Feasibility of Single Channel Oximetry for Mass Screening of Obstructive Sleep Apnea
Open accessAbstract
BACKGROUND: The growing awareness for the high prevalence of obstructive sleep apnea (OSA) coupled with the dramatic proportion of undiagnosed individuals motivates the elaboration of a simple but accurate screening test. This study assesses, for the first time, the performance of oximetry combined with demographic information as a screening tool for identifying OSA in a representative (i.e. non-referred) population sample. METHODS: A polysomnography (PSG) clinical database of 887 individuals from a representative population sample of São Paulo's city (Brazil) was used. Using features derived from the oxygen saturation signal during sleep periods and demographic information, a logistic regression model (termed OxyDOSA) was trained to distinguish between non-OSA and OSA individuals (mild, moderate, and severe). The OxyDOSA model performance was assessed against the PSG-based diagnosis of OSA (AASM 2017) and compared to the NoSAS and STOP-BANG questionnaires. FINDINGS: The OxyDOSA model had mean AUROC = 0.94 ± 0.02, Se = 0.87 ± 0.04 and Sp = 0.85 ± 0.03. In particular, it did not miss any of the 75 severe OSA individuals. In comparison, the NoSAS questionnaire had AUROC = 0.83 ± 0.03, and missed 23/75 severe OSA individuals. The STOP-BANG had AUROC = 0.77 ± 0.04 and missed 14/75 severe OSA individuals. INTERPRETATION: We provide strong evidence on a representative population sample that oximetry biomarkers combined with few demographic information, the OxyDOSA model, is an effective screening tool for OSA. Our results suggest that sleep questionnaires should be used with caution for OSA screening as they fail to identify many moderate and even some severe cases. The OxyDOSA model will need to be further validated on data recorded using overnight portable oximetry.
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 model has been developed to identify OSA using data that could be obtained from a wearable user (pulse oximetry biomarkers and demographic information).
“a model has been developed to identify OSA using data, which could be obtained from a wearable user (pulse oximetry biomarkers and demographic information)”
From Wearable Photoplethysmography for Cardiovascular Monitoring (2022) · cites this paper as [206]
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
Regression shrinkage and selection via the lasso
Tibshirani, R. (1996) · Journal of the Royal Statistical Society Series B: Statistical Methodology · doi:10.1111/j.2517-6161.1996.tb02080.x · Cited by 51,482 · see citing works
Berry, R. B., Budhiraja, R., Gottlieb, D. J., Gozal, D., Iber, C., Kapur, V. K., Marcus, C. L., Mehra, R., Parthasarathy, S., Quan, S. F., et al. (2012) · Journal of Clinical Sleep Medicine · doi:10.5664/jcsm.2172 · Cited by 5,302 · see citing works
Prevalence of sleep-disordered breathing in the general population: the HypnoLaus study
Heinzer, R., Vat, S., Marques-Vidal, P., Marti-Soler, H., Andries, D., Tobback, N., Mooser, V, Preisig, M., Malhotra, A., Waeber, G., et al. (2015) · The Lancet Respiratory Medicine · doi:10.1016/s2213-2600(15)00043-0 · Cited by 2,481 · see citing works
Young, T., Evans, L., Finn, L., & Palta, M. (1997) · Sleep · doi:10.1093/sleep/20.9.705 · Cited by 1,765 · see citing works
AASM Scoring Manual Updates for 2017 (Version 2.4)
Berry, R. B., Brooks, R., Gamaldo, C. E., Harding, S. M., Lloyd, R. M., Quan, S. F., Troester, M. M., & Vaughn, B. V. (2017) · Journal of Clinical Sleep Medicine · doi:10.5664/jcsm.6576 · Cited by 1,605 · see citing works
Obstructive Sleep Apnea Syndrome in the Sao Paulo Epidemiologic Sleep Study
Tufik, S., Santos-Silva, R., Taddei, J. A., & Bittencourt, L. R. A. (2010) · Sleep Medicine · doi:10.1016/j.sleep.2009.10.005 · Cited by 1,069 · cited 5× · see citing works
“The original clinical trial of the EPISONO study [1,29] was supported by theAssociação Fundo de Incentivo a Pesquisa (AFIP), Coordenação de Aperfeicoamento de Pessoal de Nível Superior (CAPES) and São Paulo Research Foundation (FAPESP).”
InfluentialSelf-citationObstructive sleep apnoea syndrome – an oxidative stress disorder
Lavie, L. (2003) · Sleep Medicine Reviews · doi:10.1053/smrv.2002.0261 · Cited by 993 · cited 1× · see citing works
“In addition, it is possible that the repetitive nocturnal hypoxemia in OSA causes oxidative stress contributing to the pathogenesis of cardiovascular morbidity [17,18].”
High STOP-Bang score indicates a high probability of obstructive sleep apnoea
Chung, F., Subramanyam, R., Liao, P., Sasaki, E., Shapiro, C., & Sun, Y. (2012) · British Journal of Anaesthesia · doi:10.1093/bja/aes022 · Cited by 988 · see citing works
Dyugovskaya, L., Lavie, P., & Lavie, L. (2002) · American Journal of Respiratory and Critical Care Medicine · doi:10.1164/ajrccm.165.7.2104126 · Cited by 742 · see citing works
Obstructive Sleep Apnea and Diabetes
Reutrakul, S., & Mokhlesi, B. (2017) · Chest · doi:10.1016/j.chest.2017.05.009 · Cited by 667 · see citing works
Sleep Apnea and Cardiovascular Disease: Lessons From Recent Trials and Need for Team Science
Drager, L. F., McEvoy, R. D., Barbe, F., Lorenzi-Filho, G., & Redline, S. (2017) · Circulation · doi:10.1161/circulationaha.117.029400 · Cited by 465 · see citing works
Finkel, K. J., Searleman, A. C., Tymkew, H., Tanaka, C. Y., Saager, L., Safer-Zadeh, E., Bottros, M. M., Selvidge, J. A., Jacobsohn, E., Pulley, D. D., et al. (2009) · Sleep Medicine · doi:10.1016/j.sleep.2008.08.007 · Cited by 459 · see citing works
The Medical Cost of Undiagnosed Sleep Apnea
Kapur, V., Blough, D. K., Sandblom, R. E., Hert, R., de Maine, J. B., Sullivan, S. D., & Psaty, B. M. (1999) · Sleep · doi:10.1093/sleep/22.6.749 · Cited by 384 · see citing works
The NoSAS score for screening of sleep-disordered breathing: a derivation and validation study
Marti-Soler, H., Hirotsu, C., Marques-Vidal, P., Vollenweider, P., Waeber, G., Preisig, M., Tafti, M., Tufik, S. B., Bittencourt, L., Tufik, S., et al. (2016) · The Lancet Respiratory Medicine · doi:10.1016/s2213-2600(16)30075-3 · Cited by 317 · see citing works
Self-citationClinical consequences and economic costs of untreated obstructive sleep apnea syndrome
Knauert, M. P., Naik, S., Gillespie, M. B., & Kryger, M. H. (2015) · World Journal of Otorhinolaryngology - Head and Neck Surgery · doi:10.1016/j.wjorl.2015.08.001 · Cited by 297 · see citing works
Chung, F., Liao, P., Elsaid, H., Islam, S., Shapiro, C. M., & Sun, Y. (2012) · Anesthesia & Analgesia · doi:10.1213/ane.0b013e318248f4f5 · Cited by 243 · see citing works
Craig, S. E., Kohler, M., Nicoll, D., Bratton, D. J., Nunn, A., Davies, R., & Stradling, J. (2012) · Thorax · doi:10.1136/thoraxjnl-2012-202178 · Cited by 228 · see citing works
A review of signals used in sleep analysis
Roebuck, A., Monasterio, V., Gederi, E., Osipov, M., Behar, J. A., Malhotra, A., Penzel, T., & Clifford, G. D. (2013) · Physiological Measurement · doi:10.1088/0967-3334/35/1/r1 · Cited by 226 · see citing works
Self-citationZonato, A. I., Bittencourt, L. R., Martinho, F. L., Júnior, J. F. S., Gregório, L. C., & Tufik, S. (2003) · The Laryngoscope · doi:10.1097/00005537-200306000-00011 · Cited by 177 · see citing works
Self-citationTufik, S., Andersen, M. L., Bittencourt, L., & de Mello, M. T. (2009) · Anais da Academia Brasileira de Ciências · doi:10.1590/s0001-37652009000300016 · Cited by 171 · see citing works
Self-citationChiner, E., Signes‐Costa, J., Arriero, J. M., Marco, J., Fuentes, I., & Sergado, A. (1999) · Thorax · doi:10.1136/thx.54.11.968 · Cited by 157 · see citing works
Sao Paulo Epidemiologic Sleep Study: Rationale, design, sampling, and procedures
Santos‐Silva, R., Tufik, S., Conway, S. G., Taddei, J. A. D. A. C., & Bittencourt, L. (2009) · Sleep Medicine · doi:10.1016/j.sleep.2008.11.001 · Cited by 150 · see citing works
Self-citationA review of current sleep screening applications for smartphones
Behar, J. A., Roebuck, A., Domingos, J. S., Gederi, E., & Clifford, G. D. (2013) · Physiological Measurement · doi:10.1088/0967-3334/34/7/r29 · Cited by 130 · see citing works
Self-citationNew technology to assess sleep apnea: wearables, smartphones, and accessories
Penzel, T., Schöbel, C., & Fietze, I. (2018) · F1000Research · doi:10.12688/f1000research.13010.1 · Cited by 102 · see citing works
Obstructive Apnea Hypopnea Index Estimation by Analysis of Nocturnal Snoring Signals in Adults
Ben-Israel, N. I., Tarasiuk, A., & Zigel, Y. (2012) · SLEEP · doi:10.5665/sleep.2092 · Cited by 99 · see citing works
An Algorithm to Stratify Sleep Apnea Risk in a Sleep Disorders Clinic Population
Gurubhagavatula, I., Maislin, G., & Pack, A. I. (2001) · American Journal of Respiratory and Critical Care Medicine · doi:10.1164/ajrccm.164.10.2103039 · Cited by 84 · see citing works
Hirotsu, C., Haba‐Rubio, J., Togeiro, S. M., Marques-Vidal, P. M., Drager, L. F., Vollenweider, P., Waeber, G., Bittencourt, L., Tufik, S. B., & Heinzer, R. C. (2018) · European Respiratory Journal · doi:10.1183/13993003.01150-2018 · Cited by 82 · see citing works
Self-citationUddin, M. B., Chow, C. M., & Su, S. W. (2018) · Physiological Measurement · doi:10.1088/1361-6579/aaafb8 · Cited by 76 · see citing works
(2011) · CRC Press eBooks · doi:10.3109/9781420020885 · Cited by 61 · see citing works
Real-Time Automatic Apneic Event Detection Using Nocturnal Pulse Oximetry
Jung, D. W., Hwang, S. H., Cho, J. G., Choi, B., Baek, H. J., Lee, Y. J., Jeong, D., & Park, K. S. (2017) · IEEE Transactions on Biomedical Engineering · doi:10.1109/tbme.2017.2715405 · Cited by 61 · see citing works
Undiagnosed Obstructive Sleep Apnea and Postoperative Outcomes: A Prospective Observational Study
Devaraj, U., Rajagopala, S., Kumar, A. M. V., Ramachandran, P., Devereaux, P. J., & D′Souza, G. (2017) · Respiration · doi:10.1159/000470914 · Cited by 51 · see citing works
Oximetry use in obstructive sleep apnea
del Campo, F., Crespo, A., Cerezo-Hernández, A., Gutiérrez‐Tobal, G. C., Hornero, R., & Álvarez, D. (2018) · Expert Review of Respiratory Medicine · doi:10.1080/17476348.2018.1495563 · Cited by 49 · see citing works
Automated frequency domain analysis of oxygen saturation as a screening tool for SAHS
Morillo, D., Gross, N., León, A., & Crespo, L. F. (2011) · Medical Engineering & Physics · doi:10.1016/j.medengphy.2011.10.015 · Cited by 19 · see citing works
Roebuck, A., & Clifford, G. D. (2015) · Frontiers in Bioengineering and Biotechnology · doi:10.3389/fbioe.2015.00114 · Cited by 15 · see citing works
Self-citation
Flagged first, then by citations
Research works printed but not linked: 1
- [11]Pack A. Sleep apnea: Pathogenesis, diagnosis and treatment 2016 CRC Press Pack A. Sleep apnea: Pathogenesis, diagnosis and treatment. CRC Press, 2016.
Cited by
Sorted by citations
Wearable Photoplethysmography for Cardiovascular Monitoring
Charlton, P. H., Kyriacou, P. A., Mant, J., Marozas, V., Chowienczyk, P., & Alastruey, J. (2022) · Proceedings of the IEEE · doi:10.1109/jproc.2022.3149785 · Cited by 250 · see citing works
The 2023 wearable photoplethysmography roadmap
Charlton, P. H., Allen, J., Bailón, R., Baker, S., Behar, J. A., Chen, F., Clifford, G. D., Clifton, D. A., Davies, H. J., Ding, C., et al. (2023) · Physiological Measurement · doi:10.1088/1361-6579/acead2 · Cited by 210 · see citing works
Self-citationLevy, J., Álvarez, D., Rosenberg, A. A., Alexandrovich, A., del Campo, F., & Behar, J. A. (2021) · npj Digital Medicine · doi:10.1038/s41746-020-00373-5 · Cited by 125 · see citing works
Self-citationWearable Photoplethysmography for Cardiovascular Monitoring.
Charlton, P. H., Kyriacou, P. A., Mant, J., Marozas, V., Chowienczyk, P., & Alastruey, J. (2022) · KTUePubl (Repository of Kaunas University of Technology) · doi:10.17863/cam.81148 · Cited by 113 · see citing works
Deep learning for obstructive sleep apnea diagnosis based on single channel oximetry
Levy, J., Álvarez, D., Campo, F. D., & Behar, J. A. (2023) · Nature Communications · doi:10.1038/s41467-023-40604-3 · Cited by 102 · see citing works
Self-citationApplication of artificial intelligence in the diagnosis of sleep apnea
Bazoukis, G., Bollepalli, S. C., Chung, C. T., Li, X., Tse, G., Bartley, B. L., Batool‐Anwar, S., Quan, S. F., & Armoundas, A. A. (2023) · Journal of Clinical Sleep Medicine · doi:10.5664/jcsm.10532 · Cited by 91 · see citing works
Kotzen, K., Charlton, P. H., Salabi, S., Amar, L., Landesberg, A., & Behar, J. A. (2022) · IEEE Journal of Biomedical and Health Informatics · doi:10.1109/jbhi.2022.3225363 · Cited by 80 · see citing works
Self-citationBlanchard, M., Gervès‐Pinquié, C., Feuilloy, M., Vaillant, M. L., Trzépizur, W., Meslier, N., Paris, A., Pigeanne, T., Racineux, J.-L., Balusson, F., et al. (2021) · Annals of the American Thoracic Society · doi:10.1513/annalsats.202009-1202oc · Cited by 53 · see citing works
Kirszenblat, R., & Edouard, P. (2021) · Journal of Medical Internet Research · doi:10.2196/27503 · Cited by 50 · see citing works
pyPPG: a Python toolbox for comprehensive photoplethysmography signal analysis
Goda, M. Á., Charlton, P. H., & Behar, J. A. (2024) · Physiological Measurement · doi:10.1088/1361-6579/ad33a2 · Cited by 52 · see citing works
Self-citationPinheiro, G. D. L., Cruz, A. F., Domingues, D. M., Genta, P. R., Drager, L. F., Strollo, P. J., & Lorenzi‐Filho, G. (2020) · Clinics · doi:10.6061/clinics/2020/e2414 · Cited by 34 · see citing works
Behar, J. A., Palmius, N., Zacharie, S., Chocron, A., Penzel, T., Bittencourt, L., & Tufik, S. (2020) · Physiological Measurement · doi:10.1088/1361-6579/ab8856 · Cited by 20 · see citing works
Self-citationDiabetes and cardiovascular diseases are associated with the worsening of intermittent hypoxaemia
Karhu, T., Myllymaa, S., Nikkonen, S., Mazzotti, D. R., Kulkas, A., Töyräs, J., & Leppänen, T. (2021) · Journal of Sleep Research · doi:10.1111/jsr.13441 · Cited by 16 · see citing works
Liang, Z. (2023) · Digital Health · doi:10.1177/20552076231211550 · Cited by 14 · see citing works
Pulse oximetry SpO 2 signal for automated identification of sleep apnea: a review and future trends
Sharma, M. D., Kumar, K., Kumar, P., Tan, R., & Acharya, U. R. (2022) · Physiological Measurement · doi:10.1088/1361-6579/ac98f0 · Cited by 14 · see citing works
Sobel, J., Levy, J., Almog, R., Benaim, A. R., Miller, A., Eytan, D., & Behar, J. A. (2023) · Scientific Reports · doi:10.1038/s41598-022-27342-0 · Cited by 13 · see citing works
Self-citationThe Predictive Role of Subcutaneous Adipose Tissue in the Pathogenesis of Obstructive Sleep Apnoea
Molnár, V., Lakner, Z., Molnár, A., Tárnoki, D. L., Tárnoki, Á. D., Kunos, L., & Tamás, L. T. (2022) · Life · doi:10.3390/life12101504 · Cited by 13 · see citing works
da Rosa, J. C. F., Peres, A., Júnior, L. G., Martinez, D., & Fontanella, V. R. C. (2021) · Clinics · doi:10.6061/clinics/2021/e3056 · Cited by 12 · see citing works
Leong, Z. H., Loh, S. R. H., Leow, L. C., Ong, T. H., & Toh, S. T. (2023) · Singapore Medical Journal · doi:10.4103/singaporemedj.smj-2022-170 · Cited by 11 · see citing works
An introduction to artificial intelligence in sleep medicine
Lovejoy, C. A., Abbas, A., & Ratneswaran, D. (2021) · Journal of Thoracic Disease · doi:10.21037/jtd-21-1569 · Cited by 9 · see citing works
Chocron, A., Efraim, R., Mandel, F., Rueschman, M., Palmius, N., Penzel, T., Elbaz, M., & Behar, J. A. (2020) · Physiological Measurement · doi:10.1088/1361-6579/abb8bf · Cited by 9 · see citing works
Self-citationValidation of Oximetry for Diagnosing Obstructive Sleep Apnea in a Clinical Setting
Ito, K., Uetsu, M., & Kadotani, H. (2020) · Clocks & Sleep · doi:10.3390/clockssleep2030027 · Cited by 7 · see citing works
Zovko, K., Sadowski, Y., Perković, T., Šolić, P., Dodig, I. P., Pecotić, R., & Đogaš, Z. (2025) · Applied Sciences · doi:10.3390/app15010376 · Cited by 6 · see citing works
Gell, L. K., Mehta, K., Esmaeili, N., Taranto‐Montemurro, L., Sands, S. A., Pittman, S. D., & Azarbarzin, A. (2025) · Frontiers in Sleep · doi:10.3389/frsle.2025.1549272 · Cited by 5 · see citing works
Ma, X., Zhang, C., Feng, L., Shen, Y., Ma, J., & Wang, G. (2023) · Expert Review of Respiratory Medicine · doi:10.1080/17476348.2023.2292136 · Cited by 2 · see citing works
Apneic Event Estimation only using SpO2 Dynamics in Sleep Apnea Patients
Yoon, H., Choi, J. H., & Baek, H. J. (2020) · Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) · doi:10.1109/embc44109.2020.9176727 · Cited by 1 · see citing works
Galtieri, R., Salles, C., Kushida, C. A., Cruz, M. G. M. E., & Souza‐Machado, A. (2024) · Sleep Medicine · doi:10.1016/j.sleep.2024.08.010 · Cited by 1 · see citing works
Yield of overnight pulse oximetry in screening commercial drivers for obstructive sleep apnea
Adami, A., Tonon, D., Corica, A., Trevisan, D., Thijs, V., & Rossato, G. (2023) · Sleep And Breathing · doi:10.1007/s11325-023-02814-3
Data Based Framework for Sleep Medicine
Zovko, K., Šolić, P., Perković, T., Dodig, I. P., Kalcina, L. L., Pecotić, R., & Đogaš, Z. (2024) · International Conference on Smart and Sustainable Technologies (SpliTech) · doi:10.23919/splitech61897.2024.10612503
SnoreOxiNet: Non-contact Diagnosis of Nocturnal Hypoxemia Using Cross-Domain Acoustic Features
Yi, W., Yang, X., Xiao, L., Tu, W., Chen, X., Yang, Y., Li, X., & Jie, L. (2024) · Lecture notes in computer science · doi:10.1007/978-3-031-72353-7_11
Pan, H., Ye, J., Chen, Z., & Zhang, X. (2025) · Discover Applied Sciences · doi:10.1007/s42452-025-07129-4
A Hybrid Swarm Intelligence and Machine Learning Approach for Predictive Analysis of Sleep Disorders
Surekha, G., & Soji, E. S. (2025) · Advances in computational intelligence and robotics book series · doi:10.4018/979-8-3373-6796-5.ch001
Continuous-time Sleep Apnea Profiling from Raw PPG with CNNs and Downstream AHI EstimationPreprint
Katsaridis, F. L., Fouzas, S., & Theodorakopoulos, I. (2026) · SSRN Electronic Journal · doi:10.2139/ssrn.6188922
Application of Deep Learning Techniques for Sleep Apnea Detection and CPAP Therapy Adjustment
Vikram, A., Chathiwala, Z., & Pal, T. (2026) · IEEE International Conference for Convergence in Computing Technology (I3CTCON) · doi:10.1109/i3ctcon68242.2026.11507132
Yam, K.-M., Lim, C. Y. J., Gao, E. Y., Koh, J. H., Tan, N. K. W., Ng, A. C. W., Leong, Z. H., Phua, C. Q., Ong, T. H., Leow, L. C., et al. (2026) · Journal of Medical Internet Research · doi:10.2196/80349
Alqenae, G., Ayas, N., Boussina, A. E., & Malhotra, A. (2026) · Sleep Medicine Clinics · doi:10.1016/j.jsmc.2026.08.006
- Authors
- Behar, J. A., Palmius, N., Li, Q., Garbuio, S., Rizzatti, F. P. G., Bittencourt, L., Tufik, S., & Clifford, G. D.
- Affiliations
- Technion – Israel Institute of Technology (IL)
- University of Oxford (GB)
- Georgia Institute of Technology (US)
- Universidade Federal de São Carlos (BR)
- Universidade Federal de São Paulo (BR)
- Corresponding author
- Behar, Joachim A.
- Venue
- EClinicalMedicine
- Publisher
- Elsevier BV
- Published
- 2019-05
- Volume
- 11
- Pages
- 81-88
- ISSN
- 2589-5370 (ISSN-L)
- PMC
- PMC6611093
- OpenAlex
- W2950062353
- Cited by
- 37
- References
- 34
- Citations by year
- 2026: 4 · 2025: 4 · 2024: 4 · 2023: 9 · 2022: 5 · 2021: 6 · 2020: 5
- FWCI
- 2.74
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- EClinicalMedicine (publishedVersion, cc-by-nc-nd)
- PubMed Central (publishedVersion, cc-by-nc-nd)
- PubMed (publishedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
- Funders
- Conselho Nacional de Desenvolvimento Científico e Tecnológico (306138/2017-4, 309336/2017-1, 401569/2016-0)
- Associação Fundo de Incentivo à Pesquisa
- Fundação de Amparo à Pesquisa do Estado de São Paulo
- Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
- Topics
- Health Sciences › Medicine › Physiology › Obstructive Sleep Apnea Research
- Physical Sciences › Engineering › Biomedical Engineering › Non-Invasive Vital Sign Monitoring
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
- Keywords
- obstructive sleep apnea, sleep apnea screening, oxygen saturation, logistic regression, polysomnography, STOP-BANG questionnaire, NoSAS, sleep questionnaires, demographic factors, undiagnosed sleep apnea
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