Fecal microbiota transplantation in clinical practice: Present controversies and future prospects
Open accessAbstract
The gut microbiota, serving as the only "organ" that humans can share, has been extensively applied in the treatment of various intestinal and extraintestinal diseases through fecal microbiota transplantation (FMT) technology. By optimizing the donor selection strategy, FMT exhibited the highest effectiveness (more than 90%) in treating acute intestinal inflammations, such as recurrent Clostridium difficile infection. However, the efficacy diminishes when addressing intestinal functional diseases (more than 60%), chronic intestinal inflammations or organic diseases (less than 60%), and extraintestinal diseases, particularly those lacking any gastrointestinal symptoms (less than 50%). Ongoing efforts to enhance the therapeutic response of FMT across diverse diseases represent a central focus of current clinical research. This review concentrates on donor selection, recipient management, precise donor-recipient matching, antagonistic mechanism of native bacteria to transplanted bacteria, and targeted treatment strategies for different diseases, with the aim of providing practical strategies to improve the clinical efficacy of FMT.
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?
Together with the rapidly growing utility of FMT for treating several other conditions in recent years, FMT offers the greatest immediate hope for producing clinically meaningful therapeutic modulation of the gut microbiome in prodromal and early PD.
“Together with the rapidly growing utility of FMT for treating several other conditions in recent years [210, 211], FMT offers the greatest immediate hope for producing clinically meaningful therapeutic modulation of the gut microbiome in prodromal and early PD.”
From The gut–brain axis in early Parkinson’s disease: from prodrome to prevention (2025) · cites this paper as [210]
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
Gut microbiome influences efficacy of PD-1-based immunotherapy against epithelial tumors
Routy, B., Le Chatelier, E., Derosa, L., Duong, C. P. M., Alou, M. T., Daillère, R., Fluckiger, A., Messaoudene, M., Rauber, C., Roberti, M. P., et al. (2018) · Science · doi:10.1126/science.aan3706 · Cited by 5,671 · see citing works
Gut microbiome modulates response to anti-PD-1 immunotherapy in melanoma patients
Gopalakrishnan, V., Spencer, C. N., Nezi, L., Reuben, A., Andrews, M. C., Karpinets, T. V., Prieto, P. A., Vicente, D., Hoffman, K., Wei, S. C., et al. (2018) · Science · doi:10.1126/science.aan4236 · Cited by 4,812 · see citing works
The Human Intestinal Microbiome in Health and Disease
Lynch, S. V., & Pedersen, O. (2016) · New England Journal of Medicine · doi:10.1056/nejmra1600266 · Cited by 3,637 · see citing works
Dietary-fat-induced taurocholic acid promotes pathobiont expansion and colitis in Il10-/- mice
Devkota, S., Wang, Y., Musch, M. W., Leone, V., Fehlner-Peach, H., Nadimpalli, A., Antonopoulos, D. A., Jabri, B., & Chang, E. B. (2012) · Nature · doi:10.1038/nature11225 · Cited by 1,904 · see citing works
Paramsothy, S., Kamm, M. A., Kaakoush, N. O., Walsh, A. J., van den Bogaerde, J., Samuel, D., Leong, R. W. L., Connor, S., Ng, W., Paramsothy, R., et al. (2017) · The Lancet · doi:10.1016/s0140-6736(17)30182-4 · Cited by 1,276 · see citing works
European consensus conference on faecal microbiota transplantation in clinical practice
Cammarota, G., Ianiro, G., Tilg, H., Rajilić-Stojanović, M., Kump, P., Satokari, R., Sokol, H., Arkkila, P., Pintus, C., Hart, A., et al. (2017) · Gut · doi:10.1136/gutjnl-2016-313017 · Cited by 1,207 · see citing works
Human Gut Microbiota from Autism Spectrum Disorder Promote Behavioral Symptoms in Mice
Sharon, G., Cruz, N. J., Kang, D.-W., Gandal, M. J., Wang, B., Kim, Y.-M., Zink, E. M., Casey, C. P., Taylor, B. C., Lane, C. J., et al. (2019) · Cell · doi:10.1016/j.cell.2019.05.004 · Cited by 1,182 · see citing works
Yassour, M., Vatanen, T., Siljander, H., Hämäläinen, A.-M., Härkönen, T., Ryhänen, S. J., Franzosa, E. A., Vlamakis, H., Huttenhower, C., Gevers, D., et al. (2016) · Science Translational Medicine · doi:10.1126/scitranslmed.aad0917 · Cited by 1,043 · see citing works
Gut Microbiota and Colonization Resistance against Bacterial Enteric Infection
Ducarmon, Q. R., Zwittink, R. D., Hornung, B. V. H., van Schaik, W., Young, V. B., & Kuijper, E. J. (2019) · Microbiology and Molecular Biology Reviews · doi:10.1128/mmbr.00007-19 · Cited by 566 · see citing works
Cammarota, G., Ianiro, G., Kelly, C. R., Mullish, B. H., Allegretti, J. R., Kassam, Z., Putignani, L., Fischer, M., Keller, J. J., Costello, S. P., et al. (2019) · Gut · doi:10.1136/gutjnl-2019-319548 · Cited by 506 · cited 1× · see citing works
“The second stage builds upon this by incorporating life history screening [12].”
Ianiro, G., Punčochář, M., Karcher, N., Porcari, S., Armanini, F., Asnicar, F., Beghini, F., Blanco-Míguez, A., Cumbo, F., Manghi, P., et al. (2022) · Nature Medicine · doi:10.1038/s41591-022-01964-3 · Cited by 366 · see citing works
Food, immunity, and the microbiome
Tilg, H., & Moschen, A. R. (2015) · Gastroenterology · doi:10.1053/j.gastro.2014.12.036 · Cited by 292 · see citing works
Haifer, C., Paramsothy, S., Kaakoush, N. O., Saikal, A., Ghaly, S., Yang, T., Luu, L. D. W., Borody, T. J., & Leong, R. W. (2022) · The Lancet Gastroenterology & Hepatology · doi:10.1016/s2468-1253(21)00400-3 · Cited by 285 · see citing works
Drivers and determinants of strain dynamics following fecal microbiota transplantation
Schmidt, T. S. B., Li, S. S., Maistrenko, O. M., Akanni, W., Coelho, L. P., Dolai, S., Fullam, A., Glazek, A. M., Hercog, R., Herrema, H., et al. (2022) · Nature Medicine · doi:10.1038/s41591-022-01913-0 · Cited by 233 · see citing works
Kedia, S., Virmani, S., K Vuyyuru, S., Kumar, P., Kante, B., Sahu, P., Kaushal, K., Farooqui, M., Singh, M., Verma, M., et al. (2022) · Gut · doi:10.1136/gutjnl-2022-327811 · Cited by 201 · see citing works
Sarbagili Shabat, C., Scaldaferri, F., Zittan, E., Hirsch, A., Mentella, M. C., Musca, T., Cohen, N. A., Ron, Y., Fliss Isakov, N., Pfeffer, J., et al. (2022) · Journal of Crohn s and Colitis · doi:10.1093/ecco-jcc/jjab165 · Cited by 110 · see citing works
Kao, D., Wong, K., Franz, R., Cochrane, K., Sherriff, K., Chui, L., Lloyd, C., Roach, B., Bai, A. D., Petrof, E. O., et al. (2021) · The Lancet Gastroenterology & Hepatology · doi:10.1016/s2468-1253(21)00007-8 · Cited by 81 · see citing works
Flagged first, then by citations
Research works printed but not linked: 59
- [1]Wang Y Huang Y Chase RC Li T Ramai D Li S Global burden of digestive diseases: A systematic analysis of the global burden of diseases study, 1990 to 2019 Gastroenterology 165 2023 773 783.e15 37302558
- [2]Tian H. Zhang S. Qin H. Li N. Chen Q. Long-term safety of faecal microbiota transplantation for gastrointestinal diseases in China Lancet Gastroenterol Hepatol 7 2022 702 703 35709800
- [3]Wang Y. Zhang S. Borody T.J. Zhang F. Encyclopedia of fecal microbiota transplantation: A review of effectiveness in the treatment of 85 diseases Chin Med J 135 2022 1927 1939 PMC9746749 36103991
- [4]Fan Y. Pedersen O. Gut microbiota in human metabolic health and disease Nat Rev Microbiol 19 2021 55 71 32887946
- [5]Stripling J Rodriguez M. Current evidence in delivery and therapeutic uses of fecal microbiota transplantation in human diseases-Clostridium difficile disease and beyond Am J Med Sci 356 2018 424 432 30384951
- [7]Li YT Cai HF Wang ZH Xu J Fang JY. Systematic review with meta-analysis: Long-term outcomes of faecal microbiota transplantation for Clostridium difficile infection Aliment Pharmacol Ther 43 2016 445 457 26662643
- [8]Tian H Cui J Ye C Zhao J Yang B Xu Y Depletion of butyrate-producing microbes of the Firmicutes predicts nonresponse to FMT therapy in patients with recurrent Clostridium difficile infection Gut Microb 15 2023 2236362 PMC10361143 37469017
- [10]Zhao D. Ye C. Zhang S. Lv X. Yang B. Analysis of risk factors for early clinical recurrence of inflammatory bowel disease after fecal microbiota transplantation Am J Transl Res 13 2021 12875 12886 PMC8661179 34956503
- [13]Haifer C. Kelly C.R. Paramsothy S. Andresen D. Papanicolas L.E. McKew G.L. Australian consensus statements for the regulation, production and use of faecal microbiota transplantation in clinical practice Gut 69 2020 801 810 32047093
- [14]Lopetuso L.R. Deleu S. Godny L. Petito V. Puca P. Facciotti F. The first international Rome consensus conference on gut microbiota and faecal microbiota transplantation in inflammatory bowel disease Gut 72 2023 1642 1650 PMC10423477 37339849
- [15]Zhang S Chen Q Kelly CR Kassam Z Qin H Li N Donor screening for fecal microbiota transplantation in China: Evaluation of 8483 candidates Gastroenterology 162 2022 966 968.e3 34752816
- [16]National Institute of Hospital Administration, Society of Parenteral and Enteral Nutrition, Chinese Medical Association, Interstinal Microecology Cooperative Group, Chinese Society for Parenteral and Enteral Nutrition Expert consensus on clinical application management of fecal microbiota transplantation (2022 edition). Chin J Gastrointest Surg 25 2022 747 756 (in Chinese) 36117364
- [17]Wang LP Zhou SX Wang X Lu QB Shi LS Ren X Etiological, epidemiological, and clinical features of acute diarrhea in China Nat Commun 12 2021 2464 PMC8085116 33927201
- [18]Lin Q Li Z Lu L Xu H Lou E Chen A Budesonide, an anti-inflammatory drug, exacerbate Clostridioides difficile colitis in mice Biomed Pharmacother 167 2023 115489 37713991
- [19]Yap CX Henders AK Alvares GA Wood DLA Krause L Tyson GW Autism-related dietary preferences mediate autism-gut microbiome associations Cell 184 2021 5916 5931.e17 34767757
- [20]Kotsiliti E. Gut microbiome and autism spectrum disorder Nat Rev Gastroenterol Hepatol 19 2022 6 34857938
- [22]Buffington SA Dooling SW Sgritta M Noecker C Murillo OD Felice DF Dissecting the contribution of host genetics and the microbiome in complex behaviors Cell 184 2021 1740 1756.e16 PMC8996745 33705688
- [23]Chen Y. Xueying Z. Jiaqu C. Qiyi C. Huanlong Q. Ning L. FTACMT study protocol: a multicentre, double-blind, randomised, placebo-controlled trial of faecal microbiota transplantation for autism spectrum disorder BMJ Open 12 2022 e051613 PMC8804636 35105621
- [24]Porcari S. Benech N. Valles-Colomer M. Segata N. Gasbarrini A. Cammarota G. Key determinants of success in fecal microbiota transplantation: from microbiome to clinic Cell Host Microbe 31 2023 712 733 37167953
- [26]Duvallet C. Gibbons S.M. Gurry T. Irizarry R.A. Alm E.J. Meta-analysis of gut microbiome studies identifies disease-specific and shared responses Nat Commun 8 2017 1784 PMC5716994 29209090
- [27]Wilson B.C. Vatanen T. Cutfield W.S. O'Sullivan J.M. The super-donor phenomenon in fecal microbiota transplantation Front Cell Infect Microbiol 9 2019 2 PMC6348388 30719428
- [29]Haifer C. Luu L.D.W. Paramsothy S. Borody T.J. Leong R.W. Kaakoush N.O. Microbial determinants of effective donors in faecal microbiota transplantation for UC Gut 72 2023 90 100 35879048
- [30]Paramsothy S Nielsen S Kamm MA Deshpande NP Faith JJ Clemente JC Specific bacteria and metabolites associated with response to fecal microbiota transplantation in patients with ulcerative colitis Gastroenterology 156 2019 1440 1454.e2 30529583
- [31]Wilson B.C. Vatanen T. Jayasinghe T.N. Leong K.S.W. Derraik J.G.B. Albert B.B. Strain engraftment competition and functional augmentation in a multi-donor fecal microbiota transplantation trial for obesity Microbiome 9 2021 107 PMC8120839 33985595
- [32]Levast B. Fontaine M. Nancey S. Dechelotte P. Doré J. Lehert P. Single-donor and pooling strategies for fecal microbiota transfer product preparation in ulcerative colitis: A systematic review and meta-analysis Clin Transl Gastroenterol 14 2023 e00568 PMC10208705 37232579
- [33]Hu J. Amor D.R. Barbier M. Bunin G. Gore J. Emergent phases of ecological diversity and dynamics mapped in microcosms Science 378 2022 85 89 36201585
- [34]Cheng AG Ho PY Aranda-Díaz A Jain S Yu FB Meng X Design, construction, and in vivo augmentation of a complex gut microbiome Cell 185 2022 3617 3636.e19 PMC9691261 36070752
- [36]Sims MD Khanna S Feuerstadt P Louie TJ Kelly CR Huang ES Safety and tolerability of SER-109 as an investigational microbiome therapeutic in adults with recurrent Clostridioides difficile infection: A phase 3, open-label, single-arm trial JAMA Netw Open 6 2023 e2255758 PMC9926325 36780159
- [37]Morton J.T. Jin D.-M. Mills R.H. Shao Y. Rahman G. McDonald D. Multi-level analysis of the gut–brain axis shows autism spectrum disorder-associated molecular and microbial profiles Nat Neurosci 26 2023 1208 1217 PMC10322709 37365313
- [38]Sun WL Hua S Li XY Shen L Wu H Ji HF. Microbially produced vitamin B12 contributes to the lipid-lowering effect of silymarin Nat Commun 14 2023 477 PMC9887073 36717576
- [39]Smillie CS Sauk J Gevers D Friedman J Sung J Youngster I Strain tracking reveals the determinants of bacterial engraftment in the human gut following fecal microbiota transplantation Cell Host Microbe 23 2018 229 240.e5 PMC8318347 29447696
- [40]Gupta V.K. Kim M. Bakshi U. Cunningham K.Y. Davis J.M. Lazaridis K.N. A predictive index for health status using species-level gut microbiome profiling Nat Commun 11 2020 4635 PMC7492273 32934239
- [41]Zhang B. Yang L. Ning H. Cao M. Chen Z. Chen Q. A matching strategy to guide donor selection for ulcerative colitis in fecal microbiota transplantation: meta-analysis and analytic hierarchy process Microbiol Spectr 11 2023 e0215921 PMC9927247 36472435
- [42]He R. Li P. Wang J. Cui B. Zhang F. Zhao F. The interplay of gut microbiota between donors and recipients determines the efficacy of fecal microbiota transplantation Gut Microb 14 2022 2100197 PMC9302524 35854629
- [43]Bolyen E. Rideout J.R. Dillon M.R. Bokulich N.A. Abnet C.C. Al-Ghalith G.A. Reproducible, interactive, scalable and extensible microbiome data science using QIIME 2 Nat Biotechnol 37 2019 852 857 PMC7015180 31341288
- [44]Schloss P.D. Westcott S.L. Ryabin T. Hall J.R. Hartmann M. Hollister E.B. Introducing mothur: Open-source, platform-independent, community-supported software for describing and comparing microbial communities Appl Environ Microbiol 75 2009 7537 7541 PMC2786419 19801464
- [45]Watson M. McMurdie P.J. Holmes S. phyloseq: An R package for reproducible interactive analysis and graphics of microbiome census data PLoS One 8 2013 e61217 PMC3632530 23630581
- [46]Blanco-Míguez A. Beghini F. Cumbo F. McIver L.J. Thompson K.N. Zolfo M. Extending and improving metagenomic taxonomic profiling with uncharacterized species using MetaPhlAn 4 Nat Biotechnol 41 2023 1633 1644 PMC10635831 36823356
- [47]Pasolli E Asnicar F Manara S Zolfo M Karcher N Armanini F Extensive unexplored human microbiome diversity revealed by over 150,000 genomes from metagenomes spanning age, geography, and lifestyle Cell 176 2019 649 662.e20 PMC6349461 30661755
- [49]Valles-Colomer M. Blanco-Míguez A. Manghi P. Asnicar F. Dubois L. Golzato D. The person-to-person transmission landscape of the gut and oral microbiomes Nature 614 2023 125 135 PMC9892008 36653448
- [50]Aggarwala V. Mogno I. Li Z. Yang C. Britton G.J. Chen-Liaw A. Precise quantification of bacterial strains after fecal microbiota transplantation delineates long-term engraftment and explains outcomes Nat Microbiol 6 2021 1309 1318 PMC8993687 34580445
- [51]Podlesny D. Arze C. Dörner E. Verma S. Dutta S. Walter J. Metagenomic strain detection with SameStr: Identification of a persisting core gut microbiota transferable by fecal transplantation Microbiome 10 2022 53 PMC8951724 35337386
- [52]Debray R. Herbert R.A. Jaffe A.L. Crits-Christoph A. Power M.E. Koskella B. Priority effects in microbiome assembly Nat Rev Microbiol 20 2022 109 121 34453137
- [53]Palmer J.D. Foster K.R. Bacterial species rarely work together Science 376 2022 581 582 35511986
- [54]Venturelli O.S. Carr A.V. Fisher G. Hsu R.H. Lau R. Bowen B.P. Deciphering microbial interactions in synthetic human gut microbiome communities Mol Syst Biol 14 2018 e8157 PMC6011841 29930200
- [56]Paone P. Cani P.D. Mucus barrier, mucins and gut microbiota: the expected slimy partners? Gut 69 2020 2232 2243 PMC7677487 32917747
- [57]Isaac S. Scher J.U. Djukovic A. Jiménez N. Littman D.R. Abramson S.B. Short- and long-term effects of oral vancomycin on the human intestinal microbiota J Antimicrob Chemother 72 2017 128 136 PMC5161046 27707993
- [58]Shen TCD Daniel SG Patel S Kaplan E Phung L Lemelle-Thomas K The mucosally-adherent rectal microbiota contains features unique to alcohol-related cirrhosis Gut Microb 13 2021 1987781 PMC8583005 34747331
- [59]Zeise K.D. Woods R.J. Huffnagle G.B. Interplay between Candida albicans and lactic acid bacteria in the gastrointestinal tract: impact on colonization resistance, microbial carriage, opportunistic infection, and host immunity Clin Microbiol Rev 34 2021 e0032320 PMC8404691 34259567
- [60]Koh A. De Vadder F. Kovatcheva-Datchary P. Bäckhed F. From dietary fiber to host physiology: Short-chain fatty acids as key bacterial metabolites Cell 165 2016 1332 1345 27259147
- [61]Browne H.P. Almeida A. Kumar N. Vervier K. Adoum A.T. Viciani E. Host adaptation in gut Firmicutes is associated with sporulation loss and altered transmission cycle Genome Biol 22 2021 204 PMC8340488 34348764
- [62]Nicholson J.K. Holmes E. Kinross J. Burcelin R. Gibson G. Jia W. Host-gut microbiota metabolic interactions Science 336 2012 1262 1267 22674330
- [68]Zhang SL Mao YQ Zhang ZY Li ZM Kong CY Chen HL Pectin supplement significantly enhanced the anti-PD-1 efficacy in tumor-bearing mice humanized with gut microbiota from patients with colorectal cancer Theranostics 11 2021 4155 4170 PMC7977465 33754054
- [69]Ley R.E. Turnbaugh P.J. Klein S. Gordon J.I. Microbial ecology: Human gut microbes associated with obesity Nature 444 2006 1022 1023 17183309
- [70]Li J. Wei H. Establishment of an efficient germ-free animal system to support functional microbiome research Sci China Life Sci 62 2019 1400 1403 31559564
- [71]Tayfun U. Germ-free animal experiments in the gut microbiota studies Curr Opin Pharmacol 49 2019 6 10 31051390
- [72]Yang J. Zhang Z. Xie Z. Bai L. Xiong P. Chen F. Metformin modulates microbiota-derived inosine and ameliorates methamphetamine-induced anxiety and depression-like withdrawal symptoms in mice Biomed Pharmacother 149 2022 112837 35339829
- [73]Blacher E. Bashiardes S. Shapiro H. Rothschild D. Mor U. Dori-Bachash M. Potential roles of gut microbiome and metabolites in modulating ALS in mice Nature 572 2019 474 480 31330533
- [76]Kawanabe-Matsuda H. Takeda K. Nakamura M. Makino S. Karasaki T. Kakimi K. Dietary lactobacillus-derived exopolysaccharide enhances immune-checkpoint blockade therapy Cancer Discov 12 2022 1336 1355 PMC9662940 35180303
Cited by
Sorted by citations
The gut–brain axis in early Parkinson’s disease: from prodrome to prevention
Oliver, P. J., Civitelli, L., & Hu, M. T. (2025) · Journal of Neurology · doi:10.1007/s00415-025-13138-5 · Cited by 42 · see citing works
Sliti, A., Kim, R.-H., Lee, D., & Shin, J.-H. (2025) · Microbial Pathogenesis · doi:10.1016/j.micpath.2025.107405 · Cited by 5 · see citing works
- Authors
- Tian, H., Wang, X., Fang, Z., Li, L., Wu, C., Bi, D., Li, N., Chen, Q., & Qin, H.
- Affiliations
- Tongji University (CN)
- Corresponding author
- Chen, Qiyi
- Qin, Huanlong
- Venue
- hLife
- Publisher
- Elsevier BV
- Published
- 2024-06
- Volume
- 2
- Issue
- 6
- Pages
- 269-283
- ISSN
- 2949-9283 (ISSN-L)
- PMC
- PMC13681575
- OpenAlex
- W4391474400
- Cited by
- 56
- References
- 17
- Citations by year
- 2026: 19 · 2025: 33 · 2024: 4
- FWCI
- 2.29
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- hLife (publishedVersion, cc-by-nc-nd)
- PubMed Central (publishedVersion, cc-by-nc-nd)
- PubMed (publishedVersion)
- Funders
- Shanghai Municipal Health Commission (19YF1431000, ZHYY-ZXYJHZX-202105)
- National Natural Science Foundation of China (81972221, 81730102, 82300753)
- China Postdoctoral Science Foundation (81730102, 81972221, 202105, 2022M722412)
- Science and Technology Commission of Shanghai Municipality (YDZX20213100003690, 19YF1431000)
- Tongji University (2021SYPDRC045)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Gut microbiota and health
- Health Sciences › Medicine › Infectious Diseases › Clostridium difficile and Clostridium perfringens research
- Health Sciences › Medicine › Gastroenterology › Gastrointestinal motility and disorders
- Keywords
- fecal microbiota transplantation, gut microbiota, donor selection, donor-recipient matching, Clostridium difficile infection, intestinal inflammation, extraintestinal diseases, recipient management
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