The DOI matches its Crossref record; 61 of the 64 references it cites were found in a registry or an index.
Cancer associates with risk and severe events of COVID ‐19: A systematic review and meta‐analysis
Open accessAbstract
Evidence is mounting to indicate that cancer patients may have more likelihood of having coronavirus disease 2019 (COVID-19) but lack consistency. A robust estimate is urgently needed to convey appropriate information to the society and the public, in the time of ongoing COVID-19 pandemic. We performed a systematic review and meta-analysis through a comprehensive literature search in major databases in English and Chinese, and two investigators conducted publication selection and data extraction independently. A meta-analysis was used to obtain estimates of pooled prevalence of cancer in patients with COVID-19 and determine the association of cancer with severe events, after assessment of potential heterogeneity, publication bias, and correction for the estimates when necessary. Total 38 studies comprising 7094 patients with COVID-9 were included; the pooled prevalence of cancer was estimated at 2.3% (95% confidence limit [CL] [0.018, 0.029]; P < .001) overall and 3.2% (95% CL [0.023, 0.041]; P < .001) in Hubei province; the corresponding estimates were 1.4% and 1.9% after correction for publication bias; cancer was significantly associated with the events of severe cases (odds ratio [OR] = 2.20, 95% CL [1.53, 3.17]; P < .001) and death (OR = 2.97, 95% CL [1.48, 5.96]; P = .002) in patients with COVID-19, there was no significant heterogeneity and a minimal publication bias. We conclude that cancer comorbidity is associated with the risk and severe events of COVID-19; special measures should be taken for individuals with cancer.
Overview
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
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?
In the citing paper
“This is particularly true of older adults with cancer, who may be among the most vulnerable to the effects of COVID-19 due to their immunocompromised status and increased presence of comorbidities [1,2,3,4,5].”
From The Psychosocial Impact of COVID-19 on Older Adults with Cancer: A Rapid Review (2022) · cites this paper as [4]
In the citing paper
“Older adults diagnosed with both cancer and COVID-19 face increased mortality, hospitalization, and ICU admission [3,4,5].”
From The Psychosocial Impact of COVID-19 on Older Adults with Cancer: A Rapid Review (2022) · cites this paper as [4]
Citations
Cites
Preferred Reporting Items for Systematic Reviews and Meta-Analyses: the PRISMA statement
Moher, D., Liberati, A., Tetzlaff, J., Altman, D. G., & for the PRISMA Group (2009) · BMJ · doi:10.1136/bmj.b2535 · Cited by 83,823
Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China
Huang, C., Wang, Y., Li, X., Ren, L., Zhao, J., Hu, Y., Zhang, L., Fan, G., Xu, J., Gu, X., et al. (2020) · The Lancet · doi:10.1016/s0140-6736(20)30183-5 · Cited by 48,884
Self-citationPreferred reporting items for systematic reviews and meta-analyses: the PRISMA Statement.
(2009) · PubMed Central · Cited by 44,859
Quantifying heterogeneity in a meta‐analysis
Higgins, J. P. T., & Thompson, S. G. (2002) · Statistics in Medicine · doi:10.1002/sim.1186 · Cited by 36,763
Clinical characteristics of coronavirus disease 2019 in China
Guan, W.-J., Ni, Z.-Y., Hu, Y., Liang, W.-H., Ou, C.-Q., He, J.-X., Liu, L., Shan, H., Lei, C.-L., Hui, D. S. C., et al. (2020) · New England Journal of Medicine · doi:10.1056/nejmoa2002032 · Cited by 30,246
Zhou, F., Yu, T., Du, R., Fan, G., Liu, Y., Liu, Z., Xiang, J., Wang, Y., Song, B., Gu, X., et al. (2020) · The Lancet · doi:10.1016/s0140-6736(20)30566-3 · Cited by 27,263
Chen, N., Zhou, M., Dong, X., Qu, J., Gong, F., Han, Y., Qiu, Y., Wang, J., Liu, Y., Wei, Y., et al. (2020) · The Lancet · doi:10.1016/s0140-6736(20)30211-7 · Cited by 21,415
Wang, D., Hu, B., Hu, C., Zhu, F., Liu, X., Zhang, J., Wang, B., Xiang, H., Cheng, Z., Xiong, Y., et al. (2020) · JAMA · doi:10.1001/jama.2020.1585 · Cited by 20,148
La certeza de lo impredecible: Cultura Educación y Sociedad en tiempos de COVID19
Martínez González, M. (2020) · DSPACE System - Metalibrary (University of the Coast) · Cited by 18,463
Wu, Z., & McGoogan, J. M. (2020) · JAMA · doi:10.1001/jama.2020.2648 · Cited by 17,016
Early transmission dynamics in Wuhan, China, of novel coronavirus-infected pneumonia
Li, Q., Guan, X., Wu, P., Wang, X., Zhou, L., Tong, Y., Ren, R., Leung, K. S. M., Lau, E. H. Y., Wong, J. Y., et al. (2020) · New England Journal of Medicine · doi:10.1056/nejmoa2001316 · Cited by 16,575
Self-citationDuval, S., & Tweedie, R. (2000) · Biometrics · doi:10.1111/j.0006-341x.2000.00455.x · Cited by 14,099
Yang, X., Yu, Y., Xu, J., Shu, H., Xia, J., Liu, H., Wu, Y., Zhang, L., Yu, Z., Fang, M., et al. (2020) · The Lancet Respiratory Medicine · doi:10.1016/s2213-2600(20)30079-5 · Cited by 10,066
Pathological findings of COVID-19 associated with acute respiratory distress syndrome
Xu, Z., Shi, L., Wang, Y., Zhang, J., Huang, L., Zhang, C., Liu, S., Zhao, P., Liu, H., Zhu, L., et al. (2020) · The Lancet Respiratory Medicine · doi:10.1016/s2213-2600(20)30076-x · Cited by 8,545
Self-citationWu, C., Chen, X., Cai, Y., Xia, J., Zhou, X., Xu, S., Huang, H., Zhang, L., Zhou, X., Du, C., et al. (2020) · JAMA Internal Medicine · doi:10.1001/jamainternmed.2020.0994 · Cited by 8,249
Neurologic manifestations of hospitalized patients with coronavirus disease 2019 in Wuhan, China
Mao, L., Jin, H., Wang, M., Hu, Y., Chen, S., He, Q., Chang, J., Hong, C., Zhou, Y., Wang, D., et al. (2020) · JAMA Neurology · doi:10.1001/jamaneurol.2020.1127 · Cited by 7,166
Cancer Immunoediting: Integrating Immunity’s Roles in Cancer Suppression and Promotion
Schreiber, R. D., Old, L. J., & Smyth, M. J. (2011) · Science · doi:10.1126/science.1203486 · Cited by 6,474
Cancer patients in SARS-CoV-2 infection: a nationwide analysis in China
Liang, W., Guan, W., Chen, R., Wang, W., Li, J., Xu, K., Li, C., Ai, Q., Lu, W., Liang, H., et al. (2020) · The Lancet Oncology · doi:10.1016/s1470-2045(20)30096-6 · Cited by 4,384
Clinical characteristics of 140 patients infected with SARS‐CoV‐2 in Wuhan, China
Zhang, J., Dong, X., Cao, Y., Yuan, Y.-D., Yang, Y., Yan, Y., Akdiş, C. A., & Gao, Y. (2020) · Allergy · doi:10.1111/all.14238 · Cited by 4,088
Clinical characteristics of 113 deceased patients with coronavirus disease 2019: retrospective study
Chen, T., Wu, D., Chen, H., Yan, W., Yang, D., Chen, G., Ma, K., Xu, D., Yu, H., Wang, H., et al. (2020) · BMJ · doi:10.1136/bmj.m1091 · Cited by 3,903
Self-citationComorbidity and its impact on 1590 patients with covid-19 in China: a nationwide analysis
Guan, W.-J., Liang, W.-H., Zhao, Y., Liang, H.-R., Chen, Z.-S., Li, Y.-M., Liu, X.-Q., Chen, R.-C., Tang, C.-L., Wang, T., et al. (2020) · European Respiratory Journal · doi:10.1183/13993003.00547-2020 · Cited by 3,680
Radiological findings from 81 patients with COVID-19 pneumonia in Wuhan, China: a descriptive study
Shi, H., Han, X., Jiang, N., Cao, Y., Alwalid, O., Gu, J., Fan, Y., & Zheng, C. (2020) · The Lancet Infectious Diseases · doi:10.1016/s1473-3099(20)30086-4 · Cited by 3,664
Risk factors for severity and mortality in adult COVID-19 inpatients in Wuhan
Li, X., Xu, S., Yu, M., Wang, K., Tao, Y., Zhou, Y., Shi, J. C., Zhou, M., Wu, B., Yang, Z., et al. (2020) · Journal of Allergy and Clinical Immunology · doi:10.1016/j.jaci.2020.04.006 · Cited by 2,273
Self-citationCurrent cancer situation in China: good or bad news from the 2018 Global Cancer Statistics?
Feng, R., Zong, Y., Cao, S., & Xu, R. (2019) · 癌症:英文版 · doi:10.1186/s40880-019-0368-6 · Cited by 1,646
Clinical characteristics of novel coronavirus cases in tertiary hospitals in Hubei Province
Liu, K., Fang, Y.-Y., Deng, Y., Liu, W. Y., Wang, M., Ma, J.-P., Xiao, W. L., Wang, Y.-N., Zhong, M.-H., Li, C.-H., et al. (2020) · Chinese Medical Journal · doi:10.1097/cm9.0000000000000744 · Cited by 1,433
Does comorbidity increase the risk of patients with COVID-19: evidence from meta-analysis
Wang, B., Li, R., Lu, Z., & Huang, Y. (2020) · Aging · doi:10.18632/aging.103000 · Cited by 1,304
Liu, W. Y., Tao, Z.-W., Wang, L., Yuan, M.-L., Liu, K., Zhou, L., Wei, S., Deng, Y., Liu, J., Liu, H., et al. (2020) · Chinese Medical Journal · doi:10.1097/cm9.0000000000000775 · Cited by 1,112
Clinical Features of 69 Cases With Coronavirus Disease 2019 in Wuhan, China
Wang, Z., Yang, B., Li, Q., Wen, L., & Zhang, R. (2020) · Clinical Infectious Diseases · doi:10.1093/cid/ciaa272 · Cited by 1,063
Age-dependent dysregulation of innate immunity
Shaw, A. C., Goldstein, D. R., & Montgomery, R. R. (2013) · Nature Reviews Immunology · doi:10.1038/nri3547 · Cited by 1,061
Yang, W., Cao, Q., Qin, L., Wang, X., Cheng, Z., Pan, A., Dai, J., Sun, Q., Zhao, F., Qu, J., et al. (2020) · Journal of Infection · doi:10.1016/j.jinf.2020.02.016 · Cited by 1,003
Clinical Features and Treatment of COVID-19 Patients in Northeast Chongqing
Wan, S., Xiang, Y., Fang, W., Zheng, Y., Li, B., Hu, Y., Lang, C., Huang, D., Sun, Q., Xiong, Y., et al. (2020) · Journal of Medical Virology · doi:10.1002/jmv.25783 · Cited by 982
Clinical Characteristics of Refractory Coronavirus Disease 2019 in Wuhan, China
Mo, P., Xing, Y., Xiao, Y., Deng, L., Zhao, Q., Wang, H., Xiong, Y., Cheng, Z., Gao, S., Liang, K., et al. (2020) · Clinical Infectious Diseases · doi:10.1093/cid/ciaa270 · Cited by 871
COVID-19 with Different Severities: A Multicenter Study of Clinical Features
Feng, Y., Ling, Y., Bai, T., Xie, Y., Huang, J., Li, J., Xiong, W., Yang, D., Chen, R., Lu, F., et al. (2020) · American Journal of Respiratory and Critical Care Medicine · doi:10.1164/rccm.202002-0445oc · Cited by 845
Self-citationClinical progression of patients with COVID-19 in Shanghai, China
Chen, J., Qi, T., Liu, L., Ling, Y., Qian, Z., Li, T., Li, F., Xu, Q., Zhang, Y., Xu, S., et al. (2020) · Journal of Infection · doi:10.1016/j.jinf.2020.03.004 · Cited by 801
Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2
Xu, X., Yu, C., Qu, J. T., Zhang, L., Jiang, S., Huang, D., Chen, B., Zhang, Z., Guan, W., Ling, Z., et al. (2020) · European Journal of Nuclear Medicine and Molecular Imaging · doi:10.1007/s00259-020-04735-9 · Cited by 792
Clinical features and short-term outcomes of 221 patients with COVID-19 in Wuhan, China
Zhang, G., Hu, C., Luo, L., Fang, F., Chen, Y., Li, J., Peng, Z., & Pan, H. (2020) · Journal of Clinical Virology · doi:10.1016/j.jcv.2020.104364 · Cited by 699
Risk factors for disease severity, unimprovement, and mortality in COVID-19 patients in Wuhan, China
Zhang, J., Wang, X., Jia, X., Li, J., Hu, K., Chen, G., Wei, J., Gong, Z., Zhou, C., Yu, H., et al. (2020) · Clinical Microbiology and Infection · doi:10.1016/j.cmi.2020.04.012 · Cited by 685
Deng, Y., Liu, W., Liu, K., Fang, Y.-Y., Shang, J., Zhou, L., Wang, K., Leng, F., Wei, S., Chen, L., et al. (2020) · Chinese Medical Journal · doi:10.1097/cm9.0000000000000824 · Cited by 657
[Report of cancer epidemiology in China, 2015].
Zheng, R., Sun, K., Zhang, S., Zeng, H., Zou, X., Chen, R., Gu, X., Wei, W., & He, J. (2019) · PubMed · doi:10.3760/cma.j.issn.0253-3766.2019.01.005 · Cited by 643
Wu, J., Liu, J., Zhao, X., Liu, C., Wang, W., Wang, D., Xu, W., Zhang, C., Yu, J., Jiang, B., et al. (2020) · Clinical Infectious Diseases · doi:10.1093/cid/ciaa199 · Cited by 633
Chen, L., Liu, W., Qi, Z., Xu, K., Ye, G., Wu, W.-C., Sun, Z., Liu, F., Wu, K., Zhong, B., et al. (2020) · Emerging Microbes & Infections · doi:10.1080/22221751.2020.1725399 · Cited by 570
Cao, J., Tu, W., Cheng, W., Yu, L., Liu, Y., Hu, X., & Liu, Q. (2020) · Clinical Infectious Diseases · doi:10.1093/cid/ciaa243 · Cited by 497
Russell, B. A., Moss, C. L., George, G., Santaolalla, A., Cope, A. P., Papa, S., & Hemelrijck, M. V. (2020) · ecancermedicalscience · doi:10.3332/ecancer.2020.1022 · Cited by 440
Risk of COVID-19 for patients with cancer
Xia, Y., Jin, R., Zhao, J., Li, W., & Shen, H. (2020) · The Lancet Oncology · doi:10.1016/s1470-2045(20)30150-9 · Cited by 436
Self-citationCOVID-19 and Cancer: Lessons From a Pooled Meta-Analysis
Desai, A. P., Sachdeva, S., Parekh, T., & Desai, R. (2020) · JCO Global Oncology · doi:10.1200/go.20.00097 · Cited by 310
Wang, K., Zuo, P., Liu, Y., Zhang, M., Zhao, X., Xie, S., Zhang, H., Chen, X., & Liu, C. (2020) · Clinical Infectious Diseases · doi:10.1093/cid/ciaa538 · Cited by 308
Liang, W., Guan, W., Li, C., Li, Y., Liang, H.-R., Zhao, Y., Liu, X.-Q., Sang, L., Chen, R.-C., Tang, C., et al. (2020) · European Respiratory Journal · doi:10.1183/13993003.00562-2020 · Cited by 302
Self-citationReport of incidence and mortality in China Cancer Registries, 2008
Chen, W., Zheng, R., Zhang, S.-W., Li, N., Zhao, P., Li, G.-L., Liang-you, W., & He, J. (2012) · Chinese Journal of Cancer Research · doi:10.1007/s11670-012-0171-2 · Cited by 284
Wang, R., Pan, M., Zhang, X., Han, M., Fan, X., Zhao, F., Miao, M., Xu, J., Guan, M., Xia, D., et al. (2020) · International Journal of Infectious Diseases · doi:10.1016/j.ijid.2020.03.070 · Cited by 243
Huang, Y., Tu, M., Wang, S., Chen, S., Zhou, W., Chen, D., Zhou, L., Wang, M., Zhao, Y., Zeng, W., et al. (2020) · Travel Medicine and Infectious Disease · doi:10.1016/j.tmaid.2020.101606 · Cited by 229
Immune-epidemiological parameters of the novel coronavirus – a perspective
Saghazadeh, A., & Rezaei, N. (2020) · Expert Review of Clinical Immunology · doi:10.1080/1744666x.2020.1750954 · Cited by 228
Won, J., Lee, S., Park, M., Kim, T. Y., Park, M. G., Choi, B. Y., Kim, D.-W., Chang, H., Kim, V. N., & Lee, C. J. (2020) · Experimental Neurobiology · doi:10.5607/en20009 · Cited by 202
Hospitalization and Critical Care of 109 Decedents with COVID-19 Pneumonia in Wuhan, China
Du, R., Liu, L., Yin, W., Wang, W., Guan, L., Yuan, M.-L., Li, Y.-L., Hu, Y., Li, X., Sun, B., et al. (2020) · Annals of the American Thoracic Society · doi:10.1513/annalsats.202003-225oc · Cited by 198
Liu, C., Jiang, Z. C., Shao, C. X., Zhang, H. G., Yue, H. M., Chen, Z. H., Ma, B. Y., Liu, W. Y., Huang, H. H., Yang, J., et al. (2020) · PubMed · doi:10.3760/cma.j.issn.1007-3418.2020.02.003 · Cited by 116
Luo, Y., Liu, C., Guan, T., Li, Y., Lai, Y., Li, F., Zhao, H., Maimaiti, T., & Zeyaweiding, A. (2018) · Hypertension Research · doi:10.1038/s41440-018-0166-6 · Cited by 104
ACE2 polymorphisms associated with cardiovascular risk in Uygurs with type 2 diabetes mellitus
Liu, C., Li, Y., Guan, T., Lai, Y., Shen, Y., Zeyaweiding, A., Zhao, H., Li, F., & Maimaiti, T. (2018) · Cardiovascular Diabetology · doi:10.1186/s12933-018-0771-3 · Cited by 93
Luo, Y., Liu, C., Guan, T., Li, Y., Lai, Y., Li, F., Zhao, H., Maimaiti, T., & Zeyaweiding, A. (2019) · Hypertension Research · doi:10.1038/s41440-019-0205-y · Cited by 72
Wang, L., Duan, Y., Zhang, W., Liang, J., Xu, J., Zhang, Y., Wu, C., Xu, Y., & Li, H. (2020) · Clinical Epidemiology · doi:10.2147/clep.s249903 · Cited by 55
Sereno, M., Gutiérrez‐Gutiérrez, G., Sandoval, C. P., Falagán, S., Jimenez-Gordo, A. M., Merino, M., López-Menchaca, R., Martínez-Martín, P., Roa, S., & Casado, E. (2020) · Lung Cancer · doi:10.1016/j.lungcan.2020.04.029 · Cited by 12
Clinical characteristics of 74 hospitalized patients with COVID-19
Wei, Z., Wei, H., Li, T., Li, A., Wen, P., Jin, R., Liang, L., & Hu, Z. (2020) · Journal of Capital Medical University · doi:10.3969/j.issn.1006-7795.2020.02.003 · Cited by 12
Cancer and COVID‐19: A call for comments
Watson, M., Lam, W., Pirl, W. F., & Fielding, R. (2020) · Psycho-Oncology · doi:10.1002/pon.5384 · Cited by 1
Flagged first, then by citations
3 of the 64 references couldn’t be matched to a known paper.
Research works printed but not linked: 6
- Fang XW, 2020, Clinical characteristics and treatment analysis of 79 patients infected with SARS‐CoV‐2, Chin Pharmacol Bull, 36, 453
- Li D, 2020, Clinical characteristics of 80 patients with COVID‐19 in Zhozhou city, Chin J Infect Control, 19, 227
- Li YL, 2020, Comparative study for clinical features between COVID‐19 patients with conventional type and heavy/critical type, Pract J Cardiac Cereb Pneumal Vasc Dis, 28, 14
- Sun DF, 2020, Clinical analysis of 30 patients infected with SARS‐CoV‐2, Zhejiang Clin Med, 22, 354
- Wang F, 2020, Clinical characteristics of 29 patients with COVID‐19 in Ningxia city, Ningxia Med J, 42, 263
- Tuo JY, 2016, Cancer incidence and mortality in cancer registries in Hubei Province, 2012, Cancer Res Prev Treat, 43, 974
Cited by
Sorted by citations
Mesas, A. E., Cavero‐Redondo, I., Álvarez‐Bueno, C., Cabrera, M. A. S., de Andrade, S. M., Sequí‐Domínguez, I., & Martínez‐Vizcaíno, V. (2020) · PLoS ONE · doi:10.1371/journal.pone.0241742 · Cited by 245
Treskova, M., Haas, L., Reda, S. A., Pilic, A., Borodova, A., Karimi, K., Koch, J., Nygren, T. M., Scholz, S. M., Schönfeld, V., et al. (2021) · BMC Medicine · doi:10.1186/s12916-021-02058-6 · Cited by 219
Galmiche, S., Nguyen, L. B. L., Tartour, É., de Lamballerie, X. N., Wittkop, L., Loubet, P., & Launay, O. (2021) · Clinical Microbiology and Infection · doi:10.1016/j.cmi.2021.09.036 · Cited by 207
Digital Health Applications in Oncology: An Opportunity to Seize
Parikh, R. B., Basen-Enquist, K. M., Bradley, C. J., Estrin, D. L., Levy, M. A., Lichtenfeld, J. L., Malin, B., McGraw, D., Meropol, N. J., Oyer, R. A., et al. (2022) · JNCI Journal of the National Cancer Institute · doi:10.1093/jnci/djac108 · Cited by 81
Li, H., Zhang, Y., Shu, H., Lv, W., Su, C., & Nie, F. (2021) · International Journal of Pharmaceutics · doi:10.1016/j.ijpharm.2021.121412 · Cited by 68
Metadata
- Authors
- Tian, Y., Qiu, X., Wang, C., Zhao, J., Jiang, X., Niu, W., Huang, J., & Zhang, F.
- Affiliations
- Beijing University of Chinese Medicine (CN)
- China-Japan Friendship Hospital (CN)
- Peking University (CN)
- Corresponding author
- Niu, Wenquan
- Huang, Jinchang
- Zhang, Fengyu
- Venue
- International Journal of Cancer
- Publisher
- Wiley
- Published
- 2020-08-15
- Volume
- 148
- Issue
- 2
- Pages
- 363-374
- ISSN
- 0020-7136 (ISSN-L)
- 1097-0215
- PMC
- PMC7404763
- OpenAlex
- W3042427819
- Cited by
- 129
- References
- 64
- Citations by year
- 2026: 3 · 2025: 7 · 2024: 6 · 2023: 22 · 2022: 42 · 2021: 41 · 2020: 7
- FWCI
- 3.01
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- International Journal of Cancer (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Natural Science Foundation of China (81573736)
- Topics
- Health Sciences › Medicine › Oncology › COVID-19 and healthcare impacts
- Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
- Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
- Keywords
- COVID-19 pandemic, cancer comorbidity, disease severity, mortality, risk factors, Hubei Province, publication bias
- MeSH terms
- COVID-19, SARS-CoV-2, Humans, Neoplasms, Risk Factors, Severity of Illness Index, Comorbidity, Prevalence, Risk Assessment, Pandemics
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