Osteoporosis International

, Volume 20, Issue 10, pp 1633–1650

Excess mortality following hip fracture: a systematic epidemiological review

  • B. Abrahamsen
  • T. van Staa
  • R. Ariely
  • M. Olson
  • C. Cooper
Review

Abstract

Summary This systematic literature review has shown that patients experiencing hip fracture after low-impact trauma are at considerable excess risk for death compared with nonhip fracture/community control populations. The increased mortality risk may persist for several years thereafter, highlighting the need for interventions to reduce this risk.

Patients experiencing hip fracture after low-impact trauma are at considerable risk for subsequent osteoporotic fractures and premature death. We conducted a systematic review of the literature to identify all studies that reported unadjusted and excess mortality rates for hip fracture. Although a lack of consistent study design precluded any formal meta-analysis or pooled analysis of the data, we have shown that hip fracture is associated with excess mortality (over and above mortality rates in nonhip fracture/community control populations) during the first year after fracture ranging from 8.4% to 36%. In the identified studies, individuals experienced an increased relative risk for mortality following hip fracture that was at least double that for the age-matched control population, became less pronounced with advancing age, was higher among men than women regardless of age, was highest in the days and weeks following the index fracture, and remained elevated for months and perhaps even years following the index fracture. These observations show that patients are at increased risk for premature death for many years after a fragility-related hip fracture and highlight the need to identify those patients who are candidates for interventions to reduce their risk.

Keywords

Excess mortality Femoral neck fracture Fragility-related fracture Hip fracture Osteoporotic hip fracture Systematic review 

References

  1. 1.
    Dennison E, Mohamed A, Cooper C (2006) Epidemiology of osteoporosis. Rheum Dis Clin North Am 32:617–629PubMedGoogle Scholar
  2. 2.
    Melton LJ 3rd (2003) Epidemiology worldwide. Endocrinol Metab Clin North Am 32:1–13PubMedGoogle Scholar
  3. 3.
    Johnell O, Kanis JA (2006) An estimate of the worldwide prevalence and disability associated with osteoporotic fractures. Osteoporos Int 17:1726–1733PubMedGoogle Scholar
  4. 4.
    Gullberg B, Johnell O, Kanis JA (1997) World-wide projections for hip fracture. Osteoporos Int 7:407–413PubMedGoogle Scholar
  5. 5.
    Johnell O, Kanis JA (2004) An estimate of the worldwide prevalence, mortality and disability associated with hip fracture. Osteoporos Int 15:897–902PubMedGoogle Scholar
  6. 6.
    Bergström U, Bjornstig U, Stenlund H et al (2008) Fracture mechanisms and fracture pattern in men and women aged 50 years and older: a study of a 12-years population-based register, Umea, Sweden. Osteoporos Int 19:1267–1273PubMedGoogle Scholar
  7. 7.
    Tarantino U, Cannata G, Lecce D et al (2007) Incidence of fragility fractures. Aging Clin Exp Res 19(suppl 4):7–11PubMedGoogle Scholar
  8. 8.
    Kamel HK (2005) Secondary prevention of hip fractures among the hospitalized elderly: are we doing enough? J Clin Rheumatol 11:68–71PubMedGoogle Scholar
  9. 9.
    Petrella RJ, Jones TJ (2006) Do patients receive recommended treatment of osteoporosis following hip fracture in primary care? BMC Fam Pract 7:31PubMedGoogle Scholar
  10. 10.
    Siris ES, Bilezikian JP, Rubin MR et al (2003) Pins and plaster aren't enough: a call for the evaluation and treatment of patients with osteoporotic fractures. J Clin Endocrinol Metab 88:3482–3486PubMedGoogle Scholar
  11. 11.
    Kanis JA, Oden A, Johnell O et al (2003) The components of excess mortality after hip fracture. Bone 32:468–473PubMedGoogle Scholar
  12. 12.
    Beer C, Xiao J, Flicker L et al (2007) Long-term mortality following stroke, myocardial infarction and fractured neck of femur in Western Australia. Intern Med J 37:815–819PubMedGoogle Scholar
  13. 13.
    Farahmand BY, Michaëlsson K, Ahlbom A et al (2005) Survival after hip fracture. Osteoporos Int 16:1583–1590PubMedGoogle Scholar
  14. 14.
    Fransen M, Woodward M, Norton R et al (2002) Excess mortality or institutionalization after hip fracture: men are at greater risk than women. J Am Geriatr Soc 50:685–690PubMedGoogle Scholar
  15. 15.
    Giversen IM (2007) Time trends of mortality after first hip fractures. Osteoporos Int 18:721–732PubMedGoogle Scholar
  16. 16.
    Paksima N, Koval KJ, Aharanoff G et al (2008) Predictors of mortality after hip fracture: a 10-year prospective study. Bull NYU Hosp Jt Dis 66:111–117PubMedGoogle Scholar
  17. 17.
    Parker MJ, Anand JK (1991) What is the true mortality of hip fractures? Public Health 105:443–446PubMedGoogle Scholar
  18. 18.
    Poór G, Atkinson EJ, O'Fallon WM et al (1995) Determinants of reduced survival following hip fractures in men. Clin Orthop Relat Res 319:260–265PubMedGoogle Scholar
  19. 19.
    Rapp K, Becker C, Lamb SE et al (2008) Hip fractures in institutionalized elderly people: incidence rates and excess mortality. J Bone Miner Res 23:1825–1831PubMedGoogle Scholar
  20. 20.
    Sexson SB, Lehner JT (1987) Factors affecting hip fracture mortality. J Orthop Trauma 1:298–305PubMedGoogle Scholar
  21. 21.
    Tosteson AN, Gottlieb DJ, Radley DC et al (2007) Excess mortality following hip fracture: the role of underlying health status. Osteoporos Int 18:1463–1472PubMedGoogle Scholar
  22. 22.
    Vestergaard P, Rejnmark L, Mosekilde L (2007) Has mortality after a hip fracture increased? J Am Geriatr Soc 55:1720–1726PubMedGoogle Scholar
  23. 23.
    Weiss NS, Liff JM, Ure CL et al (1983) Mortality in women following hip fracture. J Chronic Dis 36:879–882PubMedGoogle Scholar
  24. 24.
    Wolinsky FD, Fitzgerald JF, Stump TE (1997) The effect of hip fracture on mortality, hospitalization, and functional status: a prospective study. Am J Public Health 87:398–403PubMedGoogle Scholar
  25. 25.
    Empana JP, Dargent-Molina P, Bréart G, for the EPIDOS Group (2004) Effect of hip fracture on mortality in elderly women: the EPIDOS prospective study. J Am Geriatr Soc 52:685–690PubMedGoogle Scholar
  26. 26.
    Forsén L, Sogaard AJ, Meyer HE et al (1999) Survival after hip fracture: short- and long-term excess mortality according to age and gender. Osteoporos Int 10:73–78PubMedGoogle Scholar
  27. 27.
    Johnell O, Kanis JA, Odén A et al (2004) Mortality after osteoporotic fractures. Osteoporos Int 15:38–42PubMedGoogle Scholar
  28. 28.
    Vestergaard P, Rejnmark L, Mosekilde L (2007) Increased mortality in patients with a hip fracture—effect of pre-morbid conditions and post-fracture complications. Osteoporos Int 18:1583–1593PubMedGoogle Scholar
  29. 29.
    Beals RK (1972) Survival following hip fracture. Long follow-up of 607 patients. J Chronic Dis 25:235–244PubMedGoogle Scholar
  30. 30.
    Endo Y, Aharonoff GB, Zuckerman JD et al (2005) Gender differences in patients with hip fracture: a greater risk of morbidity and mortality in men. J Orthop Trauma 19:29–35PubMedGoogle Scholar
  31. 31.
    Dahl E (1980) Mortality and life expectancy after hip fractures. Acta Orthop Scand 51:163–170PubMedCrossRefGoogle Scholar
  32. 32.
    Allaf N, Lovell M (2004) Annual review of fractured neck of femur mortality rates: is this a true picture? Ann R Coll Surg Engl 86:347–348PubMedGoogle Scholar
  33. 33.
    Bass E, French DD, Bradham DD et al (2007) Risk-adjusted mortality rates of elderly veterans with hip fractures. Ann Epidemiol 17:514–519PubMedGoogle Scholar
  34. 34.
    Bjørgul K, Reikerås O (2007) Outcome of undisplaced and moderately displaced femoral neck fractures. Acta Orthop 78:498–504PubMedGoogle Scholar
  35. 35.
    Deakin DE, Boulton C, Moran CG (2007) Mortality and causes of death among patients with isolated limb and pelvic fractures. Injury 38:312–317PubMedGoogle Scholar
  36. 36.
    Fisher ES, Baron JA, Malenka DJ et al (1991) Hip fracture incidence and mortality in New England. Epidemiology 2:116–122PubMedGoogle Scholar
  37. 37.
    Lawrence VA, Hilsenbeck SG, Noveck H et al (2002) Medical complications and outcomes after hip fracture repair. Arch Intern Med 162:2053–2057PubMedGoogle Scholar
  38. 38.
    Nather A, Seow CS, Iau P et al (1995) Morbidity and mortality for elderly patients with fractured neck of femur treated by hemiarthroplasty. Injury 26:187–190PubMedGoogle Scholar
  39. 39.
    Roberts SE, Goldacre MJ (2003) Time trends and demography of mortality after fractured neck of femur in an English population, 1968–98: database study. BMJ 327:771–775PubMedGoogle Scholar
  40. 40.
    Schrøder HM, Erlandsen M (1993) Age and sex as determinants of mortality after hip fracture: 3,895 patients followed for 2.5–18.5 years. J Orthop Trauma 7:525–531PubMedGoogle Scholar
  41. 41.
    Walker N, Norton R, Vander Hoorn S et al (1999) Mortality after hip fracture: regional variations in New Zealand. N Z Med J 112:269–271PubMedGoogle Scholar
  42. 42.
    Magaziner J, Lydick E, Hawkes W et al (1997) Excess mortality attributable to hip fracture in white women aged 70 years and older. Am J Public Health 87:1630–1636PubMedGoogle Scholar
  43. 43.
    Richmond J, Aharonoff GB, Zuckerman JD et al (2003) Mortality risk after hip fracture. J Orthop Trauma 17(8):S2–S5PubMedGoogle Scholar
  44. 44.
    Tsuboi M, Hasegawa Y, Suzuki S et al (2007) Mortality and mobility after hip fracture in Japan: a ten-year follow-up. J Bone Joint Surg Br 89:461–466PubMedGoogle Scholar
  45. 45.
    Jiang HX, Majumdar SR, Dick DA et al (2005) Development and initial validation of a risk score for predicting in-hospital and 1-year mortality in patients with hip fractures. J Bone Miner Res 20:494–500PubMedGoogle Scholar
  46. 46.
    Benet-Travé J, Domínguez-García A, Sales-Pérez JM et al (1997) In-hospital case-fatality of aged patients with hip fracture in Catalonia, Spain. Eur J Epidemiol 13:681–686PubMedGoogle Scholar
  47. 47.
    Holt G, Smith R, Duncan K et al (2008) Gender differences in epidemiology and outcome after hip fracture: evidence from the Scottish Hip Fracture Audit. J Bone Joint Surg Br 90:480–483PubMedGoogle Scholar
  48. 48.
    Cree M, Soskolne CL, Belseck E et al (2000) Mortality and institutionalization following hip fracture. J Am Geriatr Soc 48:283–288PubMedGoogle Scholar
  49. 49.
    Boereboom FT, Raymakers JA, Duursma SA (1992) Mortality and causes of death after hip fractures in The Netherlands. Neth J Med 41:4–10PubMedGoogle Scholar
  50. 50.
    Cipitria JA, Sosa MM, Pezzotto SM et al (1997) Outcome of hip fractures among elderly subjects. Medicina (B Aires) 57:530–534Google Scholar
  51. 51.
    Hindmarsh DM, Hayen A, Finch CF, Close JC (2008) Relative survival after hospitalisation for hip fracture in older people in New South Wales, Australia. Osteoporos Int 20:221–229PubMedGoogle Scholar
  52. 52.
    Myers AH, Robinson EG, Van Natta ML et al (1991) Hip fractures among the elderly: factors associated with in-hospital mortality. Am J Epidemiol 134:1128–1137PubMedGoogle Scholar
  53. 53.
    Roos LL, Walld RK, Romano PS et al (1996) Short-term mortality after repair of hip fracture. Do Manitoba elderly do worse? Med Care 34:310–326PubMedGoogle Scholar
  54. 54.
    Mullen JO, Mullen NL (1992) Hip fracture mortality. A prospective, multifactorial study to predict and minimize death risk. Clin Orthop Relat Res 280:214–222PubMedGoogle Scholar
  55. 55.
    Petitti DB, Sidney S (1989) Hip fracture in women. Incidence, in-hospital mortality, and five-year survival probabilities in members of a prepaid health plan. Clin Orthop Relat Res 246:150–155PubMedGoogle Scholar
  56. 56.
    Hasegawa Y, Suzuki S, Wingstrand H (2007) Risk of mortality following hip fracture in Japan. J Orthop Sci 12:113–117PubMedGoogle Scholar
  57. 57.
    Miller CW (1978) Survival and ambulation following hip fracture. J Bone Joint Surg Am 60:930–934PubMedGoogle Scholar
  58. 58.
    Wood DJ, Ions GK, Quinby JM et al (1992) Factors which influence mortality after subcapital hip fracture. J Bone Joint Surg Br 74:199–202PubMedGoogle Scholar
  59. 59.
    Shah MR, Aharonoff GB, Wolinsky P et al (2001) Outcome after hip fracture in individuals ninety years of age and older. J Orthop Trauma 15:34–39PubMedGoogle Scholar
  60. 60.
    Holt G, Smith R, Duncan K et al (2008) Early mortality after surgical fixation of hip fractures in the elderly: an analysis of data from the scottish hip fracture audit. J Bone Joint Surg Br 90:1357–1363PubMedGoogle Scholar
  61. 61.
    Mortimore E, Haselow D, Dolan M et al (2008) Amount of social contact and hip fracture mortality. J Am Geriatr Soc 56:1069–1074PubMedGoogle Scholar
  62. 62.
    Kreutzfeldt J, Haim M, Bach E (1984) Hip fracture among the elderly in a mixed urban and rural population. Age Ageing 13:111–119PubMedGoogle Scholar
  63. 63.
    van de Kerkhove MP, Antheunis PS, Luitse JS et al (2008) Hip fractures in nonagenarians: perioperative mortality and survival. Injury 39:244–248PubMedGoogle Scholar
  64. 64.
    Roche JJ, Wenn RT, Sahota O et al (2005) Effect of comorbidities and postoperative complications on mortality after hip fracture in elderly people: prospective observational cohort study. BMJ 331:1374PubMedGoogle Scholar
  65. 65.
    Boufous S, Finch CF, Lord SR (2004) Incidence of hip fracture in New South Wales: are our efforts having an effect? Med J Aust 180:623–626PubMedGoogle Scholar
  66. 66.
    Orces CH, Lee S, Bradshaw B (2002) Sex and ethnic differences in hip fracture-related mortality in Texas, 1990 through 1998. Tex Med 98:56–58PubMedGoogle Scholar
  67. 67.
    Rosencher N, Vielpeau C, Emmerich J (2005) Venous thromboembolism and mortality after hip fracture surgery: the ESCORTE study. J Thromb Haemost 3:2006–2014PubMedGoogle Scholar
  68. 68.
    Shiga T, Wajima Z, Ohe Y (2008) Is operative delay associated with increased mortality of hip fracture patients? Systematic review, meta-analysis, and meta-regression. Can J Anaesth 55:146–154PubMedCrossRefGoogle Scholar
  69. 69.
    Sircar P, Godkar D, Mahgerefteh S et al (2007) Morbidity and mortality among patients with hip fractures surgically repaired within and after 48 hours. Am J Ther 14:508–513PubMedGoogle Scholar
  70. 70.
    Gdalevich M, Cohen D, Yosef D et al (2004) Morbidity and mortality after hip fracture: the impact of operative delay. Arch Orthop Trauma Surg 124:334–340PubMedGoogle Scholar
  71. 71.
    Rogers FB, Shackford SR, Keller MS (1995) Early fixation reduces morbidity and mortality in elderly patients with hip fractures from low-impact falls. J Trauma 39:261–265PubMedGoogle Scholar
  72. 72.
    Stavrou ZP, Erginousakis DA, Loizides AA et al (1997) Mortality and rehabilitation following hip fracture. A study of 202 elderly patients. Acta Orthop Scand Suppl 275:89–91PubMedGoogle Scholar
  73. 73.
    Majumdar SR, Beaupre LA, Johnston DW et al (2006) Lack of association between mortality and timing of surgical fixation in elderly patients with hip fracture: results of a retrospective population-based cohort study. Med Care 44:552–559PubMedGoogle Scholar
  74. 74.
    Orosz GM, Magaziner J, Hannan EL et al (2004) Association of timing of surgery for hip fracture and patient outcomes. JAMA 291:1738–1743PubMedGoogle Scholar
  75. 75.
    Moran CG, Wenn RT, Sikand M et al (2005) Early mortality after hip fracture: is delay before surgery important? J Bone Joint Surg Am 87:483–489PubMedGoogle Scholar
  76. 76.
    Doruk H, Mas MR, Yildiz C et al (2004) The effect of the timing of hip fracture surgery on the activity of daily living and mortality in elderly. Arch Gerontol Geriatr 39:179–185PubMedGoogle Scholar
  77. 77.
    Wehren LE, Hawkes WG, Orwig DL et al (2003) Gender differences in mortality after hip fracture: the role of infection. J Bone Miner Res 18:2231–2237PubMedGoogle Scholar
  78. 78.
    Owens WD, Felts JA, Spitznagel EL Jr (1978) ASA physical status classifications: a study of consistency of ratings. Anesthesiology 49:239–243PubMedGoogle Scholar
  79. 79.
    Diamond TH, Thornley SW, Sekel R et al (1997) Hip fracture in elderly men: prognostic factors and outcomes. Med J Aust 167:412–415PubMedGoogle Scholar
  80. 80.
    Berry SD, Samelson EJ, Hannan MT et al (2007) Second hip fracture in older men and women. The Framingham Study. Arch Intern Med 167:1971–1976PubMedGoogle Scholar
  81. 81.
    Chapurlat RD, Bauer DC, Nevitt M et al (2003) Incidence and risk factors for a second hip fracture in elderly women. The Study of Osteoporotic Fractures. Osteoporos Int 14:130–136PubMedGoogle Scholar
  82. 82.
    Elliot-Gibson V, Bogoch ER, Jamal SA et al (2004) Practice patterns in the diagnosis and treatment of osteoporosis after a fragility fracture: a systematic review. Osteoporos Int 15:767–778PubMedGoogle Scholar
  83. 83.
    Lönnroos E, Kautiainen H, Karppi P et al (2007) Incidence of second hip fracture. A population-based study. Osteoporos Int 18:1279–1285PubMedGoogle Scholar
  84. 84.
    Ip D, Ip FK (2006) Elderly patients with two episodes of fragility hip fractures form a special subgroup. J Orthop Surg (Hong Kong) 14:245–248Google Scholar
  85. 85.
    Andrade SE, Majumdar SR, Chan KA et al (2003) Low frequency of treatment of osteoporosis among postmenopausal women following a fracture. Arch Intern Med 163:2052–2057PubMedGoogle Scholar
  86. 86.
    Follin SL, Black JN, McDermott MT (2003) Lack of diagnosis and treatment of osteoporosis in men and women after hip fracture. Pharmacotherapy 23:190–198PubMedGoogle Scholar
  87. 87.
    Harrington JT, Broy SB, Derosa AM et al (2002) Hip fracture patients are not treated for osteoporosis: a call to action. Arthritis Rheum 47:651–654PubMedGoogle Scholar
  88. 88.
    Juby AG, De Geus-Wenceslau CM (2002) Evaluation of osteoporosis treatment in seniors after hip fracture. Osteoporos Int 13:205–210PubMedGoogle Scholar
  89. 89.
    Kiebzak GM, Beinart GA, Perser K et al (2002) Undertreatment of osteoporosis in men with hip fracture. Arch Intern Med 162:2217–2222PubMedGoogle Scholar
  90. 90.
    Murray AW, McQuillan C, Kennon B et al (2005) Osteoporosis risk assessment and treatment intervention after hip or shoulder fracture. A comparison of two centers in the United Kingdom. Injury 36:1080–1084PubMedGoogle Scholar
  91. 91.
    Egan M, Jaglal S, Byrne K et al (2008) Factors associated with a second hip fracture: a systematic review. Clin Rehabil 22:272–282PubMedGoogle Scholar
  92. 92.
    Lyles KW, Colon-Emeric CS, Magaziner JS et al (2007) Zoledronic acid and clinical fractures and mortality after hip fracture. N Engl J Med 357:1799–1809PubMedGoogle Scholar
  93. 93.
    Kannus P, Uusi-Rasi K, Palvanen M et al (2005) Non-pharmacological means to prevent fractures among older adults. Ann Med 37:303–310PubMedGoogle Scholar
  94. 94.
    Eneroth M, Olsson UB, Thorngren KG (2006) Nutritional supplementation decreases hip fracture-related complications. Clin Orthop Relat Res 451:212–217PubMedGoogle Scholar
  95. 95.
    Duncan DG, Beck SJ, Hood K et al (2006) Using dietetic assistants to improve the outcome of hip fracture: a randomised controlled trial of nutritional support in an acute trauma ward. Age Ageing 35:148–153PubMedGoogle Scholar
  96. 96.
    Naglie G, Tansey C, Kirkland JL et al (2002) Interdisciplinary inpatient care for elderly people with hip fracture: a randomized controlled trial. CMAJ 167:25–32PubMedGoogle Scholar
  97. 97.
    Vidan M, Serra JA, Moreno C et al (2005) Efficacy of a comprehensive geriatric intervention in older patients hospitalized for hip fracture: a randomized, controlled trial. J Am Geriatr Soc 53:1476–1482PubMedGoogle Scholar
  98. 98.
    Roder F, Schwab M, Aleker T et al (2003) Proximal femur fracture in older patients—rehabilitation and clinical outcomes. Age Ageing 32:74–80PubMedGoogle Scholar
  99. 99.
    Aharonoff GB, Koval KJ, Skovron ML, Zuckerman JD (1997) Hip fractures in the elderly: predictors of one year mortality. J Orthop Trauma 11:162–165PubMedGoogle Scholar
  100. 100.
    Bass E, Campbell RR, Werner DC et al (2004) Inpatient mortality of hip fracture patients in the Veterans Health Administration. Rehabil Nurs 29:215–220PubMedGoogle Scholar
  101. 101.
    Eastwood EA, Magaziner J, Wang J et al (2002) Patients with hip fracture: subgroups and their outcomes. J Am Geriatr Soc 50:1240–1249PubMedGoogle Scholar
  102. 102.
    Goldacre MJ, Roberts SE, Yeates D (2002) Mortality after admission to hospital with fractured neck of femur: database study. BMJ 325:868–869PubMedGoogle Scholar
  103. 103.
    Heikkinen T, Parker M, Jalovaara P (2001) Hip fractures in Finland and Great Britain—a comparison of patient characteristics and outcomes. Int Orthop 25:349–354PubMedGoogle Scholar
  104. 104.
    Kernek CB, Baele JR, Throop FB, Pierce RO (1990) Comparison of hip fracture mortality: 1946 to 1955 vs. 1982 to 1986. Indiana Med 83:332–335PubMedGoogle Scholar
  105. 105.
    McColl A, Roderick P, Cooper C (1998) Hip fracture incidence and mortality in an English Region: a study using routine National Health Service data. J Public Health Med 20:196–205PubMedGoogle Scholar
  106. 106.
    Radcliff TA, Henderson WG, Stoner TJ et al (2008) Patient risk factors, operative care, and outcomes among older community-dwelling male veterans with hip fracture. J Bone Joint Surg Am 90:34–42PubMedGoogle Scholar

Copyright information

© International Osteoporosis Foundation and National Osteoporosis Foundation 2009

Authors and Affiliations

  • B. Abrahamsen
    • 1
  • T. van Staa
    • 2
    • 3
  • R. Ariely
    • 4
  • M. Olson
    • 5
  • C. Cooper
    • 6
    • 7
  1. 1.Department of Internal Medicine and EndocrinologyCopenhagen University Hospital GentofteHellerupDenmark
  2. 2.General Practice Research DatabaseLondonUK
  3. 3.Utrecht Institute for Pharmaceutical SciencesUtrecht UniversityUtrechtThe Netherlands
  4. 4.Novartis Pharmaceutical CorporationEast HanoverUSA
  5. 5.Novartis Pharma AGBaselSwitzerland
  6. 6.MRC Epidemiology Resource CentreUniversity of SouthamptonSouthamptonUK
  7. 7.NIHR Biomedical Research Unit in Musculoskeletal SciencesUniversity of OxfordOxfordUK

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