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Travel burden and clinical presentation of retinoblastoma: analysis of 1024 patients from 43 African countries and 518 patients from 40 European countries
  1. Ido Didi Fabian1,2,
  2. Andrew W Stacey3,
  3. Allen Foster1,
  4. Tero T Kivelä4,
  5. Francis L. Munier5,
  6. Naama Keren-Froim6,
  7. Nir Gomel7,
  8. Nathalie Cassoux8,
  9. Mandeep S Sagoo9,
  10. M Ashwin Reddy10,
  11. Lamis Al Harby10,
  12. Marcia Zondervan1,
  13. Covadonga Bascaran1,
  14. Elhassan Abdallah11,
  15. Shehu U Abdullahi12,
  16. Sahadatou Adamou Boubacar13,
  17. Dupe S Ademola-Popoola14,
  18. Adedayo Adio15,
  19. Ada E Aghaji16,
  20. Silvia Alarcón Portabella17,
  21. Amadou I Alfa Bio18,
  22. Amany M Ali19,
  23. Donjeta B Alia20,
  24. Charlotta All-Eriksson21,
  25. Argentino A Almeida22,
  26. Khalifa M Alsawidi23,
  27. Romanzo Antonino24,
  28. Nicholas J Astbury1,
  29. Rose Atsiaya25,
  30. Julia Balaguer26,
  31. Walentyna Balwierz27,
  32. Honorio Barranco26,
  33. Maja Beck Popovic28,
  34. Sarra Benmiloud29,
  35. Nissrine Bennani Guebessi30,
  36. Rokia C Berete31,
  37. Shelley J Biddulph32,
  38. Eva M Biewald33,
  39. Sharon Blum2,
  40. Nadia Bobrova34,
  41. Marianna Boehme33,
  42. Norbert Bornfeld33,
  43. Gabrielle C Bouda35,
  44. Hédi Bouguila36,
  45. Amaria Boumedane37,
  46. Bénédicte G Brichard38,
  47. Michael Capra l39,
  48. Guilherme Castela40,
  49. Jaume Català-Mora41,
  50. Guillermo L Chantada41,
  51. Violeta S Chernodrinska42,
  52. Faraja S Chiwanga43,
  53. Krzysztof Cieslik44,
  54. Codruta Comsa45,
  55. Maria G Correa Llano41,
  56. Monika Csóka46,
  57. Isac V Da Gama47,
  58. Alan Davidson48,
  59. Patrick De Potter38,
  60. Laurence Desjardins49,
  61. Monica D Dragomir45,
  62. Magritha Du Bruyn50,
  63. Asmaa El Kettani30,
  64. Amal M Elbahi23,
  65. Dina Elgalaly51,
  66. Alaa M Elhaddad51,
  67. Moawia M Ali Elhassan52,
  68. Mahmoud M Elzembely19,
  69. Vera A Essuman53,
  70. Ted Grimbert A Evina54,
  71. Oluyemi Fasina55,
  72. Ana Fernández-Teijeiro56,
  73. Moira Gandiwa57,
  74. David García Aldana58,
  75. Jennifer A Geel32,59,
  76. Zelalem Gizachew60,
  77. Pernille A Gregersen61,
  78. Koffi M Guedenon62,
  79. Theodora Hadjistilianou63,
  80. Sadiq Hassan12,
  81. Stanislava Hederova64,
  82. Laila Hessissen65,
  83. Diriba F Hordofa66,
  84. Marlies Hummlen67,
  85. Kristina Husakova64,
  86. Russo Ida24,
  87. Vesna R Ilic68,
  88. Helen Jenkinson69,
  89. Theophile B Amani Kabesha70,
  90. Rolande L Kabore35,
  91. Abubakar Kalinaki71,
  92. Noa Kapelushnik2,
  93. Tamar Kardava72,
  94. Pavlin Kroumov Kemilev42,
  95. Tomas Kepak73,
  96. Zaza Khotenashvili72,
  97. Artur Klett74,
  98. Jess Elio Kosh Komba Palet75,
  99. Dalia Krivaitiene76,
  100. Mariana Kruger77,
  101. Alice Kyara43,
  102. Eva S Lachmann78,
  103. Slobodanka Latinović79,
  104. Karin Lecuona80,
  105. Robert M Lukamba81,
  106. Livia Lumbroso49,
  107. Lesia Lysytsia82,
  108. Erika Maka46,
  109. Mayuri Makan83,
  110. Chatonda Manda57,
  111. Nieves Martín Begue17,
  112. Ibrahim O Matende25,
  113. Marchelo Matua84,
  114. Ismail Mayet32,
  115. Freddy B Mbumba85,
  116. Aemero A Mengesha86,
  117. Edoardo Midena87,
  118. Furahini G Mndeme88,
  119. Ahmed A Mohamedani89,
  120. Annette C Moll90,
  121. Claude Moreira91,
  122. Mchikirwa S Msina88,
  123. Gerald Msukwa57,
  124. Kangwa I Muma92,
  125. Gabriela Murgoi45,
  126. Kareem O Musa93,
  127. Hamzah Mustak80,
  128. Okwen M Muyen94,
  129. Gita Naidu32,
  130. Larisa Naumenko95,
  131. Paule Aïda Ndoye Roth96,
  132. Vladimir Neroev97,
  133. Marina Nikitovic68,
  134. Elizabeth D Nkanga98,
  135. Henry Nkumbe54,
  136. Mutale Nyaywa99,
  137. Ghislaine Obono-Obiang100,
  138. Ngozi C Oguego16,
  139. Andrzej Olechowski44,
  140. Alexander Hugo Oscar42,
  141. Peter Osei-Bonsu101,
  142. Sally L Painter69,
  143. Vivian Paintsil101,
  144. Luisa Paiva102,
  145. Ruzanna Papyan103,
  146. Raffaele Parrozzani87,
  147. Manoj Parulekar69,
  148. Katarzyna Pawinska-Wasikowska27,
  149. Sanja Perić104,
  150. Remezo Philbert105,
  151. Pavel Pochop106,
  152. Vladimir G Polyakov107,108,
  153. Manca T Pompe109,
  154. Jonathan J Pons110,
  155. Léa Raobela111,
  156. Lorna A Renner112,
  157. David Reynders113,
  158. Dahiru Ribadu114,
  159. Mussagy M Riheia115,
  160. Petra Ritter-Sovinz116,
  161. Svetlana Saakyan97,
  162. Azza MA Said117,
  163. Sonsoles San Román Pacheco118,
  164. Trish A Scanlan43,
  165. Judy Schoeman113,
  166. Stefan Seregard21,
  167. Sadik T Sherief60,
  168. Sidi Sidi Cheikh119,
  169. Sónia Silva40,
  170. Tetyana Sorochynska34,
  171. Grace Ssali120,
  172. Christina Stathopoulos5,
  173. Branka Stirn Kranjc109,
  174. David K Stones121,
  175. Karel Svojgr122,
  176. Fatoumata Sylla123,
  177. Gevorg Tamamyan103,
  178. Alketa Tandili20,
  179. Bekim Tateshi124,
  180. Tuyisabe Theophile125,
  181. Fousseyni Traoré126,
  182. Harba Tyau-Tyau127,
  183. Ali B Umar12,
  184. Steen F Urbak128,
  185. Tatiana L Ushakova107,108,
  186. Sandra Valeina129,
  187. Milo van Hoefen Wijsard90,
  188. Nevyana V Veleva-Krasteva42,
  189. Maris Viksnins129,
  190. Werner Wackernagel130,
  191. Keith Waddell84,
  192. Patricia D Wade131,
  193. Amina H Wali Nigeria132,
  194. Amelia DC Wime102,
  195. Charlotte Wolley Dod17,
  196. Jenny M Yanga133,
  197. Vera A Yarovaya134,
  198. Andrey A Yarovoy134,
  199. Ekhtelbenina Zein135,
  200. Shirley Sharabi136,
  201. Katsiaryna Zhilyaeva95,
  202. Othman AO Ziko117,
  203. Richard Bowman137
  1. 1 International Centre for Eye Health, London School of Hygiene and Tropical Medicine, London, UK
  2. 2 The Goldschleger Eye Institute, Sheba Medical Center, Tel Hashomer, Tel-Aviv University, Tel-Aviv, Israel
  3. 3 Department of Ophthalmology, University of Washington, Seattle, WA, US
  4. 4 Ocular Oncology Service, Department of Ophthalmology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
  5. 5 Jules-Gonin Eye Hospital, Fondation Asile de Aveugles, University of Lausanne, Lausanne, Switzerland
  6. 6 Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
  7. 7 Division of Ophthalmology, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
  8. 8 Institut curie, université de Paris medicine Paris V Descartes, Paris, France
  9. 9 NIHR Biomedical Research Center for Ophthalmology at Moorfields Eye Hospital and UCL Institute of Ophthalmology and London Retinoblastoma Service, Royal London Hospital, London, UK
  10. 10 The Royal London Hospital, Barts Health NHS Trust, and Moorfields Eye Hospital NHS Foundation Trust, London, UK
  11. 11 Ophthalmology Department of Rabat, Mohammed V university, Rabat, Morocco
  12. 12 Bayero University, Aminu Kano Teaching Hospital, Kano, Nigeria
  13. 13 National Hospital of Niamey, Niamey, Niger
  14. 14 University of Ilorin and University of IlorinTeaching Hospital, Ilorin, Kwara State, Nigeria
  15. 15 Department of Ophthalmology, University of Port Harcourt Teaching Hospital, Port Harcourt, Nigeria
  16. 16 Department of Ophthalmology, College of Medicine, University of Nigeria, Enugu, Nigeria
  17. 17 Department of Pediatric Ophthalmology, Hospital Vall d’Hebron, Barcelona, Spain
  18. 18 University of Parakou, Parakou, Benin
  19. 19 Pediatric Oncology Department, South Egypt Cancer Institute, Assiut University, Assiut, Egypt
  20. 20 University Hospital Center ‘Mother Theresa’, Tirana, Albania
  21. 21 St Erik Eye Hospital, Stockholn, Sweden
  22. 22 Beira Central Hospital, Beira, Mozambique
  23. 23 Tripoli Eye Hospital, Tripoli University, Tripoli, Libya
  24. 24 Bambino Gesù IRCCS Children’s Hospital, Rome, Italy
  25. 25 Light House For Christ Eye Center, Mombasa, Kenya
  26. 26 Pediatric Oncology Unit, Hospital Universitario y Politécnico La Fe, Valencia, Spain
  27. 27 Institute of Pediatrics, Jagiellonian University Medical College, Childrens University Hospital of Krakow, Krakow, Poland
  28. 28 Unit of Pediatric Hematology-Oncology, University Hospital CHUV, Lausanne, Switzerland
  29. 29 Department of Pediatric Oncology, University Hassan II Fès, Fez, Morocco
  30. 30 Center Hospitalier et Universitaire Ibn Rochd, Casablanca, Morocco
  31. 31 Ophthalmologic Department of the Teaching Hospital of Treichville, Abidjan, Côte d’ivoire
  32. 32 University of the Witwatersrand, Johannesburg, South Africa
  33. 33 University Hospital Essen, Department of Ophthalmology, University Duisburg-Essen, Essen, Germany
  34. 34 The Filatov Institute of Eye diseases and Tissue Therapy, Odessa, Ukraine
  35. 35 Center Hospitalier Universitaire Yalgado Ouédraogo de Ouagadougou, Ouagadougou, Burkina Faso
  36. 36 Institut Hédi-Raïs d’Ophtalmologie de Tunis, Faculté de Médecine de Tunis, Université Tunis El Manar, Tunis, Tunisia
  37. 37 Etablissement Hospitalière Spécialise Emir Abdelkader CEA Service d’Oncologie Pédiatrique, Oran, Algeria
  38. 38 Cliniques Universitaires Saint-Luc, Brussel, Belgium
  39. 39 Our Lady’s Children’s Hospital, Dublin, Ireland
  40. 40 Centro Hospital Universitário de Coimbra, University of Coimbra, Coimbra, Portugal
  41. 41 Hospital Sant Joan de Déu, Barcelona, Spain
  42. 42 Eye Clinic, University Hospital ‘Alexandrovska’, Department of Ophthalmology, Medical University, Sofia, Bulgaria
  43. 43 Muhimbili National Hospital, Dar es Salaam, Tanzania
  44. 44 Department of Ophthalmology, The Children’s Memorial Health Institute, Warsaw, Poland
  45. 45 Oncology Institute ‘Prof. Dr. Al. Trestioreanu’ Bucharest, Romania
  46. 46 Semmelweis University Budapest, Budapest, Hungary
  47. 47 Quelimane central Hospital, Quelimane, Mozambique
  48. 48 Red Cross Children’s War Memorial Hospital and the University of Cape Town, Cape Town, South Africa
  49. 49 Institut curie, Paris, France
  50. 50 University of KwaZulu-Natal, Durban, South Africa
  51. 51 Children’s Cancer Hospital Egypt 57357, Cairo, Egypt
  52. 52 Oncology Department, National Cancer Institute, University of Gezira, Wadi Madani, Sudan
  53. 53 Ophthalmology Unit, Department of Surgery, School of Medicine and Dentistry, University of Ghana, Accra, Ghana
  54. 54 Magrabi ICO Cameroon Eye Institute, Yaounde, Cameroon
  55. 55 Department of Ophthalmology, University College Hospital/University of Ibadan, Ibadan, Oyo State, Nigeria
  56. 56 Hospital Universitario Virgen Macarena, Sevilla, Spain
  57. 57 Lions Sight First Eye Hospital, Queen Elizabeth Central Hospital, Blantyre, Malawi
  58. 58 Servicio Andaluz de Salud (SAS), Sevilla, Spain
  59. 59 Charlotte Maxeke Johannesburg Academic Hospital, Johannesburg, South Africa
  60. 60 Addis Ababa University, School of Medicine, Department of Ophthalmology, Addis Ababa, Ethiopia
  61. 61 Department of Clinical Genetics, and Center for Rare Disorders, Aarhus University Hopspital, Aarhus, Denmark
  62. 62 Département de Pédiatrie, CHU Sylvanus Olympio, Université de Lomé, Lomé, Togo
  63. 63 Retinoblastoma referral center, University of Siena, Siena, Italy
  64. 64 University Childrens’ Hospital, Bratislava, Slovakia
  65. 65 Pediatric Hematology and Oncology Department of Rabat – Mohammed V University, Rabat, Morocco
  66. 66 Department of Pediatrics and Child Health, Jimma University Medical Center, Jimma, Ethiopia
  67. 67 Department of Ophthalmology, Oslo University Hospital, Oslo, Norway
  68. 68 Institute for Oncology and Radiology, Belgrade, Serbia
  69. 69 Birmingham Children’s Hospital Eye Department, Birmingham Women’s and Children’s NHS Foundation Trust, Birmingham, UK
  70. 70 Bukavu Eye Clinic – Bukavu Official University, Bukavu, DRC
  71. 71 Makerere University College of Health Sciences, Department of Ophthalmology, Kamplala, Uganda
  72. 72 Ophthalmology Department, Central Children’s Hospital of Georgia, Tbilisi, Georgia
  73. 73 University Hospital Brno, Masaryk University and ICRC/St. Anna University Hospital, Brno, Czech Republic
  74. 74 East Tallinn Central Hospital, Tallinn, Estonia
  75. 75 Oncologue Pédiatre Responsable d’Unité de Bangui, Bangui, Central African Republic
  76. 76 Chidren’s Ophthalmology Department, Chidren’s Hospital of Vilnius, University Hospital Santaros Clinic, Vilnius, Lithuania
  77. 77 Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Stellenbosch, South Africa
  78. 78 University Hospital Hamburg-Eppendorf, Hamburg, Germany
  79. 79 Clinical Center Of Vojvodina – University Eye Clinic, Eye Research Foundation Vidar – Latinović, Novi Sad, Serbia
  80. 80 Division of Ophthalmology, University of Cape Town, Cape Town, South Africa
  81. 81 University Clinics of Lubumbashi, University of Lubumbashi, Lubumbashi, DRC
  82. 82 The Okhmatdyt National Children’s Hospital, Kiev, Ukraine
  83. 83 Sekuru Kaguvi Eye Unit, Parirenyatwa Group of Hospitals, Harare, Zimbabwe
  84. 84 Ruharo Eye Hospital, Mbarara, Uganda
  85. 85 Botswana Government – Scottish Livingstone Hospital, Molepolole, Botswana
  86. 86 Department of Ophthalmology, Jimma University, Jimma, Ethiopia
  87. 87 Department of Ophthalmology, University of Padova, Padova, Italy
  88. 88 Kilimanjaro Christian Medical Center, Moshi, Tanzania
  89. 89 Pathology Department, Faculty of Medicine, University of Gezira, Wadi Madani, Sudan
  90. 90 Department of Ophthalmology, Amsterdam UMC, Amsterdam, Netherlands
  91. 91 Service d’oncologie pédiatrique de l’hôpital Aristide le Dantec, Dakar, Senegal
  92. 92 Ministry of Health, Lusaka, Zambia
  93. 93 Department of Ophthalmology, Lagos University Teaching Hospital/College of Medicine of the University of Lagos, Lagos, Nigeria
  94. 94 Abii Specialists Hospital, Bamenda, Cameroon
  95. 95 N.N. Alexandrov National Cancer Center of Belarus, Minsk, Belarus
  96. 96 Cheikh Anta DIOP University of Dakar, Le Dantec Hospital, Dakar, Senegal
  97. 97 Moscow Helmholtz Research Institute of Eye Diseases, Moscow, Russia
  98. 98 Calabar Children’s Eye Center, Department of Ophthalmology University of Calabar Teaching Hospital Calabar Cross River State, Nigeria
  99. 99 Arthur Davison Children’s Hospital, Ndola, Zambia
  100. 100 Chu Angondje Cancerologie, Libreville, Gabon
  101. 101 Komfo Anokye Teaching Hospital, Kumasi, Ghana
  102. 102 National Ophthalmological Institute of Angola, Luanda, Angola
  103. 103 Yerevan State Medical University, Department of Oncology and Pediatric Cancer and Blood Disorders Center of Armenia, Hematology Center after R.H. Yeolyan, Yerevan, Armenia
  104. 104 University Hospital Center Zagreb, Zagreb, Croatia
  105. 105 Center Hospitaliere Universitaire de Kamenge, Bujumbura, Burundi
  106. 106 Department of Ophthalmology for Children and Adults, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague, Czech Republic
  107. 107 Head and Neck Tumors Department, SRI of Pediatric Oncology and Hematology of N.N. Blokhin National Medical Research Center of Oncology of Russian Federation, Moscow, Russian Federation
  108. 108 Medical Academy of Postgraduate Education, Moscow, Russia
  109. 109 Univ. Medical Center Ljubljana, Univ.Eye Hospital Ljubljana, Ljubljana, Slovenia
  110. 110 Good Shepherd Hospital, Siteki, Swaziland
  111. 111 Center Hospitalier Universitaire Joseph Ravoahangy Andrianavalona, Antananarivo, Madagascar
  112. 112 University of Ghana School of Medicine and Dentistry, Korle Bu Teaching Hospital, Accra, Ghana
  113. 113 University of Pretoria, Pretoria, South Africa
  114. 114 Federal Medical Center, Yola, Nigeria
  115. 115 Nampula central hospital, Nampula, Mozambique
  116. 116 Department of Pediatrics and Adolescent Medicine, Division of Pediatric Hematology/Oncology, Medical University of Graz, Graz, Austria
  117. 117 Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
  118. 118 Pediatric Hemato-Oncology, Hospital Universitario Infantil La Paz, Madrid, Spain
  119. 119 Ophthalmology department, Nouakchott Medical University, Nouakchott, Mauritania
  120. 120 Mulago National Referral and Teaching Hospital, Kamplala, Uganda
  121. 121 Department of Paediatrics and Child Health, University of the Free Sate, Bloemfontein, South Africa
  122. 122 Department of Pediatric Hematology and Oncology, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague, Czech Republic
  123. 123 Africa Institute of Tropical Ophtalmology, Bamako, Mali
  124. 124 University Eye Clinic, Skopje, Macedonia
  125. 125 Kabgayi Eye Unit, Gitarama, Rwanda
  126. 126 Pediatric Oncology Service, Gabriel Toure Hospital, Bamako, Mali
  127. 127 Université Adam Barka, Adam Barka, Chad
  128. 128 Department of ophthalmology, Aarhus University Hospital, Aarhus, Denmark
  129. 129 Children’s Clinical University Hospital, Riga, Latvia
  130. 130 Department of Ophthalmology, Medical University Graz, Graz, Austria
  131. 131 Jos University Teaching Hospital, Jos, Nigeria
  132. 132 National Eye Center Kaduna, Kaduna, Nigeria
  133. 133 Service d’Ophtalmologie, Cliniques Universitaires de Kinshasa, Université de Kinshasa, Kinshasa, DRC
  134. 134 S.Fyodorov Eye Microsurgery Federal State Institution, Moscow, Russia
  135. 135 Assistante Hospitalo – Universitaire, Faculte de Medecine de Nouakchott Medecin Oncopediatre, Center National d’Oncologie, Nouakchott, Mauritania
  136. 136 Radiology Department, Sheba Medical Center, Ramat-Gan, Israel
  137. 137 Ophthalmology Department, Great Ormond Street Children’s Hospital, London, UK
  1. Correspondence to Ido Didi Fabian, International Centre for Eye Helath, London School of Hygiene and Tropical Medicine, London, UK and The Goldschleger Eye Institute, Sheba Medical Center, Tel Hashomer, Tel-Aviv University, Tel-Aviv, Israel didi{at}didifabian.com

Abstract

Background The travel distance from home to a treatment centre, which may impact the stage at diagnosis, has not been investigated for retinoblastoma, the most common childhood eye cancer. We aimed to investigate the travel burden and its impact on clinical presentation in a large sample of patients with retinoblastoma from Africa and Europe.

Methods A cross-sectional analysis including 518 treatment-naïve patients with retinoblastoma residing in 40 European countries and 1024 treatment-naïve patients with retinoblastoma residing in 43 African countries.

Results Capture rate was 42.2% of expected patients from Africa and 108.8% from Europe. African patients were older (95% CI −12.4 to −5.4, p<0.001), had fewer cases of familial retinoblastoma (95% CI 2.0 to 5.3, p<0.001) and presented with more advanced disease (95% CI 6.0 to 9.8, p<0.001); 43.4% and 15.4% of Africans had extraocular retinoblastoma and distant metastasis at the time of diagnosis, respectively, compared to 2.9% and 1.0% of the Europeans. To reach a retinoblastoma centre, European patients travelled 421.8 km compared to Africans who travelled 185.7 km (p<0.001). On regression analysis, lower-national income level, African residence and older age (p<0.001), but not travel distance (p=0.19), were risk factors for advanced disease.

Conclusions Fewer than half the expected number of patients with retinoblastoma presented to African referral centres in 2017, suggesting poor awareness or other barriers to access. Despite the relatively shorter distance travelled by African patients, they presented with later-stage disease. Health education about retinoblastoma is needed for carers and health workers in Africa in order to increase capture rate and promote early referral.

  • Epidemiology
  • Neoplasia
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Footnotes

  • Contributors Conception and design: IDF, AF, RB. Administrative support: CB, MZ. Collection and assembly of data: all authors. Data analysis and interpretation: IDF, NC, AF, TTK, FLM, MAR, MSS, ASS. Statistical analysis: AWS. Manuscript drafting: IDF, AF, AWS, RB. Critical revision of the manuscript for important intellectual content: all authors. Final approval of manuscript: all authors. Accountable for all aspects of the work: all authors.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Ethics approval The study was approved by the Institutional Review Board of the London School of Hygiene & Tropical Medicine (reference number 14574).

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data are available in a public, open-access repository.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.

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