CoChat
Sign Up
Cited by 197Chronic Obstructive Pulmonary Disease (COPD) ResearchRespiratory Support and MechanismsAsthma and respiratory diseases

The Clinical Importance of Dynamic Lung Hyperinflation in COPD

Open access
O'Donnell, Denis E., Laveneziana, Pierantonio·2006·COPD: Journal of Chronic Obstructive Pulmonary Disease
DOI 10.1080/15412550600977478
Open this paper in CoChat — free accountOpen PDF

Abstract

Lung hyperinflation commonly accompanies expiratory flow-limitation in patients with Chronic Obstructive Pulmonary Disease (COPD) and contributes importantly to dyspnea and activity limitation. It is not surprising, therefore, that lung hyperinflation has become an important therapeutic target in symptomatic COPD patients. There is increasing evidence that acute dynamic increases in lung hyperinflation, under conditions of worsening expiratory flow-limitation and increased ventilatory demand (or both) can seriously stress cardiopulmonary reserves, particularly in patients with more advanced disease. Our understanding of the physiological mechanisms of dynamic lung hyperinflation during both physical activity and exacerbations in COPD continues to grow, together with an appreciation of its serious negative mechanical and sensory consequences. In this review, we will discuss the basic pathophysiology of COPD during rest, exercise and exacerbation so as to better understand how this can be pharmacologically manipulated for the patient's benefit. Finally, we will review current concepts of the mechanisms of symptom relief and improved exercise endurance following pharmacological lung volume reduction.

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.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1080/15412550600977478

Cites

8 of 8 references verified0 citation errors · 0 not checkable

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.

A few free checks a day · papers already verified open instantly · results are public

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?

  • Nitrogen washout and helium dilution techniques underestimate FRC in the presence of severe airflow obstruction or emphysema.

    “In contrast, nitrogen washout and helium dilution techniques underestimate FRC in the presence of severe airflow obstruction or emphysema.32,140”

    From Pathogenesis of hyperinflation in chronic obstructive pulmonary disease (2014) · cites this paper as [32]

    The measurement passage (indexed as Abstract; page unavailable) equates EELV with FRC and says inert-gas dilution techniques may underestimate lung volumes because of non-communicating airways. It does not name nitrogen washout or helium dilution, specify severe airflow obstruction or emphysema as the conditions, or state that underestimation invariably occurs. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • In patients with COPD, as respiratory rate and expiratory flow increase, expiratory time can become insufficient and complete exhalation of VT to relaxation volume becomes compromised, and EELV usually increases with hyperpnea.

    “Thus, as the respiratory rate and expiratory flow increases, the expiratory time available for exhalation can become insufficient and complete exhalation of VT to the relaxation volume becomes increasingly compromised, and EELV usually increases with hyperpnea.32”

    From Pathogenesis of hyperinflation in chronic obstructive pulmonary disease (2014) · cites this paper as [32]

  • Radiographic techniques are not commonly used clinically to measure static hyperinflation in COPD because of a lack of standardization.

    “Finally, because of a lack of standardization, radiographic techniques144–147 are not commonly used clinically to measure static hyperinflation in COPD.32”

    From Pathogenesis of hyperinflation in chronic obstructive pulmonary disease (2014) · cites this paper as [32]

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

Flagged first, then by citations

Research works printed but not linked: 84

  1. Sharp JT. The respiratory muscles in emphysema. Clin Chest Med 1983; 4:421-432.
  2. Sharp JT, Goldberg NB, Druz WS, Fishman HC, Danon J. Thoraco-abdominal motion in chronic obstructive lung disease. Am Rev Resp Dis 1977; 115:47-56.
  3. Simon G, Pride NB, Jones NL, Raimondi AC. Relation be- tween abnormalities in the chest radiograph and changes in pul- monary function in chronic bronchitis and emphysema. Thorax 1973; 28:15-23.
  4. Burki NK, Krumpelman JL. Correlation of pulmonary function with the chest roentgenogram in chronic airway obstruction. Am Rev Respir Dis 1980; 121:217-223.
  5. Nakano Y, Muro S, Sakai H, Hirai T, Chin K, Tsukino M, Nishimura K, Itoh H, Par è PD, Hogg JC, Mishima M. Com- puted tomographic measurements of airway dimensions and em- physema in smokers. Correlation with lung function. Am J Respir Crit Care Med 2000; 162:1102-1108.
  6. Pellegrino R, Viegi G, Brusasco V, Crapo RO, Burgos F, Casaburi R, Coates A, van der Grinten CPM, Gustafsson P, Hankinson J, Jensen R, Johnson DC, MacIntyre N, McKay R, Miller MR, Navajas D, Pedersen OF, Wanger J. ATS/ERS Task Force: Standardisation of lung function testing: Interpretative strategies for lung function tests. Eur Respir J 2005; 26:948-968.
  7. He Z, Lam M, Webb K, O'Donnell DE. Ventilatory Constraints during Exercise in Patients with Mild COPD. Am J Respir Crit Care Med 2005; 171:A304.
  8. Leith DE, Brown R. Human lung volumes and the mechanisms that set them. Eur Respir J 1999;13:468-472.
  9. Tantucci C, Duguet A, Similowski T, Zelter M, Derenne JP, Milic-Emili J. Effect of salbutamol on dynamic hyperinflation in chronic obstructive pulmonary disease patients. Eur Respir J 1998; 12:799-804.
  10. O'Donnell DE, Revill S, Webb KA. Dynamic hyperinflation and exercise intolerance in COPD. Am J Respir Crit Care Med 2001; 164:770-777.
  11. Casanova C, Cote C, de Torres JP, Aguirre-Jaime A, Marin JM, Pinto-Plata V, Celli BR. Inspiratory-to-total lung capacity ratio predicts mortality in patients with chronic obstructive pul- monary disease. Am J Respir Crit Care Med 2005 15; 171:591- 597.
  12. O'Donnell DE, He Z, Lam M, Webb K, Fluge T, Hamilton A. Re- producibility of measurements in inspiratory capacity, dyspnea in- tensity and exercise endurance in multicentre trials in COPD (abs). Eur Respir J 2004; 24(48):P2151.
  13. O'Donnell D, Fl üge T, Gerken F, Hamilton A, Webb K, Aguilaniu B, Make B, Magnussen H. Effects of tiotropium on lung hyperin- flation, dyspnoea and exercise tolerance in COPD. Eur Respir J 2004; 23:832-840.
  14. Maltais F, Hamilton A, Marciniuk D, Hernandez P, Sciurba FC, Richter K, Kesten S, O'Donnell D. Improvements in symptom- limited exercise performance over eight hours with once-daily tiotropium in patients with COPD. Chest 2005; 128:1168-1178.
  15. Hyatt RE. Expiratory flow limitation. J Appl Physiol 1983; 55:1-8.
  16. Dawson SV, Elliott EA. Wave-speed limitation on expiratory flow-a unifying concept. J Appl Physiol 1977; 43:498-515.
  17. Pride NB. Ageing and changes in lung mechanics. Eur Respir J 2005; 26:563-565.
  18. Vinegar A, Sinnett EE, Leith DE. Dynamic mechanisms deter- mine functional residual capacity in mice. J Appl Physiol 1979; 46:867-891.
  19. Sharp JT. The respiratory muscles in chronic obstructive pul- monary disease. Am Rev Respir Dis 1986; 134:1089-1091.
  20. Demedts M. Mechanisms and consequences of hyperinflation. Eur Respir J 1990; 3:617-618.
  21. Macklem PT. Hyperinflation (editorial). Am Rev Respir Dis 1984; 129:1-2.
  22. Lougheed DM, Webb KA, O'Donnell DE. Breathlessness during induced lung hyperinflation in asthma:the role of the inspiratory threshold load. Am J Respir Crit Care Med 1995; 152:911-920.
  23. Cormier Y. Mechanisms of hyperinflation in asthma. Eur Respir J 1990; 3:619-624.
  24. Martin JG. Inspiratory muscle activity during induced hyperinfla- tion. Respir Physiol 1980; 39:303-313.
  25. Stevenson NJ, Walker PP, Costello RW, Calverley PM. Lung me- chanics and dyspnea during exacerbations of chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2005; 172:1510- 1516.
  26. O'Donnell DE, Parker CM. COPD exacerbations • 3: Pathophysi- ology. Thorax 2006; 61:354-361.
  27. Gelb AF, Guitierrez CA, Weisman IM, Newsom R, Taylor CF, Zamel N. Simplified detection of dynamic hyperinflation. Chest 2004; 126:1855-1860.
  28. O'Donnell DE, D'Arsigny C, Webb KA. Effects of hyperoxia on ventilatory limitation during exercise in advanced chronic ob- structive pulmonary disease. Am J Respir Crit Care Med 2001; 163:892-898.
  29. Grimby G, Bunn J, Mead J. Relative contribution of rib cage and abdomen to ventilation during exercise. J Appl Physiol 1968; 24:159-166.
  30. Potter WA, Olafsson S, Hyatt RE. Ventilatory mechanics and ex- piratory flow limitation during exercise in patients with obstructive lung disease. J Clin Invest 1971; 50:910-919.
  31. Stubbing DG, Pengelly LD, Morse JLC, Jones NL. Pulmonary mechanics during exercise in subjects with chronic airflow obstruc- tion. J Appl Physiol 1980; 49:511-515.
  32. Dodd DS, Brancatisano T, Engel LA. Chest wall mechanics dur- ing exercise in patients with severe chronic airway obstruction. Am Rev Respir Dis 1984; 129:33-38.
  33. Clarenbach CF, Senn O, Brack T, Kohler M, Bloch KE. Monitor- ing of ventilation during exercise by a portable respiratory inductive plethysmograph. Chest 2005; 128:1282-1290.
  34. Vogiatzis I, Georgiadou O, Golemati S, Aliverti A, Kos- mas E, Kastanakis E, Geladas N, Koutsoukou A, Nanas S, Zakynthinos S, Roussos C. Patterns of dynamic hyperinflation during exercise and recovery in patients with severe chronic ob- structive pulmonary disease. Thorax 2005; 60:723-729.
  35. Similowski T, Yan S, Gauthier AP, Macklem PT, Bellemare F. Contractile properties of the human diaphragm during chronic hy- perinflation. N Engl J Med 1991; 325:917-923.
  36. Orozco-Levi M, Gea J, Lloreta JL, F élez M, Minguella J, Serano S, Broquetas JM. Subcellular adaptation of the human diaphragm in chronic obstructive pulmonary disease. Eur Respir J 1999; 13:371-378.
  37. Levine S, Kaiser L, Leferovich J, Tikunov B. Cellular adaptations in the diaphgram in chronic obstructive pulmonary disease. N Engl J Med 1997; 337:1799-1806.
  38. Mercadier JJ, Schwartz K, Schiaffino S, Wisnewsky C, Ausoni S, Heimburger M, Marrash R, Pariente R, Aubier M. Myosin heavy chain gene expression changes in the diaphragm of patients with chronic lung hyperinflation. Am J Physiol 1998; 274:L527- 534.
  39. Decramer M. Hyperinflation and respiratory muscle interaction. Eur Respir J 1997; 10:934-941.
  40. O'Donnell DE, Webb KA. Exercise. In: Calverley PMA, MacNee W, Pride NB, Rennard SI, eds. Chronic Obstructive Pulmonary Disease, 2nd edition. London: Arnold, 2003; Chapter 18:243-269.
  41. O'Donnell DE, Chau LKL, Bertley JC, Webb KA. Qualitative aspects of exertional breathlessness in chronic airflow limitation: pathophysiologic mechanisms. Am J Respir Crit Care Med 1997; 155:109-115.
  42. O'Donnell DE, D'Arsigny C, Fitzpatrick M, Webb KA. Exercise Hypercapnia in advanced chronic obstructive pulmonary disease: the role of lung hyperinflation. Am J Respir Crit Care Med 2002; 166:663-668.
  43. Montes de Oca M, Rassulo J, Celli BR. Respiratory muscle and cardiopulmonary function during exercise in very severe COPD. Am J Respir Crit Care Med 1996; 154:1284-1289.
  44. Light RW, Mintz WM, Linden GS, Brown SE. Hemodynamics of patients with severe chronic obstructive pulmonary disease during progressive upright exercise. Am Rev Respir Dis 1984; 130:391- 395.
  45. Vizza CD, Lynch JP, Ochoa LL, Richardson G, Trulock EP. Right and left ventricular dysfunction in patients with severe pulmonary disease. Chest 1998; 113:576-583.
  46. O'Donnell DE, Hamilton AL, Webb KA. Sensory-mechanical re- lationships during high-intensity, constant-work-rate exercise in COPD. J Appl Physiol 2006; 101:1025-1035.
  47. O'Donnell DE, Lam M, Webb KA. Spirometric correlates of im- provement in exercise performance after anticholinergic therapy in COPD. Am J Respir Crit Care Med 1999; 160:524-549.
  48. O'Donnell DE, Sciurba F, Celli B, Mahler DA, Webb KA, Kalberg CJ, Knobil K. Effect of fluticasone propionate/salmeterol on lung hyperinflation and exercise endurance in COPD. Chest 2006; 130:647-656.
  49. O'Donnell DE, Bertley J, Webb KA, Conlan AA. Mechanisms of relief of exertional breathlessness following unilateral bullectomy and lung volume reduction surgery in advanced chronic airflow limitation. Chest 1996; 110:18-27.
  50. Martinez FJ, Montes de Oca M, Whyte RI, Stetz J, Gay SE, Celli BR. Lung-volume reduction improves dyspnea, dynamic hyperin- flation and respiratory muscle function. Am J Respir Crit Care Med 1997; 155:1984-1990.
  51. Barbera JA, Roca J, Ferrer A, Felez MA, Diaz O, Roger N, Rodriguez-Roisin R. Mechanisms of worsening gas exchange during acute exacerbations of chronic obstructive pulmonary dis- ease. Eur Respir J 1997; 10:1285-1291.
  52. Calverley PM. Respiratory failure in chronic obstructive pulmonary disease. Eur Respir J Suppl. 2003; 47:26s-30s.
  53. Tantucci C, Corbeil C, Chasse M, Braidy J, Matar N, Milic-Emili J. Flow resistance in patients with chronic obstructive pulmonary disease in acute respiratory failure. Am Rev Respir Dis 1991; 144:384-389.
  54. Guerin C, Coussa ML, Eissa NT, Corbeil C, Chasse M, Braidy J, Matar N, Milic-Emili J. Lung and chest wall mechanics in mechan- ically ventilated COPD patients. J Appl Physiol 1993; 74:1570- 1580.
  55. Parker CM, Voduc N, Aaron SD, Webb KA, O'Donnell DE. Phys- iological changes during symptom recovery from moderate exac- erbations of COPD. Eur Resp J 2005; 26:420-428.
  56. O'Donnell DE. Assessment of bronchodilator efficacy in symp- tomatic COPD. Is spirometry useful? Chest 2000; 117:42S- 47S.
  57. Newton M, O'Donnell DE, Forkert L. Response of lung volumes to inhaled salbutamol in a large population of patients with severe hyperinflation. Chest 2002; 121:1042-1050.
  58. Rabe KF, Bateman ED, O'Donnell D, Witte S, Bredenbr öker D, Bethke TD. Roflumilast -an oral anti-inflammatory treatment for chronic obstructive pulmonary disease: a randomised controlled trial. Lancet 2005; 366:563-571.
  59. Swanney MP, Jensen RL, Crichton DA, Beckert LE, Cardno LA, Crapo RO. FEV 6 is an acceptable surrogate for FVC in the spirometric diagnosis of airway obstruction and restriction. Am J Respir Crit Care Med 2000; 162:917-919.
  60. Celli B, ZuWallack R, Wang S, Kesten S. Improvement in resting inspiratory capacity and hyperinflation with tiotropium in COPD pa- tients with increased static lung volumes. Chest 2003; 124:1743- 1748.
  61. O'Donnell DE, Forkert L, Webb KA. Evaluation of bronchodilator responses in patients with "irreversible emphysema." Eur Respir J 2001; 18:914-920.
  62. Sciurba FC, Rogers RM, Keenan RJ, Slivka WA, Gorscan J III, Ferson PF, Holbert JM, Brown ML, Landreneau RJ. Improve- ment in pulmonary function and elastic recoil after lung-reduction surgery for diffuse emphysema. N Engl J Med 1996; 334:1095- 1099.
  63. Chrystyn H, Mulley BA, Peake MD. Dose response relation to oral theophylline in severe chronic obstructive airways disease. Brit Med J 1988; 297:1506-1510.
  64. van Noord JA, Aumann JL, Janssens E, Verhaert J, Smeets JJ, Mueller A, Cornellisen PJG. Effects of tiotropium with and without formoterol on airflow obstruction and resting hyperinflation in patients with COPD. Chest 2006; 129:509-517.
  65. Gandevia SC. The perception of motor commands on effort during muscular paralysis. Brain 1982; 105:151-195.
  66. Chen Z, Eldridge FL, Wagner PG. Respiratory associated rhyth- mic firing of midbrain neurons in cats:relation to level of respiratory drive. J Physiol 1991; 437:305-325.
  67. Campbell EJM, Howell JBL. The sensation of breathlessness. Br Med Bull 1963; 18:36-40.
  68. Chen Z, Eldridge FL, Wagner PG. Respiratory-associated thala- mic activity is related to level of respiratory drive. Respir Physiol 1992; 90:99-113.
  69. O'Donnell DE, Hong HH, Webb KA. Respiratory sensation during chest wall restriction and dead space loading in exercising men. J Appl Physiol 2000; 88:1859-1869.
  70. Davenport PW, Friedman WA, Thompson FJ, Franzen O. Respiratory-related cortical potentials evoked by inspiratory oc- clusion in humans. J Appl Physiol 1986; 60:1843-1848.
  71. Zechman FR Jr., Wiley RL. Afferent inputs to breath- ing:respiratory sensation: In: AP Fishman, ed. Handbook of Physiology, Section 3, Volume II, Part 2: The Respiratory Sys- tem. Bethesda, MD: American Physiological Society, 1986; 449- 474.
  72. Chronos N, Adams L, Guz A. Effect of hyperoxia and hypoxia on exercise-induced breathlessness in normal subjects. Clin Sci 1988; 74:531-537.
  73. Lane R, Cockcroft A, Adams L, Guz A. Arterial oxygen saturation and breathlessness in patients with chronic obstructive airways disease. Clin Sci 1987; 72:693-698.
  74. Woodcock AA, Gross ER, Geddes DM. Oxygen relieves breath- lessness in "pink puffers." Lancet 1981; 1:907-909.
  75. Stein DA, Bradley BL, Miller W. Mechanisms of oxygen effects on exercise in patients with chronic obstructive pulmonary disease. Chest 1982; 81:6-10.
  76. Libby DM, Briscoe WA, King TKC. Relief of hypoxia-related bron- choconstriction by breathing 30 percent oxygen. Am Rev Respir Dis 1981; 123:171-175.
  77. O'Donnell DE, Bain DJ, Webb KA. Factors contributing to relief of exertional breathlessness during hyperoxia in chronic airflow limitation. Am J Respir Crit Care Med 1997; 155:530-535.
  78. Somfay A, Porszasz J, Lee SM, Casaburi R. Dose-response ef- fect of oxygen on hyperinflation and exercise endurance in nonhy- poxemic COPD patients. Eur Respir J 2001; 18:77-84.
  79. Barach AL. The use of helium in the treatment of asthma and obstructive lesions in the larynx and trachea. Ann Intern Med 1935; 9:739-765.
  80. Grap é B, Channin E, Tyler JM. The effect of helium and oxygen mixtures on pulmonary resistances in emphysema. Am Rev Respir Dis 1960; 81:823-829.
  81. Wouters EF, Landser FJ, Polko AH, Visser BF. Impedance mea- surement during air and helium-oxygen breathing before and after salbutamol. Clin Exp Pharmacol Physiol 1992; 19:95-101.
  82. Swidwa DM, Montenegro HD, Goldman MD, Lutchen KR, Saidel GM. Helium-oxygen breathing in severe chronic obstruc- tive pulmonary disease. Chest 1985; 87:790-795.
  83. Meadows JA 3rd, Rodarte JR, Hyatt RE. Density dependence of maximal expiratory flow in chronic obstructive pulmonary disease. Am Rev Respir Dis 1980; 121:47-53.
  84. Marini JJ. Heliox in chronic obstructive pulmonary disease: time to lighten up? Crit Care Med 2000; 28:3086-3088. 100. Chevrolet JC. Helium oxygen mixtures in the intensive care unit. Crit Care 2001; 5:179-181. 101. McClaran SR, Wetter TJ, Pegelow DF, Dempsey JA. Role of expiratory flow limitation in determining lung volumes and ventila- tion during exercise. J Appl Physiol 1999; 86:1357-1366. 102. Palange P, Valli G, Onorati P, Antonucci R, Paoletti P, Rosato A, Manfredi F, Serra P. Effect of heliox on lung dynamic hyperinfla- tion, dyspnea, and exercise endurance capacity in COPD patients. J Appl Physiol 2004; 97:1637-1642. 103. Goto S, Porszasz J, Sakurai S, et al. Effect of helium breathing on dynamic hyperinflation, minute ventilation and exercise toler- ance in severe COPD patients. Am J Respir Crit Care Med 2004; 169:467A. 104. Laude EA, Duffy NC, Baveystock C, Dougill B, Campbell MJ, Lawson R, Jones PW, Calverley PM. The effect of helium and oxygen on exercise performance in COPD: a randomised crossover trial. Am J Respir Crit Care Med 2006; 173:865-870. 105. O'Donnell DE, Webb KA. Mechanisms of dyspnea in COPD. In: Mahler D, O'Donnell DE (eds.). Dyspnea: Mechanisms, Measure- ment, and Management, 2nd edition. Lung Biology in Health and Disease Series, Volume 208, Chapter 3. Boca Raton, FL: Taylor & Francis Group, 2005; pp. 29-58.

Cited by

Sorted by citations

Authors
O'Donnell, D. E., & Laveneziana, P.
Affiliations
Queen's University (CA)
ORCID
Laveneziana, Pierantonio
Venue
COPD: Journal of Chronic Obstructive Pulmonary Disease
Publisher
Informa UK Limited
Published
2006-01
Volume
3
Issue
4
Pages
219-232
ISSN
  • 1541-2555 (ISSN-L)
  • 1541-2563
DOI
10.1080/15412550600977478
OpenAlex
W1967981332
Cited by
197
References
8
Citations by year
2026: 15 · 2025: 7 · 2024: 7 · 2023: 13 · 2022: 10 · 2021: 12 · 2020: 7 · 2019: 11 · 2018: 14 · 2017: 14 · 2016: 14 · 2015: 8 · 2014: 9 · 2013: 11 · 2012: 8
FWCI
1.28
Type
journal article
Language
en
Open access
Locations
  • COPD Journal of Chronic Obstructive Pulmonary Disease (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Chronic Obstructive Pulmonary Disease (COPD) Research
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Respiratory Support and Mechanisms
  • Health Sciences › Medicine › Physiology › Asthma and respiratory diseases
Keywords
chronic obstructive pulmonary disease, expiratory flow limitation, COPD exacerbations, exercise intolerance, dyspnea, lung volume reduction, cardiopulmonary reserve, ventilatory demand, symptom relief
MeSH terms
Bronchodilator Agents, Exercise Therapy, Forced Expiratory Flow Rates, Humans, Oxygen Inhalation Therapy, Prognosis, Recurrence, Rest, Spirometry, Exercise, Respiratory Mechanics, Pulmonary Disease, Chronic Obstructive

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