The DOI matches its Crossref record; 53 of the 54 references it cites were found in a registry or an index.
Circulating factors associated with sarcopenia during ageing and after intensive lifestyle intervention
Open accessAbstract
Background: Ageing, chronic diseases, prolonged inactivity, and inadequate nutrition pose a severe threat to skeletal muscle health and function. To date, experimental evidence suggests that ageing‐related subclinical inflammation could be an important causative factor in sarcopenia. Although inflammatory signalling has been implicated in the pathogenesis of experimental animal models of sarcopenia, few studies have surveyed the clinical association between circulating factors and muscle mass in patients before and after lifestyle interventions. In this study, we evaluated whether proinflammatory cytokines are associated with the onset of sarcopenia, which circulating factors are associated with the severity of sarcopenia, and how these factors change after lifestyle interventions in sarcopenic elderly persons. Methods: A total of 56 elderly subjects (age ≥ 60 years) with sarcopenia and 56 elderly non‐sarcopenic subjects, who met entry criteria and had given informed consent, were selected from the Peking Union Medical College Hospital multicentre prospective longitudinal sarcopenia study for testing relevant circulating factors. Thirty‐two elderly subjects from the sarcopenic cohort completed a 12 week intensive lifestyle intervention programme with whey supplements (30 g/day) and a personalized resistance training regimen. The levels of proinflammatory cytokines and metabolic hormones, pre‐intensive and post‐intensive lifestyle interventions, were measured. Results: The sarcopenic group was significantly older (72.05 ± 6.54 years; P < 0.001), more likely to be inactive and female (57.1% of all sarcopenic patients), and had a higher prevalence of type 2 diabetes (16% higher risk). Compared with non‐sarcopenic subjects, serum interleukin (IL)‐6, IL‐18, tumour necrosis factor‐α (TNF‐α), TNF‐like weak inducer of apoptosis (TWEAK), and leptin were significantly higher, while insulin growth factor 1, insulin, and adiponectin were significantly lower in sarcopenic patients (all P < 0.05). Logistic regression analyses revealed that high levels of TNF‐α (>11.15 pg/mL) and TWEAK (>1276.48 pg/mL) were associated with a 7.6‐fold and 14.3‐fold increased risk of sarcopenia, respectively. After adjustment for confounding variables, high levels of TWEAK were still associated with a 13.4‐fold increased risk of sarcopenia. Intensive lifestyle interventions led to significant improvements in sarcopenic patients' muscle mass and serum profiles of TWEAK, TNF‐α, IL‐18, insulin, and adiponectin (all P < 0.05). Conclusions: High levels of the inflammatory cytokines TWEAK and TNF‐α are associated with an increased risk of sarcopenia, while the metabolic hormones insulin growth factor 1, insulin, and adiponectin are associated with a decreased risk of sarcopenia in our Chinese patient cohort. Intensive lifestyle interventions could significantly improve muscle mass, reduce inflammation, and restore metabolic hormone levels in sarcopenic patients. This trial was registered at clinicaltrials.gov as NCT02873676.
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
“Under pathological conditions, TWEAK also becomes overexpressed and activates the NF‐κB pathway via the FGF‐inducible 14 receptors, leading to increased expression of MuRF1 and activation of the ubiquitin‐proteasome (UPS) pathway as well.[ 69 ]”
From Pathogenesis of sarcopenia and the relationship with fat mass: descriptive review (2022) · cites this paper as [69]
In the citing paper
“Cytokines such as TNF‐α, TNF‐like weak promoter of apoptosis (TWEAK), IL‐18, and IL‐6, are thought to induce muscle atrophy during sarcopenia.[ 69 ]”
From Pathogenesis of sarcopenia and the relationship with fat mass: descriptive review (2022) · cites this paper as [69]
In the citing paper
“Intensive lifestyle interventions lasting 12 weeks (three times a week), including whey supplementation and resistance exercise, can significantly lower the leptin level, restore metabolic hormone levels, and ameliorate muscle mass in sarcopenic patients [85].”
From Exerkines and Sarcopenia: Unveiling the Mechanism Behind Exercise-Induced Mitochondrial Homeostasis (2025) · cites this paper as [85]
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
Folstein, M. F., Folstein, S. E., & McHugh, P. R. (1975) · Journal of Psychiatric Research · doi:10.1016/0022-3956(75)90026-6 · Cited by 88,282
Sarcopenia: European consensus on definition and diagnosis
Cruz-Jentoft, A. J., Baeyens, J. P., Bauer, J. M., Boirie, Y., Cederholm, T., Landi, F., Martin, F. C., Michel, J.-P., Rolland, Y., Schneider, S. M., et al. (2010) · Age and Ageing · doi:10.1093/ageing/afq034 · Cited by 11,601
Guralnik, J. M., Simonsick, E. M., Ferrucci, L., Glynn, R. J., Berkman, L. F., Blazer, D. G., Scherr, P. A., & Wallace, R. B. (1994) · Journal of Gerontology · doi:10.1093/geronj/49.2.m85 · Cited by 9,792
Adipokines in inflammation and metabolic disease
Ouchi, N., Parker, J. L., Lugus, J. J., & Walsh, K. (2011) · Nature Reviews Immunology · doi:10.1038/nri2921 · Cited by 4,625
Yamauchi, T., Kamon, J., Minokoshi, Y., Ito, Y., Waki, H., Uchida, S., Yamashita, S., Noda, M., Kita, S., Ueki, K., et al. (2002) · Nature Medicine · doi:10.1038/nm788 · Cited by 4,238
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
Skeletal Muscle Cutpoints Associated with Elevated Physical Disability Risk in Older Men and Women
Janssen, I. (2004) · American Journal of Epidemiology · doi:10.1093/aje/kwh058 · Cited by 1,190
Endotoxin and cytokines induce expression of leptin, the ob gene product, in hamsters.
Grünfeld, C., Zhao, C., Fuller, J., Pollack, A., Moser, A. H., Friedman, J. M., & Kr, F. (1996) · Journal of Clinical Investigation · doi:10.1172/jci118653 · Cited by 871
Vitamin D Status Predicts Physical Performance and Its Decline in Older Persons
Wicherts, I. S., van Schoor, N. M., Boeke, A. J. P., Visser, M., Deeg, D. J. H., Smit, J., Knol, D. L., & Lips, P. (2007) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jc.2006-1525 · Cited by 606
Frisancho, A. R. (1984) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/40.4.808 · Cited by 571
Nuclear factor-kappa B signaling in skeletal muscle atrophy
Li, H., Malhotra, S., & Kumar, A. (2008) · Journal of Molecular Medicine · doi:10.1007/s00109-008-0373-8 · Cited by 464
Chronic low-grade inflammation and age-related sarcopenia
Beyer, I., Mets, T., & Bautmans, I. (2012) · Current Opinion in Clinical Nutrition and Metabolic Care · doi:10.1097/mco.0b013e32834dd297 · Cited by 400
Signaling pathways perturbing muscle mass.
Glass, D. J. (2010) · Current Opinion in Clinical Nutrition and Metabolic Care · doi:10.1097/mco.0b013e32833862df · Cited by 359
Ethical guidelines for publishing in the journal of cachexia, sarcopenia and muscle: update 2017
von Haehling, S., Morley, J. E., Coats, A. J. S., & Anker, S. D. (2017) · Journal of Cachexia Sarcopenia and Muscle · doi:10.1002/jcsm.12261 · Cited by 351
Kim, J.-K., Choi, S. R., Choi, M.-J., Kim, S. G., Lee, Y. K., Noh, J., Kim, H. J., & Song, Y. R. (2013) · Clinical Nutrition · doi:10.1016/j.clnu.2013.04.002 · Cited by 292
International Physical Activity Questionnaire: Reliability and validity in a Spanish population
Román‐Viñas, B., Serra‐Majem, L., Hagströmer, M., Ribas‐Barba, L., Sjöstróm, M., & Segura‐Cardona, R. (2010) · European Journal of Sport Science · doi:10.1080/17461390903426667 · Cited by 260
C-reactive protein and cardiovascular disease: new insights from an old molecule
Hirschfield, G. M., & Pepys, M. B. (2003) · QJM · doi:10.1093/qjmed/hcg134 · Cited by 256
The TWEAK–Fn14 system is a critical regulator of denervation-induced skeletal muscle atrophy in mice
Mittal, A., Bhatnagar, S., Kumar, A., Lach-Trifilieff, E., Wauters, S., Li, H., Makonchuk, D. Y., Glass, D. J., & Kumar, A. (2010) · Journal of Cell Biology · doi:10.1083/jcb.200909117 · Cited by 250
Sporadic inclusion body myositis—diagnosis, pathogenesis and therapeutic strategies
Dalakas, M. C. (2006) · Nature Clinical Practice Neurology · doi:10.1038/ncpneuro0261 · Cited by 229
Mattsby‐Baltzer, I., Roșeanu, A., Motaş, C., Elverfors, J., Engberg, I., & Hanson, L. Å. (1996) · Pediatric Research · doi:10.1203/00006450-199608000-00011 · Cited by 189
Serum markers of inflammation and oxidative stress in sarcopenia
Can, B., Kara, O., Kizilarslanoglu, M. C., Arik, G., Aycicek, G. S., Sumer, F., Civelek, R., Demirtas, C., & Ulger, Z. (2017) · Aging Clinical and Experimental Research · doi:10.1007/s40520-016-0626-2 · Cited by 176
Cytokine Signaling in Skeletal Muscle Wasting
Zhou, J., Liu, B., Liang, C., Li, Y., & Song, Y.-H. (2016) · Trends in Endocrinology & Metabolism · doi:10.1016/j.tem.2016.03.002 · Cited by 172
Adiponectin is expressed by skeletal muscle fibers and influences muscle phenotype and function
Krause, M. P., Liu, Y., Vu, V., Chan, L., Xu, A., Riddell, M. C., Sweeney, G., & Hawke, T. J. (2008) · American Journal of Physiology-Cell Physiology · doi:10.1152/ajpcell.00030.2008 · Cited by 168
Alemán-Mateo, H., Esparza‐Romero, J., Ramirez, F. A., Astiazarán‐García, H., & Payette, H. (2011) · Age and Ageing · doi:10.1093/ageing/afr040 · Cited by 163
Hamrick, M. W., Herberg, S., Arounleut, P., He, H.-Z., Shiver, A. L., Qi, R.-Q., Zhou, L., Isales, C. M., & Mi, Q. (2010) · Biochemical and Biophysical Research Communications · doi:10.1016/j.bbrc.2010.08.079 · Cited by 157
Inflammatory Markers and Gait Speed Decline in Older Adults
Verghese, J., Holtzer, R., Oh‐Park, M., Derby, C. A., Lipton, R. B., & Wang, C. (2011) · The Journals of Gerontology Series A · doi:10.1093/gerona/glr099 · Cited by 155
Berendoncks, A. M. V., Garnier, A., Beckers, P. J., Hoymans, V. Y., Possemiers, N. M., Fortin, D., Martinet, W., Hoof, V. O. V., Vrints, C. J., Ventura‐Clapier, R., et al. (2010) · Circulation Heart Failure · doi:10.1161/circheartfailure.109.885525 · Cited by 154
Regulation of muscle atrophy in aging and disease
Vinciguerra, M., Musaro, A., & Rosenthal, N. (2010) · Advances in experimental medicine and biology · doi:10.1007/978-1-4419-7002-2_15 · Cited by 149
Modulation of GH/IGF-1 axis: Potential strategies to counteract sarcopenia in older adults
Giovannini, S., Marzetti, E., Borst, S. E., & Leeuwenburgh, C. (2008) · Mechanisms of Ageing and Development · doi:10.1016/j.mad.2008.08.001 · Cited by 136
Luo, J., Sobkiw, C. L., Hirshman, M. F., Logsdon, M. N., Li, T. Q., Goodyear, L. J., & Cantley, L. C. (2006) · Cell Metabolism · doi:10.1016/j.cmet.2006.04.003 · Cited by 123
Kyrdalen, I. L., Moen, K., Røysland, A. S., & Helbostad, J. L. (2013) · Physiotherapy Research International · doi:10.1002/pri.1571 · Cited by 120
Zhou, Q., Du, J., Hu, Z., Walsh, K. X., & Wang, X. H. (2007) · Endocrinology · doi:10.1210/en.2007-0183 · Cited by 105
Ticinesi, A., Meschi, T., Lauretani, F., Felis, G. E., Franchi, F., Pedrolli, C., Barichella, M., Benati, G., Nuzzo, S. D., Ceda, G. P., et al. (2016) · Nutrients · doi:10.3390/nu8040186 · Cited by 104
Gunnerud, U., Östman, E. M., & Björck, I. (2013) · European Journal of Clinical Nutrition · doi:10.1038/ejcn.2013.88 · Cited by 98
Bucci, L., Yani, S. L., Fabbri, C., Bijlsma, A. Y., Maier, A. B., Meskers, C. G. M., Narici, M. V., Jones, D. A., McPhee, J. S., Seppet, E. K., et al. (2013) · Biogerontology · doi:10.1007/s10522-013-9428-5 · Cited by 93
Inoue, A., Cheng, X. W., Huang, Z., Hu, L., Kikuchi, R., Jiang, H., Piao, L., Sasaki, T., Itakura, K., Wu, H., et al. (2017) · Journal of Cachexia Sarcopenia and Muscle · doi:10.1002/jcsm.12166 · Cited by 89
Description of a local cardiac adiponectin system and its deregulation in dilated cardiomyopathy
Skurk, C., Wittchen, F., Suckau, L., Witt, H., Noutsias, M., Fechner, H., Schultheiss, H.-P., & Poller, W. C. (2008) · European Heart Journal · doi:10.1093/eurheartj/ehn136 · Cited by 86
TWEAK and cIAP1 Regulate Myoblast Fusion Through the Noncanonical NF-κB Signaling Pathway
Enwere, E. K., Holbrook, J., Mrad, R. L., Vineham, J., Timusk, K., Sivaraj, B., Isaac, M. B., Uehling, D., Al‐awar, R., LaCasse, E. C., et al. (2012) · Science Signaling · doi:10.1126/scisignal.2003086 · Cited by 85
Shahar, S., Norshafarina, Badrasawi, M., Noor, N., Manaf, Z. A., Yassin, M. Z., & Joseph, L. (2013) · Clinical Interventions in Aging · doi:10.2147/cia.s46826 · Cited by 85
Elevated Levels of IL-18 in Plasma and Skeletal Muscle in Chronic Obstructive Pulmonary Disease
Petersen, A. M. W., Penkowa, M., Iversen, M., Frydelund-Larsen, L., Andersen, J. L., Mortensen, J., Lange, P., & Pedersen, B. K. (2007) · Lung · doi:10.1007/s00408-007-9000-7 · Cited by 83
Yamaguchi, M., Yoshida, K., & Uchida, M. (2009) · Biological and Pharmaceutical Bulletin · doi:10.1248/bpb.32.366 · Cited by 81
Role of the Cytokine-like Hormone Leptin in Muscle-bone Crosstalk with Aging
Hamrick, M. W. (2017) · Journal of Bone Metabolism · doi:10.11005/jbm.2017.24.1.1 · Cited by 77
Bautmans, I., Onyema, O. O., Puyvelde, K. V., Pleck, S., & Mets, T. F. (2010) · The journal of nutrition health & aging · doi:10.1007/s12603-010-0317-1 · Cited by 67
Haren, M. T., Malmstrom, T. K., Miller, D. K., Patrick, P., Perry, H. M., Herning, M. M., Banks, W. A., & Morley, J. E. (2009) · The Journals of Gerontology Series A · doi:10.1093/gerona/glp148 · Cited by 65
Globular adiponectin reverses osteo-sarcopenia and altered body composition in ovariectomized rats
China, S. P., Pal, S., Chattopadhyay, S., Porwal, K., Kushwaha, S., Bhattacharyya, S., Mittal, M., Gurjar, A. A., Barbhuyan, T. K., Singh, A. K., et al. (2017) · Bone · doi:10.1016/j.bone.2017.08.005 · Cited by 53
Huang, C. X., Tomata, Y., Kakizaki, M., Sugawara, Y., Hozawa, A., Momma, H., Tsuji, I., & Nagatomi, R. (2015) · Nutrition Metabolism and Cardiovascular Diseases · doi:10.1016/j.numecd.2015.03.010 · Cited by 45
Manoy, P., Anomasiri, W., Yuktanandana, P., Tanavalee, A., Ngarmukos, S., Tanpowpong, T., & Honsawek, S. (2017) · Biomarkers · doi:10.1080/1354750x.2017.1315615 · Cited by 43
Yamada, C., Moriyama, K., & Takahashi, E. (2012) · Journal of Diabetes Investigation · doi:10.1111/j.2040-1124.2012.00194.x · Cited by 41
The TWEAK–Fn14 dyad is involved in age-associated pathological changes in skeletal muscle
Tajrishi, M. M., Sato, S., Shin, J. S., Zheng, T. S., Burkly, L. C., & Kumar, A. (2014) · Biochemical and Biophysical Research Communications · doi:10.1016/j.bbrc.2014.03.084 · Cited by 35
TWEAK in Inclusion-Body Myositis Muscle
Roberta Morosetti, A., Gliubizzi, C., Sancricca, C., Broccolini, A., Gidaro, T., Lucchini, M., & Massimiliano Mirabella, A. (2012) · American Journal Of Pathology · doi:10.1016/j.ajpath.2011.12.027 · Cited by 32
The adipokine leptin mediates muscle- and liver-derived IGF-1 in aged mice
Hamrick, M. W., Dukes, A., Arounleut, P., Davis, C. L., Periyasamy‐Thandavan, S., Mork, S., Herberg, S., Johnson, M. H., Isales, C. M., Hill, W., et al. (2015) · Experimental Gerontology · doi:10.1016/j.exger.2015.07.014 · Cited by 30
Insights into Muscle Degeneration from Heritable Inclusion Body Myopathies
Krause, S. (2015) · Frontiers in Aging Neuroscience · doi:10.3389/fnagi.2015.00013 · Cited by 13
Cytokine Profiling of Serum Allows Monitoring of Disease Progression in Inclusion Body Myositis
Badrising, U. A., Tsonaka, R., Hiller, M., Niks, E. H., Evangelista, T., Lochmüller, H., Verschuuren, J. J. G. M., Aartsma-Rus, A. M., & Spitali, P. (2017) · Journal of Neuromuscular Diseases · doi:10.3233/jnd-170234 · Cited by 10
Flagged first, then by citations
1 of the 54 references couldn’t be matched to a known paper.
Cited by
Sorted by citations
Tuttle, C. S. L., Thang, L. A. N., & Maier, A. B. (2020) · Ageing Research Reviews · doi:10.1016/j.arr.2020.101185 · Cited by 664
Pathogenesis of sarcopenia and the relationship with fat mass: descriptive review
Li, C., Yu, K., Shyh‐Chang, N., Jiang, Z., Liu, T., Ma, S., Luo, L., Guang, L., Liang, K., Ma, W., et al. (2022) · Journal of Cachexia, Sarcopenia and Muscle · doi:10.1002/jcsm.12901 · Cited by 626
Self-citationBao, H., Cao, J., Chen, M., Min, C., Chen, W., Chen, X., Chen, Y., Chen, Y., Chen, Y., Chen, Z., et al. (2023) · Science China Life Sciences · doi:10.1007/s11427-023-2305-0 · Cited by 402
Self-citationInflammation and sarcopenia: A focus on circulating inflammatory cytokines
Pan, L., Xie, W., Fu, X., Lu, W., Jin, H., Lai, J., Zhang, A., Yu, Y., Li, Y., & Xiao, W. (2021) · Experimental Gerontology · doi:10.1016/j.exger.2021.111544 · Cited by 321
Inflammaging: Implications in Sarcopenia
Antuña, E., Cachán-Vega, C., Bermejo-Millo, J. C., Potes, Y., Caballero, B., Vega‐Naredo, I., Coto‐Montes, A. M., & García-González, C. (2022) · International Journal of Molecular Sciences · doi:10.3390/ijms232315039 · Cited by 234
Metadata
- Authors
- Li, C., Yu, K., Shyh‐Chang, N., Li, G., Jiang, L., Yu, S., Xu, L., Liu, R., Guo, Z., Xie, H., Li, R., Ying, J., Li, K., & Li, D.
- Affiliations
- Chinese Academy of Medical Sciences & Peking Union Medical College (CN)
- Chinese Academy of Sciences (CN)
- Department of General Surgery and Clinical Nutrition TianJin Union Medical Center Hongqiao District Tianjin China
- Department of Central Laboratory Peking Union Medical College Hospital, Chinese Academy of Medical Sciences Dongcheng District Beijing China
- Department of Clinical Laboratory Peking Union Medical College Hospital, Chinese Academy of Medical Sciences Dongcheng District Beijing China
- Department of Health Care Peking Union Medical College Hospital, Chinese Academy of Medical Sciences Dongcheng District Beijing China
- Department of Clinical Nutrition and Department of Health Medicine Peking Union Medical College Hospital, Chinese Academy of Medical Sciences Dongcheng District Beijing China
- Corresponding author
- Yu, Kang
- Shyh‐Chang, Ng
- Venue
- Journal of Cachexia, Sarcopenia and Muscle
- Publisher
- Wiley
- Published
- 2019-04-10
- Volume
- 10
- Issue
- 3
- Pages
- 586-600
- ISSN
- 2190-5991 (ISSN-L)
- 2190-6009
- PMC
- PMC6596393
- OpenAlex
- W2938744410
- Cited by
- 280
- References
- 54
- Citations by year
- 2026: 26 · 2025: 46 · 2024: 54 · 2023: 71 · 2022: 41 · 2021: 25 · 2020: 17
- FWCI
- 14.23
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- Journal of Cachexia Sarcopenia and Muscle (publishedVersion, cc-by-nc-nd)
- PubMed Central (publishedVersion, cc-by-nc-nd)
- PubMed (publishedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Funders
- Chinese Academy of Sciences (XDA16020301, KJZD-SW-L04)
- 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 › Nursing › Nutrition and Dietetics › Muscle metabolism and nutrition
- Keywords
- sarcopenia, aging, inflammatory cytokines, TWEAK, TNF-α, interleukin-6, IL-18, leptin, insulin-like growth factor I, adiponectin, whey protein supplementation, resistance training, lifestyle intervention, older adults, muscle mass, subclinical inflammation, type 2 diabetes, metabolic hormones, sarcopenia risk
- MeSH terms
- Healthy Lifestyle, Cytokine TWEAK, Aged, Aging, Body Composition, China, Cross-Sectional Studies, Female, Humans, Inflammation, Longitudinal Studies, Male, Middle Aged, Prospective Studies, Severity of Illness Index, Tumor Necrosis Factor-alpha, Treatment Outcome, Muscle, Skeletal, Inflammation Mediators, Resistance Training, 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
