hamberger, A., Bolouri, H., & Säljö, A. (2009) · Neurosurgery · doi:10.1227/01.neu.0000345863.99099.c7 · Cited by 98 · see citing works
Inflammatory Consequences in a Rodent Model of Mild Traumatic Brain Injury
Perez-Polo, J. R., Rea, H. C., Johnson, K. M., Parsley, M. A., Unabia, G. C., Xu, G., Infante, S. K., DeWitt, D. S., & Hulsebosch, C. E. (2013) · Journal of Neurotrauma · doi:10.1089/neu.2012.2650 · Cited by 96 · see citing works
Lamensdorf, I., Eisenhofer, G., Harvey-White, J. D., Hayakawa, Y., Kirk, K., & Kopin, I. J. (2000) · Journal of Neuroscience Research · doi:10.1002/(sici)1097-4547(20000515)60:4 · Cited by 90 · see citing works
A New Model to Produce Sagittal Plane Rotational Induced Diffuse Axonal Injuries
Davidsson, J., & Risling, M. (2011) · Front. Neur. · doi:10.3389/fneur.2011.00041 · Cited by 78 · see citing works
Gutierrez, E., Huang, Y.-L., Haglid, K. G., Bao, F., Hansson, H., Hamberger, A., & Viano, D. C. (2001) · Journal of Neurotrauma · doi:10.1089/08977150151070874 · Cited by 75 · see citing works
The Acute Symptoms of Sport-Related Concussion: Diagnosis and On-field Management
Putukian, M. (2010) · Clinics in Sports Medicine · doi:10.1016/j.csm.2010.09.005 · Cited by 71 · see citing works
New Rat Model for Diffuse Brain Injury Using Coronal Plane Angular Acceleration
Fijalkowski, R. J., Stemper, B., Pintar, F., Yoganandan, N., Crowe, M., & Gennarelli, T. (2007) · Journal of Neurotrauma · doi:10.1089/neu.2007.0268 · Cited by 67 · see citing works
Diffuse axonal injury due to lateral head rotation in a rat model.
He, X.-S., Yi, S., Zhang, X., Zhou, F., Zhang, J.-N., & Li-Sun, Y. (2000) · Journal of Neurosurgery · doi:10.3171/jns.2000.93.4.0626 · Cited by 65 · see citing works
Li, Y., Zhang, L., Kallakuri, S., Zhou, R., & Cavanaugh, J. M. (2011) · Journal of Neurotrauma · doi:10.1089/neu.2010.1687 · Cited by 60 · see citing works
Namjoshi, D., Martin, G., Donkin, J. J., Wilkinson, A., Stukas, S. K., Fan, J., Carr, M., Tabarestani, S., Wuerth, K. C., Hancock, R. E. W., et al. (2013) · PLoS ONE · doi:10.1371/journal.pone.0053529 · Cited by 51 · see citing works
Self-citationWang, H.-C., Duan, Z.-X., Wu, F.-F., Xie, L., Zhang, H., & Ma, Y.-B. (2010) · Journal of Neurotrauma · doi:10.1089/neu.2009.1071 · Cited by 40 · see citing works
Diffuse axonal injury induced by simultaneous moderate linear and angular head accelerations in rats
Li, X. Y., Li, J., Feng, D., & Gu, L. (2010) · Neuroscience · doi:10.1016/j.neuroscience.2010.04.075 · Cited by 32 · see citing works
Development of head injury risk functions based on real-world accident reconstruction
Peng, Y. L., Yang, J., Deck, C., et al. (2013) · International Journal of Crashworthiness · doi:10.1080/13588265.2013.805290 · Cited by 29 · see citing works
Spatiotemporal Pattern of Neuroinflammation After Impact-Acceleration Closed Head Injury in the Rat
Rooker, S., Jander, S., Reempts, J. V. V., Stoll, G., Jorens, P., Borgers, M., & Verlooy, J. (2006) · Mediators of Inflammation · doi:10.1155/mi/2006/90123 · Cited by 27 · see citing works
Subacute Concussion-Related Symptoms in Youth
Blume, H. K., Lucas, S. M., & Bell, K. R. (2011) · Physical Medicine and Rehabilitation Clinics of North America · doi:10.1016/j.pmr.2011.08.007 · Cited by 26 · see citing works
Shein, N. A., Doron, H., Horowitz, M., Trembovler, V., Alexandrovich, A. G., & Shohami, E. (2007) · Brain Research · doi:10.1016/j.brainres.2007.09.024 · Cited by 23 · see citing works
Sevagan, G., Zhu, F., Jiang, B., et al. (2013) · Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine · doi:10.1177/0954411913483430 · Cited by 11 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Chen, H.-X., Liang, F.-C., Gu, P., Xu, B.-L., Xu, H.-J., Wang, W.-T., Hou, J.-Y., Xie, D.-X., Chai, X.-Q., & An, S.-J. (2020) · Cell Death & Disease · doi:10.1038/s41419-020-2473-5 · Cited by 319 · see citing works
White, E. R., Pinar, C., Bostrom, C. A., Meconi, A., & Christie, B. R. (2017) · Journal of Neurotrauma · doi:10.1089/neu.2016.4638 · Cited by 49 · see citing works
Early onset senescence and cognitive impairment in a murine model of repeated mTBI
Schwab, N., Ju, Y., & Hazrati, L.-N. (2021) · Acta Neuropathologica Communications · doi:10.1186/s40478-021-01190-x · Cited by 39 · see citing works
Bachstetter, A. D., Morganti, J. M., Bodnar, C. N., Webster, S. J., Higgins, E. K., Roberts, K. N., Snider, H., Meier, S. E., Nation, G. K., Goulding, D. S., et al. (2020) · Experimental Neurology · doi:10.1016/j.expneurol.2020.113180 · Cited by 29 · see citing works
- Authors
- Namjoshi, D. R., Cheng, W. H., McInnes, K. A., Martens, K. M., Carr, M., Wilkinson, A., Fan, J., Robert, J., Hayat, A., Cripton, P. A., & Wellington, C. L.
- Affiliations
- University of British Columbia (CA)
- Corresponding author
- Wellington, Cheryl L
- ORCID
- Venue
- Molecular Neurodegeneration
- Published
- 2014-12
- Volume
- 9
- Issue
- 1
- Pages
- 55-55
- ISSN
- 1750-1326 (ISSN-L)
- PMC
- PMC4269957
- OpenAlex
- W2142086230
- Cited by
- 195
- References
- 71
- Citations by year
- 2026: 14 · 2025: 20 · 2024: 21 · 2023: 20 · 2022: 12 · 2021: 24 · 2020: 21 · 2019: 22 · 2018: 15 · 2017: 17 · 2016: 7 · 2015: 2
- FWCI
- 5.65
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- cc-by
- Locations
- Molecular Neurodegeneration (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- cIRcle (University of British Columbia) (submittedVersion, cc-by)
- Open Collections
- Funders
- Alzheimer Society
- Alzheimer Society Research Program
- Canadian Institutes of Health Research (123461_1, 123461)
- Topics
- Health Sciences › Medicine › Neurology › Traumatic Brain Injury and Neurovascular Disturbances
- Health Sciences › Medicine › Epidemiology › Traumatic Brain Injury Research
- Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Automotive and Human Injury Biomechanics
- Keywords
- traumatic brain injury, chimeras, angular acceleration, head kinematics, diffuse axonal injury, microglial activation, tau phosphorylation, TNF-α, IL-1β, anxiety-like behavior, cognitive impairment, C57BL/6 mice
- MeSH terms
- Animals, Biomechanical Phenomena, Brain Injuries, Disease Models, Animal, Humans, Male, Mice, Inbred C57BL, Models, Biological, Tumor Necrosis Factor-alpha, Interleukin-1beta
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
