The DOI matches its Crossref record; 33 of the 33 references it cites were found in a registry or an index.
Circulating irisin levels as a predictive biomarker for sarcopenia: a cross-sectional community-based study
Open accessAbstract
Aim: Myokines are peptides released by the skeletal muscle, and have gained popularity as potential biomarkers for sarcopenia. Irisin is a recently identified myokine, but its role in pathological sarcopenia remains unclear. We investigated the validity and accuracy of circulating irisin levels as a potential biomarker for sarcopenia. Methods: We evaluated the anthropometrics, body composition, sarcopenia‐related parameters and serum irisin levels of 715 community‐dwelling Koreans. Sarcopenia was determined on the basis of the clinical diagnostic criteria of muscle atrophy and weakness, which were proposed by the Asian Working Group for Sarcopenia. Results: Circulating irisin levels were correlated with appendicular lean mass/height 2 (rmen = 0.275; rwomen = 0.321) and handgrip strength (rmen = 0.219; rwomen = 0.312) in both sexes (all P < 0.01). Furthermore, the mean circulating irisin levels were lower in the sarcopenia group than in the normal group (all P < 0.05). In the logistic regression models, the association between serum irisin concentration and incident sarcopenia persisted even after adjusting for potential confounders, such as sex, age and fat indices (odds ratio 0.20, 95% CI 0.07–0.60; P for trend <0.01). The predictive values of serum irisin for sarcopenia were <1.0 μg/mL in men and <1.16 μg/mL in women, with the area under the receiver operating characteristic curves of 0.87 (95% CI 0.77–0.99) and 0.68 (95% CI 0.55–0.81), respectively (all P < 0.01). Conclusions: A low level of circulating irisin is a sensitive marker for muscle weakness and atrophy. Irisin is a potential biomarker for muscle dysfunction that could help predict the onset of sarcopenia and provide new avenues for monitoring age‐related muscle changes. Geriatr Gerontol Int 2017; 17: 2266–2273.
Overview
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
Verification
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?
In the citing paper
“However, several studies have documented that the content of myostatin is upregulated while irisin is downregulated in sarcopenia (44).”
From Diabetes and Sarcopenic Obesity: Pathogenesis, Diagnosis, and Treatments (2020) · cites this paper as [44]
In the citing paper
“Production of myostatin, a growth-inhibiting myokine, is upregulated in sarcopenia64, whereas that of muscle-mass-stimulating irisin seems to be downregulated65.”
From Sarcopenic obesity in older adults: a clinical overview (2024) · cites this paper as [65]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Citations
Cites
Biomarkers and surrogate endpoints: Preferred definitions and conceptual framework
Biomarkers Definitions Working Group (2001) · Clinical Pharmacology & Therapeutics · doi:10.1067/mcp.2001.113989 · Cited by 6,771
A PGC1-α-dependent myokine that drives brown-fat-like development of white fat and thermogenesis
Boström, P., Wu, J., Jedrychowski, M. P., Korde, A., Ye, L., Lo, J. C., Rasbach, K. A., Boström, E. A., Choi, J. H., Long, J. Z., et al. (2012) · Nature · doi:10.1038/nature10777 · Cited by 4,810
Sarcopenia in Asia: Consensus Report of the Asian Working Group for Sarcopenia
Chen, L.-K., Liu, L.-K., Woo, J., Assantachai, P., Auyeung, T.-W., Bahyah, K. S., Chou, M.-Y., Chen, L.-Y., Hsu, P.-S., Krairit, O., et al. (2014) · Journal of the American Medical Directors Association · doi:10.1016/j.jamda.2013.11.025 · Cited by 4,051
Goodpaster, B. H., Park, S. W., Harris, T. B., Kritchevsky, S. B., Nevitt, M., Schwartz, A. V., Simonsick, E. M., Tylavsky, F. A., Visser, M., Newman, A. B., et al. (2006) · The Journals of Gerontology Series A: Biological Sciences and Medical Sciences · doi:10.1093/gerona/61.10.1059 · Cited by 3,083
Muscles, exercise and obesity: skeletal muscle as a secretory organ
Pedersen, B. K., & Febbraio, M. A. (2012) · Nature Reviews Endocrinology · doi:10.1038/nrendo.2012.49 · Cited by 2,909
Bioelectrical impedance analysis—part II: utilization in clinical practice
Kyle, U. G., Bosaeus, I., De Lorenzo, A. D., Deurenberg, P., Elia, M., Manuel Gómez, J., Lilienthal Heitmann, B., Kent-Smith, L., Melchior, J.-C., Pirlich, M., et al. (2004) · Clinical Nutrition · doi:10.1016/j.clnu.2004.09.012 · Cited by 2,350
Inflammatory markers and loss of muscle mass (sarcopenia) and strength
Schaap, L. A., Pluijm, S. M. F., Deeg, D. J. H., & Visser, M. (2006) · The American Journal of Medicine · doi:10.1016/j.amjmed.2005.10.049 · Cited by 1,047
Huh, J. Y., Panagiotou, G., Mougios, V., Brinkoetter, M., Vamvini, M. T., Schneider, B. E., & Mantzoros, C. S. (2012) · Metabolism · doi:10.1016/j.metabol.2012.09.002 · Cited by 1,040
FNDC5/irisin is not only a myokine but also an adipokine
Roca-Rivada, A., Castelao, C., Senin, L. L., Landrove, M. O., Baltar, J., Crujeiras, A. B., Seoane, L. M., Casanueva, F. F., & Pardo, M. (2013) · PLoS ONE · doi:10.1371/journal.pone.0060563 · Cited by 612
Review Article: Sarcopenia: Causes, Consequences, and Preventions
Marcell, T. J. (2003) · The Journals of Gerontology Series A: Biological Sciences and Medical Sciences · doi:10.1093/gerona/58.10.m911 · Cited by 536
Flagged first, then by citations
Cited by
Sorted by citations
Items 101–166 of 166
Bisphosphonates attenuate age‐related muscle decline in Caenorhabditis elegans
Slade, L., Bollen, S. E., Bass, J. J., Phillips, B. E., Smith, K., Wilkinson, D. J., Szewczyk, N. J., Atherton, P. J., & Etheridge, T. (2023) · Journal of Cachexia Sarcopenia and Muscle · doi:10.1002/jcsm.13335 · Cited by 8
Potential effect of Irisin on sarcopenia: a systematic review
Chen, Y., Qian, M., Gao, F., Li, G., Peng, K., Sun, Q., Sun, Y., Liu, G., Ge, Y., Yang, M., et al. (2025) · BMC Musculoskeletal Disorders · doi:10.1186/s12891-025-08767-w · Cited by 8
Glazachev, O. S., Zapara, M. A., Kryzhanovskaya, S. Y., Dudnik, E. N., Yumatov, E., & Susta, D. (2021) · Journal of Thermal Biology · doi:10.1016/j.jtherbio.2021.103067 · Cited by 8
Body composition and myokines in a cohort of patients with Becker muscular dystrophy
Barp, A., Carraro, E., Goggi, G., Lizio, A., Zanolini, A., Messina, C., Perego, S., Verdelli, C., Lombardi, G., Sansone, V., et al. (2022) · Muscle & Nerve · doi:10.1002/mus.27565 · Cited by 8
Picciotto, D., Macciò, L., Verzola, D., Baciga, F., Momentè, C., Russo, E., Viazzi, F. C., Battaglia, Y., & Esposito, P. B. (2024) · Kidney & Blood Pressure Research · doi:10.1159/000539489 · Cited by 9
Knapik, M., Kuna, J., Chmielewski, G., Jaśkiewicz, Ł., & Krajewska–Włodarczyk, M. (2025) · Journal of Clinical Medicine · doi:10.3390/jcm14186527 · Cited by 7
Ma, Y., Liu, Y., Zheng, J., Zheng, Z., & Li, J. (2025) · Aging Clinical and Experimental Research · doi:10.1007/s40520-025-03051-2 · Cited by 8
[Research progress on the correlation between sarcopenia and osteoarthritis].
Peng, H., & Zeng, Y. (2022) · PubMed Central · doi:10.7507/1002-1892.202209015 · Cited by 7
Ananthamohan, K., Jha, R. M., & Sharma, S. (2019) · Elsevier eBooks · doi:10.1016/b978-0-12-814259-2.00005-4 · Cited by 7
Sala, G., Cuffaro, L., Pozzi, F. E., Andreoni, S., Bazzini, C., Conti, E., Zoia, C., Beretta, S., Tremolizzo, L., Bellelli, G., et al. (2025) · Frontiers in Aging Neuroscience · doi:10.3389/fnagi.2025.1581892 · Cited by 8
Shi, H., Sun, W., Cao, X., Fan, X., Xie, W., Hao, X., Wang, S., Lu, J., Yan, Y., Luo, X., et al. (2025) · Cells · doi:10.3390/cells14211675 · Cited by 7
Luo, Y., Song, Y., Zeng, M., Li, B., Li, Y., & Dong, Z. (2025) · Ageing Research Reviews · doi:10.1016/j.arr.2025.102959 · Cited by 6
Xu, D., Jin, H., JinLin, Y., Zuo, Z., Ou, R., Hu, F., Pu, L., Dong, Y., Wu, M., Dong, B., et al. (2026) · Journal of Cachexia Sarcopenia and Muscle · doi:10.1002/jcsm.70188 · Cited by 6
Hart, D. A., Zernicke, R. F., & Shrive, N. G. (2022) · International Journal of Molecular Sciences · doi:10.3390/ijms23179949 · Cited by 6
Moghadam, B. H., Johne, M., Golestani, F., Lorenz, K., Asad, M., Maculewicz, E., & Mastalerz, А. (2023) · Biology of Sport · doi:10.5114/biolsport.2023.123894 · Cited by 5
Shi, Y., Zhang, Y., Zhang, Y., Li, L., Wang, L., & Fan, Y. (2025) · Biomacromolecules · doi:10.1021/acs.biomac.5c01700 · Cited by 5
Jürimäe, J., Purge, P., Remmel, L., Ereline, J., Kums, T., Kamandulis, S., Brazaitis, M., Venckūnas, T., & Pääsuke, M. (2022) · The Journal of Sports Medicine and Physical Fitness · doi:10.23736/s0022-4707.22.13949-6 · Cited by 5
Circulating Irisin Level as a Biomarker for Pure Aortic Stenosis and Aortic Valve Calcification
Wang, S., Li, J., Hu, P., Guo, Y., Liu, X., Wang, J.-A., & Chen, H. (2022) · Journal of Cardiovascular Translational Research · doi:10.1007/s12265-022-10327-9 · Cited by 5
Fan, Z., Wu, F., Wang, P., Wu, L., Zhang, J., Li, W., Pang, Q., & Zhang, A. (2025) · Kidney & Blood Pressure Research · doi:10.1159/000543214 · Cited by 4
State-of-the-art insights into myokines as biomarkers of sarcopenia: a literature review
Moussaoui, O. R. (2025) · International Journal of Physiology Pathophysiology and Pharmacology · doi:10.62347/rneq8696 · Cited by 4
Kim, Y., Song, H. J., Kim, D., Jeong, J., Park, K. H., Park, Y. S., Kim, J., & Noh, H. (2025) · Journal of Cachexia Sarcopenia and Muscle · doi:10.1002/jcsm.70172 · Cited by 6
Self-citationSarcopenic obesity in children
Zavyalova, A. N., Troshkina, M. E., Shcherbak, L. A., & Новикова, В. П. (2023) · Экспериментальная и клиническая гастроэнтерология · doi:10.31146/1682-8658-ecg-209-1-134-141 · Cited by 4
Alzoughool, F., Hourani, H. M. A., Atoum, M. F. M., Bateineh, S., shaikh, H. A., Al-Zghool, H., & Al-Shudifat, A.-E. (2021) · Nutrition and Healthy Aging · doi:10.3233/nha-200110 · Cited by 4
Mendez, J. L., Lanzi, C. R., Quan, Z., Chen, S., Krga, I., & Mackenzie, G. G. (2025) · Food & Function · doi:10.1039/d5fo01523e · Cited by 3
Liu, L., Cai, Y., Liu, D., Fang, R., Huang, H., Zou, M., Chen, B., Peng, J., & Hao, L. (2026) · Biomaterials Science · doi:10.1039/d5bm01061f · Cited by 3
Skrzep-Poloczek, B., Idzik, M., Michalczyk, K., Chełmecka, E., Kukla, M., Zalejska–Fiolka, J., Poloczek, J., Bogielski, B., Jochem, J., Nowak, D., et al. (2023) · Journal of Clinical Medicine · doi:10.3390/jcm12154881 · Cited by 3
Reduced irisin levels in patients with acromegaly
Şendur, S. N., Baykal, G., Fırlatan, B., Aydin, B., Lay, İ., Dağdelen, S., Alikaşifoğlu, M., & Erbas, T. A. (2022) · Hormone Molecular Biology and Clinical Investigation · doi:10.1515/hmbci-2022-0009 · Cited by 4
Cheng, Q., Wu, C., Guo, L., & Hu, J. (2022) · Frontiers in Endocrinology · doi:10.3389/fendo.2022.972238 · Cited by 4
Irisin, Brain-Derived Neurotrophic Factor (BDNF), and Redox Balance in Geriatric Dynapenia
Wojszel, A., Śliwowski, J., Rentflejsz, J., Rogalska, J., Brzoska, M. M., & Wojszel, Z. B. (2025) · Antioxidants · doi:10.3390/antiox14101268 · Cited by 2
Santo, R. C. D. E., dos Santos, L. P., Melo, G. L. R., Dubey, V. P., & Agostinis‐Sobrinho, C. (2025) · BMJ Open Sport & Exercise Medicine · doi:10.1136/bmjsem-2025-002617 · Cited by 2
Protective effects of irisin in sarcopenia: a promising treatment
Chen, Y., Li, G., Gao, F., Li, R., Yang, M., Ge, Y., & Wu, X. (2026) · Journal of Orthopaedic Translation · doi:10.1016/j.jot.2026.101090 · Cited by 2
Biomarkers of Sarcopenia: Current Status and Future Perspectives
Luo, B., Li, W., Zhang, Y., Liu, M. H., Zhang, K., Huang, S., & He, P. (2026) · Aging Medicine · doi:10.1002/agm2.70088 · Cited by 2
Impact of exercise-induced irisin on bones of osteoporotic male rat model
Moghazy, H. M., Mahmoud, A. A., Gebril, S. M., Foad, A. M., Refaei, R. A., & Abdel-Fadeil, M. R. (2023) · Gene Reports · doi:10.1016/j.genrep.2023.101804 · Cited by 2
The impact of dietary intervention on myokines: a narrative review
Assyov, Y. S., Chechev, K., Gateva, A., Karamfilova, V., Gatev, T., Popov, D., Naydenov, Y., Zaharieva, E., Konova, N., Yordanova, S., et al. (2024) · Pharmacia · doi:10.3897/pharmacia.71.e123805 · Cited by 2
Ouyang, F., Chen, S., Li, S., Liu, L., Guan, S., Yan, Z., Shumin, W., Zeng, Y., Liu, J., & Zhong, J. (2024) · International Journal of General Medicine · doi:10.2147/ijgm.s483793 · Cited by 2
Zhang, L., Peng, Y., Qie, Y., Guo, J., Kong, Y., Zhang, X., Li, Z., & Jia, H. (2025) · Applied Physiology, Nutrition, and Metabolism · doi:10.1139/apnm-2024-0473 · Cited by 3
Obesity, Myokines, and Metabolic Health
Malandrino, N., & Ahima, R. S. (2023) · Springer eBooks · doi:10.1007/978-3-031-40116-9_56 · Cited by 2
Garrett, J. M., McCormick, J. J., King, K. E., Meade, R. D., Boulay, P., Sigal, R. J., O’Connor, F. K., & Kenny, G. P. (2025) · Physiological Reports · doi:10.14814/phy2.70411 · Cited by 4
Sarcopenia as a complication of type 1 diabetes mellitus
Makarova, O. B., Lyapunova, A. I., Suplotova, L. A., & Alieva, O. O. (2025) · Perm Medical Journal · doi:10.17816/pmj4235-16 · Cited by 1
Hua, L., Wang, Y., Yuan, X., Wang, R., Li, X., Fan, Y., Hou, Z., Yang, L., Liu, T., & Sun, Q. (2026) · Journal of Ethnopharmacology · doi:10.1016/j.jep.2026.121444 · Cited by 1
Zhang, Y.-D., Zhao, X.-X., & Liu, X. (2026) · Frontiers in Physiology · doi:10.3389/fphys.2026.1773632 · Cited by 1
Correlation of sarcopenia and depression: common risk factors and pathogenetic mechanisms
Мамутовна, М. Э., Yafarova, A. A., Sheptulina, A. F., Yakovleva, P. O., & Drapkina, O. M. (2023) · Russian Journal of Preventive Medicine · doi:10.17116/profmed20232611157 · Cited by 1
Wang, P., Pang, Q., & Zhang, A. (2025) · Calcified Tissue International · doi:10.1007/s00223-025-01372-y · Cited by 1
Berković, M. C., Cigrovski, V., & Ružić, L. (2025) · World Journal of Methodology · doi:10.5662/wjm.v15.i4.105462 · Cited by 4
Khwaja, R., Dessouky, R., Heffler, M. A., Xi, Y., Neeland, I. J., & Chhabra, A. B. (2019) · European Journal of Radiology · doi:10.1016/j.ejrad.2019.01.001 · Cited by 1
Application Prospects of Biomarkers in the Diagnosis and Screening of Sarcopenia
李, 洪. (2023) · Advances in Clinical Medicine · doi:10.12677/acm.2023.1381818
Obesity, Myokines, and Metabolic Health
Malandrino, N., & Ahima, R. S. (2023) · Springer eBooks · doi:10.1007/978-3-319-12125-3_56-1
Muskulatur: „peripheres mechanisch- und Signalstoff-gestütztes Zentrum der Gesundheit“
Laube, W. (2023) · Springer eBooks · doi:10.1007/978-3-662-67753-7_8
Micah Isaac Anand, W. (2023) · International Journal of Science and Research (IJSR) · doi:10.21275/sr23516191456
Chronic Low-Grade Inflammation and Sarcopenia
王, 锐. (2024) · Advances in Clinical Medicine · doi:10.12677/acm.2024.1461784
Plasma irisin levels in newly diagnosed leprosy patients: a case-control study
Ali, M., Taieb, M. A. E., Younis, A., Zaki, E. N., Ahmed, N. M., Ibrahim, A. K., & Abdellatif, M. A. A. (2025) · Archives of Dermatological Research · doi:10.1007/s00403-025-03869-w
Research Progress on the Relationship between Dynapenic Obesity and Type 2 Diabetes
Li, Y., & Zhou, B. (2025) · Journal of Biosciences and Medicines · doi:10.4236/jbm.2025.132020
Biomarqueurs sanguins de l’atrophie musculaire : une opportunité de diagnostic
Aniort, J., Delabrise, C., Heng, A.-É., & Taillandier, D. (2025) · Cahiers de Nutrition et de Diététique · doi:10.1016/j.cnd.2025.02.003
Kim, C.-Y., & Byun, Y.-H. (2025) · Exercise Science · doi:10.15857/ksep.2025.00108
Du, X., Chenhang, Y., Huang, R., Zeng, Y., & Mao, S. (2025) · Journal of Science in Sport and Exercise · doi:10.1007/s42978-026-00375-x
Association of circulating muscle-derived myokines irisin and myostatin with COVID-19 severity
Daroszewski, C., Grzegrzółka, J., Kosacka, M., & Brzecka, A. (2026) · Frontiers in Endocrinology · doi:10.3389/fendo.2025.1668035
Myostatin and irisin in predicting the outcomes of patients with systemic inflammation
Pšenička, O., Kršáková, Z., & Křížová, J. (2025) · Vnitřní lékařství · doi:10.36290/vnl.2025.063
Suriano, C., Terrevoli, O. D., Staffieri, F., Lacitignola, L., Crovace, A., Pellicani, L., Taurino, M., Colucci, S. C., Grano, M., Crovace, A. M., et al. (2026) · JBMR Plus · doi:10.1093/jbmrpl/ziag057
Pšenička, O., Brutvan, T., Vítková, H., Kršáková, Z., Krátký, J., Škrha, J., & Křížová, J. (2026) · Research Square · doi:10.21203/rs.3.rs-8991519/v1
Novel biomarkers for sarcopenia: a narrative review
Chen, X., Wu, F., Shi, S., Xia, L., Wang, Y., Wei, Y., Wang, J., Li, J., Zhu, M., Zhang, X. W., et al. (2026) · Journal of Orthopaedic Surgery and Research · doi:10.1186/s13018-026-06880-7
Taj, J., Zafar, R., Ekouo, J., Junaid, A., Makeda, D., Latif, K., & Yokolo, H. (2026) · Health Science Reports · doi:10.1002/hsr2.72659
Sarcopenic obesity in adolescents: prevalence, diagnostic criteria and predisposing factors
Lebedeva, L. S., Евдокимова, Н. В., & Новикова, В. П. (2026) · Perm Medical Journal · doi:10.17816/pmj43368-77
Frigerio, F., & Donini, L. M. (2026) · Endocrinology · doi:10.1007/978-3-030-71067-5_23-1
Zheng, Z., Han, Y., Tang, X., Zhu, L., He, Y., Wang, F., Zhan, Y., & Cheng, W. (2026) · Clinical Rheumatology · doi:10.1007/s10067-026-08339-w
Akashi, N., Kondo, K., Kadota, A., Torii, S., Kadowaki, S., Miyazawa, I., Sekine, C., Iemitsu, M., HISAMATSU, T., 原田, 晃., et al. (2026) · Osteoporosis and Sarcopenia · doi:10.1016/j.afos.2026.10.003
Aljawini, N., Habib, S. S., & Al-Regaiey, K. (2026) · Nutrients · doi:10.3390/nu18213531
Metadata
- Authors
- Chang, J. S., Kim, T. H., Nguyen, T. T., Park, K., Kim, N., & Kong, I. D.
- Affiliations
- Yonsei University (KR)
- Department of Physiology Tan Tao University College of Medicine Long An Vietnam
- Keimyung University (KR)
- Corresponding author
- Kong, In Deok
- Venue
- Geriatrics & Gerontology International
- Publisher
- Wiley
- Published
- 2017-04-10
- Volume
- 17
- Issue
- 11
- Pages
- 2266-2273
- ISSN
- 1444-1586 (ISSN-L)
- 1447-0594
- OpenAlex
- W2606294901
- Cited by
- 166
- References
- 33
- Citations by year
- 2026: 16 · 2025: 30 · 2024: 15 · 2023: 27 · 2022: 29 · 2021: 15 · 2020: 14 · 2019: 9 · 2018: 7 · 2017: 4
- FWCI
- 6.88
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Geriatrics and gerontology international/Geriatrics & gerontology international (publishedVersion, cc-by-nc-nd)
- PubMed (publishedVersion)
- KUMeL Repository (Keimyung University) (submittedVersion, cc-by-nc-nd)
- Funders
- Research Grants, Yonsei University Wonju College of Medicine (YUWCM-2013-24)
- Topics
- Health Sciences › Medicine › Physiology (medical) › Nutrition and Health in Aging
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Muscle Physiology and Disorders
- Health Sciences › Medicine › Physiology (medical) › Body Composition Measurement Techniques
- Keywords
- irisin, sarcopenia, myokines, serum biomarkers, muscle weakness, muscle atrophy, Asian Working Group for Sarcopenia criteria, community-dwelling older adults, age-related muscle loss, predictive value
- MeSH terms
- Cross-Sectional Studies, Female, Fibronectins, Humans, Male, Predictive Value of Tests, Biomarkers, Sarcopenia
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
