{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T13:55:06Z","timestamp":1792677306431,"version":"4.5.0"},"reference-count":38,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2022,7,19]],"date-time":"2022-07-19T00:00:00Z","timestamp":1658188800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2022,7,19]],"date-time":"2022-07-19T00:00:00Z","timestamp":1658188800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Universit\u00e4tsklinikum Augsburg"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Eur J Trauma Emerg Surg"],"published-print":{"date-parts":[[2023,2]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Purpose<\/jats:title>\n                <jats:p>The aim of our study was to investigate the use of tranexamic acid in patients with proximal femoral fractures and compare the total blood loss, transfusion rates, complications, and the application method.\n<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>A retrospective single center cohort study (level I trauma center) with 1479 patients treated operatively for a proximal femoral fracture between January 2016 and June 2020 was performed. 1\u00a0g of tranexamic acid was applied (systemic, topic or combined application). Patient data, surgical procedure, complications, and mortality were assessed. Hemoglobin levels, blood loss and transfusion rates for patients with and without tranexamic acid and the application methods were compared.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>667 femoral neck fractures, 701 pertrochanteric and 109 subtrochanteric fractures were included. Mean age was 80.8\u00a0years. 274 patients received tranexamic acid. At admission average hemoglobin was 12.2\u00a0g\/l. Hemoglobin drop postoperatively was less after tranexamic acid (9.72 vs. 9.35\u00a0g\/dl). Transfusion rates were lowered significantly by 17.1% after tranexamic acid. Blood loss was reduced for all patients after tranexamic acid independent of fracture morphology. The combination of 1\u00a0g i.v. and 1\u00a0g topical-applied tranexamic acid seems to be more effective. Complication rates did not differ.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusion<\/jats:title>\n                <jats:p>Tranexamic acid is effective in reducing blood loss and transfusion rates, without increasing the risk of thromboembolic events after proximal femoral fractures. For open reduction and nailing and arthroplasty in fracture setting combined topical and single i.v. application seems most effective and closed reduction with nailing can be treated by single dose i.v. application of 1\u00a0g tranexamic acid.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s00068-022-02042-6","type":"journal-article","created":{"date-parts":[[2022,7,19]],"date-time":"2022-07-19T11:06:52Z","timestamp":1658228812000},"page":"209-216","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Does tranexamic acid reliably reduce blood loss in proximal femur fracture surgery?"],"prefix":"10.1007","volume":"49","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1976-3326","authenticated-orcid":false,"given":"A.","family":"Fenwick","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"I.","family":"Antonovska","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M.","family":"Pfann","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J.","family":"Mayr","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A.","family":"Wiedl","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S.","family":"Nuber","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S.","family":"F\u00f6rch","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"E.","family":"Mayr","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2022,7,19]]},"reference":[{"issue":"1 Suppl","key":"2042_CR1","doi-asserted-by":"publisher","first-page":"57","DOI":"10.1016\/8756-3282(95)00381-9","volume":"18","author":"P Kannus","year":"1996","unstructured":"Kannus P, Parkkari J, Sievanen H, et al. Epidemiology of hip fractures. Bone. 1996;18(1 Suppl):57\u201363.","journal-title":"Bone"},{"issue":"3 Suppl","key":"2042_CR2","doi-asserted-by":"publisher","first-page":"121S","DOI":"10.1016\/8756-3282(95)00492-0","volume":"18","author":"LJ Melton 3rd","year":"1996","unstructured":"Melton LJ 3rd. Epidemiology of hip fractures: implications of the exponential increase with age. Bone. 1996;18(3 Suppl):121S-125S. https:\/\/doi.org\/10.1016\/8756-3282(95)00492-0.","journal-title":"Bone"},{"key":"2042_CR3","doi-asserted-by":"publisher","first-page":"665","DOI":"10.3238\/arztebl.m2021.0238","volume":"118","author":"M Rupp","year":"2021","unstructured":"Rupp M, Walter N, Pfeifer C, Lang S, Kerschbaum M, Krutsch W, Baumann F, Alt V. The incidence of fractures among the adult population of Germany\u2014an analysis from 2009 through 2019. Dtsch Arztebl Int. 2021;118:665\u20139. https:\/\/doi.org\/10.3238\/arztebl.m2021.0238.","journal-title":"Dtsch Arztebl Int"},{"key":"2042_CR4","volume-title":"Campbell\u2019s operative orthopaedics","author":"ST Canale","year":"2007","unstructured":"Canale ST, Beaty JH. Campbell\u2019s operative orthopaedics. 11th ed. Mosby: Elsevier Masson; 2007.","edition":"11"},{"issue":"7","key":"2042_CR5","doi-asserted-by":"publisher","first-page":"1100","DOI":"10.1016\/j.arth.2010.11.013","volume":"26","author":"X Liu","year":"2011","unstructured":"Liu X, Zhang X, et al. Hidden blood loss after total hip arthroplasty. J Arthoplasty. 2011;26(7):1100-5.e1. https:\/\/doi.org\/10.1016\/j.arth.2010.11.013.","journal-title":"J Arthoplasty"},{"key":"2042_CR6","doi-asserted-by":"publisher","first-page":"36","DOI":"10.1186\/s13018-015-0185-9","volume":"10","author":"K Miao","year":"2015","unstructured":"Miao K, Ni S, et al. Hidden blood loss and its influential factors after total hip arthroplasty. J Orthop Surg Res. 2015;10:36.","journal-title":"J Orthop Surg Res"},{"key":"2042_CR7","doi-asserted-by":"publisher","first-page":"1053","DOI":"10.1302\/0301-620X.88B8.17534","volume":"88-B","author":"NB Foss","year":"2006","unstructured":"Foss NB, Kehlet H. Hidden blood loss after surgery for hip fracture. J Bone Joint Surg [Br]. 2006;88-B:1053\u20139.","journal-title":"J Bone Joint Surg [Br]"},{"key":"2042_CR8","doi-asserted-by":"publisher","first-page":"1717","DOI":"10.1046\/j.0041-1132.2003.00581.x","volume":"43","author":"VA Lawrence","year":"2003","unstructured":"Lawrence VA, Silverstein JH, Cornell JE, et al. Higher Hb level is associated with better early functional recovery after hip fracture repair. Transfusion. 2003;43:1717\u201322.","journal-title":"Transfusion"},{"issue":"2","key":"2042_CR9","doi-asserted-by":"publisher","first-page":"p173","DOI":"10.1093\/ageing\/afm161","volume":"37","author":"NB Foss","year":"2008","unstructured":"Foss NB, Kristensen MT, Kehlet H. Anaemia impedes functional mobility after hip fracture surgery. Age Ageing. 2008;37(2):p173-178.","journal-title":"Age Ageing"},{"issue":"6","key":"2042_CR10","doi-asserted-by":"publisher","first-page":"369","DOI":"10.1097\/00005131-200407000-00007","volume":"18","author":"EA Halm","year":"2004","unstructured":"Halm EA, Wang JJ, Boockvar K, et al. The effect of perioperative anemia on clinical and functional outcomes in patients with hip fracture. J Orthop Trauma. 2004;18(6):369\u201374.","journal-title":"J Orthop Trauma"},{"key":"2042_CR11","doi-asserted-by":"publisher","first-page":"167","DOI":"10.1016\/j.injury.2010.07.239","volume":"42","author":"D Kumar","year":"2011","unstructured":"Kumar D, Mbako AN, Riddick A, Patil S, Williams P. On admission haemoglobin in patients with hip fracture. Injury. 2011;42:167\u201370.","journal-title":"Injury"},{"issue":"Suppl 14","key":"2042_CR12","doi-asserted-by":"publisher","first-page":"41","DOI":"10.1136\/jcp.33.Suppl_14.41","volume":"33","author":"IM Nilsson","year":"1980","unstructured":"Nilsson IM. Clinical pharmacology of aminocaproic and tranexamic acids. J Clin Pathol. 1980;33(Suppl 14):41\u20137.","journal-title":"J Clin Pathol"},{"key":"2042_CR13","doi-asserted-by":"publisher","first-page":"23","DOI":"10.1016\/S0140-6736(10)60835-5","volume":"376","author":"H Shakur","year":"2010","unstructured":"CRASH-2 trial collaborator, Shakur H, Roberts I, et al. Effects of tranexamic acid o death, vascular occlusive events, and blood transfusion in trauma patients with significant haemorrhage (CRASH-2): a randomized, placebo-controlled trial. Lancet. 2010;376:23\u201332.","journal-title":"Lancet"},{"key":"2042_CR14","doi-asserted-by":"publisher","first-page":"1577","DOI":"10.1302\/0301-620X.93B12.26989","volume":"93","author":"S Alshryda","year":"2011","unstructured":"Alshryda S, Sarda P, Sukeik M, et al. Tranexamic acid in total knee replacement: a systematic review and meta-analysis. J Bone Jt Surg Br. 2011;93:1577\u201385.","journal-title":"J Bone Jt Surg Br"},{"key":"2042_CR15","doi-asserted-by":"publisher","first-page":"1005","DOI":"10.1302\/0301-620X.96B8.33745","volume":"96-B","author":"S Alshryda","year":"2014","unstructured":"Alshryda S, Sukeik M, Sarda P, et al. A systematic review and meta-analysis of the topical administration of tranexamic acid in total hip and knee replacement. Bone Jt J. 2014;96-B:1005\u201315.","journal-title":"Bone Jt J"},{"key":"2042_CR16","doi-asserted-by":"publisher","first-page":"752","DOI":"10.1016\/j.spinee.2015.01.013","volume":"15","author":"T Cheriyan","year":"2015","unstructured":"Cheriyan T, Maier SP 2nd, Bianco K, Slobodyanyuk K, Rattenni RN, Lafage V, Schwab FJ, Lonner BS, Errico TJ. Efficacy of tranexamic acid on surgical bleeding in spine surgery: a meta-analysis. Spine J. 2015;15:752\u201361.","journal-title":"Spine J"},{"issue":"1","key":"2042_CR17","doi-asserted-by":"publisher","first-page":"91","DOI":"10.1111\/j.1471-0528.2008.01926.x","volume":"116","author":"A Sundstr\u00f6m","year":"2009","unstructured":"Sundstr\u00f6m A, Seaman H, Kieler H, Alfredsson L. The risk of venous thromboembolism associated with the use of tranexamic acid and other drugs used to treat menorrhagia: a case-control study using the general practice research database. BJOG. 2009;116(1):91\u20137.","journal-title":"BJOG"},{"key":"2042_CR18","doi-asserted-by":"publisher","first-page":"345","DOI":"10.1097\/BOT.0000000000000837","volume":"31","author":"CD Watts","year":"2017","unstructured":"Watts CD, Houdek MT, et al. Tranexamic acid safely reduced blood loss in hemi- and total hip arthroplasty for acute femoral neck fracture: a randomized clinical trial. J Orthop Trauma. 2017;31:345\u201351.","journal-title":"J Orthop Trauma"},{"key":"2042_CR19","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1177\/21514593211063668","volume":"12","author":"PAN Huynh","year":"2021","unstructured":"Huynh PAN, Miller M, Will R. Intravenous tranexamic acid decreases blood transfusions and blood loss for patients with surgically treated hip fractures. Geriatr Orthop Surg Rehabil. 2021;12:1\u20135. https:\/\/doi.org\/10.1177\/21514593211063668.","journal-title":"Geriatr Orthop Surg Rehabil"},{"issue":"1","key":"2042_CR20","doi-asserted-by":"publisher","first-page":"23","DOI":"10.1093\/bja\/aep314","volume":"104","author":"PJ Zufferey","year":"2010","unstructured":"Zufferey PJ, Miquet M, et al. Tranexamic acid in hip fracture surgery: a randomized controlled trial. Br J Anaesth. 2010;104(1):23\u201330. https:\/\/doi.org\/10.1093\/bja\/aep314.","journal-title":"Br J Anaesth"},{"key":"2042_CR21","doi-asserted-by":"publisher","first-page":"747","DOI":"10.1302\/0301-620X.98B6.36645","volume":"98-B","author":"PT Tengberg","year":"2016","unstructured":"Tengberg PT, Foss NB, et al. Tranexamic acid reduces blood loss in patients with extracapsular fractures of the hip. Bone Jt J. 2016;98-B:747\u201353.","journal-title":"Bone Jt J"},{"issue":"10","key":"2042_CR22","doi-asserted-by":"publisher","first-page":"e296","DOI":"10.1371\/journal.pmed.0040296","volume":"4","author":"E Von Elm","year":"2007","unstructured":"Von Elm E, Altman DG, Egger M, et al. The strengthening of the reporting of observational studies in epidemiology (strobe) statement: guidelines for reporting observational studies. Plos Med. 2007;4(10):e296. https:\/\/doi.org\/10.1371\/journal.pmed.0040296.","journal-title":"Plos Med"},{"issue":"5","key":"2042_CR23","doi-asserted-by":"publisher","first-page":"373","DOI":"10.1016\/0021-9681(87)90171-8","volume":"40","author":"ME Charlson","year":"1987","unstructured":"Charlson ME, Pompei P, Ales KL, MacKenzie CR. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis. 1987;40(5):373\u201383.","journal-title":"J Chronic Dis"},{"key":"2042_CR24","unstructured":"ASA Physical Classification System. American Society of Anesthesiologists. 2022. Available at  http:\/\/www.asahq.org\/Home\/For-Members\/Clincal-Information\/ASA-Physical-Status-Classification-System\/"},{"issue":"8","key":"2042_CR25","doi-asserted-by":"publisher","first-page":"465","DOI":"10.1185\/03007999609115227","volume":"13","author":"F Mercuriali","year":"1996","unstructured":"Mercuriali F, Inghilleri G. Proposal of an algorithm to help the choice of the best transfusion strategy. Curr Med Res Opin. 1996;13(8):465\u201378. https:\/\/doi.org\/10.1185\/03007999609115227 (Accepted 11 Sep 1996, Published online: 12 Aug 2008).","journal-title":"Curr Med Res Opin"},{"issue":"2","key":"2042_CR26","first-page":"224","volume":"51","author":"SB Nadler","year":"1962","unstructured":"Nadler SB, Hidalgo JH. Prediction of blood volume in normal human adults. Surgery. 1962;51(2):224\u201332 (Ted Bloch PMID: 21936146).","journal-title":"Surgery"},{"issue":"12","key":"2042_CR27","first-page":"378","volume":"30","author":"J Geddes","year":"2020","unstructured":"Geddes J, McConaghie G. Does perioperative use of tranexamic acid in hip fracture patients increase the risk of venous thromboembolism and reduce the need for postoperative transfusions? J Perioper Pract. 2020;30(12):378\u201382.","journal-title":"J Perioper Pract"},{"issue":"1","key":"2042_CR28","doi-asserted-by":"publisher","first-page":"3","DOI":"10.5301\/hipint.5000556","volume":"28","author":"D Baskaran","year":"2018","unstructured":"Baskaran D, Rahman S, et al. Effect of tranexamic acid use on blood loss and thromboembolic risk in hip fracture surgery: systematic review and meta-analysis. HIP Int. 2018;28(1):3\u201310.","journal-title":"HIP Int"},{"key":"2042_CR29","doi-asserted-by":"publisher","first-page":"635","DOI":"10.1111\/os.12511","volume":"11","author":"X Zhou","year":"2019","unstructured":"Zhou X, Zhang Y, et al. Efficacy and safety of tranexamic acid in intertrochanteric fractures: a single-blind randomized controlled trial. Orthop Surg. 2019;11:635\u201342. https:\/\/doi.org\/10.1111\/os.12511.","journal-title":"Orthop Surg"},{"issue":"8","key":"2042_CR30","doi-asserted-by":"publisher","first-page":"409","DOI":"10.1097\/BOT.0000000000000577","volume":"30","author":"A Drakos","year":"2016","unstructured":"Drakos A, Raoulis V, et al. Efficacy of local administration of tranexamic acid for blood salvage in patients undergoing intertrochanteric fracture surgery. J Orthop Trauma. 2016;30(8):409\u201314. https:\/\/doi.org\/10.1097\/BOT.0000000000000577.","journal-title":"J Orthop Trauma"},{"key":"2042_CR31","doi-asserted-by":"publisher","first-page":"124","DOI":"10.1186\/s13018-017-0625-9","volume":"12","author":"J Lei","year":"2017","unstructured":"Lei J, Zhang B, et al. Tranexamic acid reduces hidden blood loss in the treatment of intertrochanteric fractures with PFNA: a single-center randomized controlled trial. J Orthop Surg Res. 2017;12:124. https:\/\/doi.org\/10.1186\/s13018-017-0625-9.","journal-title":"J Orthop Surg Res"},{"key":"2042_CR32","doi-asserted-by":"publisher","first-page":"304","DOI":"10.1186\/s12891-019-2670-5","volume":"20","author":"J Xi","year":"2019","unstructured":"Xi J, Hu Q, et al. Efficacy and safety of tranexamic acid in geriatric hip fracture with hemiarthroplasty: a retrospective cohort study. BMC Musculoskelet Disord. 2019;20:304. https:\/\/doi.org\/10.1186\/s12891-019-2670-5.","journal-title":"BMC Musculoskelet Disord"},{"key":"2042_CR33","doi-asserted-by":"publisher","first-page":"117","DOI":"10.1016\/j.otsr.2019.10.015","volume":"106","author":"F Xing","year":"2020","unstructured":"Xing F, Chen W. Postoperative outcomes of tranexamic acid use in geriatric trauma patients treated with proximal femoral intramedullary nails: a systematic review and meta-analysis. Orthop Traumatol Surg Res. 2020;106:117\u201326.","journal-title":"Orthop Traumatol Surg Res"},{"key":"2042_CR34","doi-asserted-by":"publisher","first-page":"e024350","DOI":"10.1136\/bmjopen-2018-024350","volume":"9","author":"Q Sun","year":"2009","unstructured":"Sun Q, Li J, Chen J, et al. Comparison of intravenous, topical or combined routes of tranexamic acid administration in patients undergoing total knee and hip arthroplasty: a metaanalysis of randomized controlled trials. BMJ Open. 2009;9:e024350. https:\/\/doi.org\/10.1136\/bmjopen-2018-024350.","journal-title":"BMJ Open"},{"key":"2042_CR35","doi-asserted-by":"publisher","first-page":"997","DOI":"10.1007\/s00402-017-2683-1","volume":"137","author":"B Mi","year":"2017","unstructured":"Mi B, Liu G, et al. Intra-articular versus intravenous tranexamic acid application in total knee arthroplasty: a meta-analysis of randomized controlled trials. Arch Orthop Trauma Surg. 2017;137:997\u20131009. https:\/\/doi.org\/10.1007\/s00402-017-2683-1.","journal-title":"Arch Orthop Trauma Surg"},{"key":"2042_CR36","doi-asserted-by":"publisher","first-page":"1570","DOI":"10.1055\/s-0040-1710549","volume":"34","author":"A Abdallah","year":"2021","unstructured":"Abdallah A, Sallam A, et al. Topical tranexamic acid in total knee arthroplasty: does it augment the effect of intravenous administration in patients with moederate- to high-risk of bleeding? A randomized clinical trial. J Knee Surg. 2021;34:1570\u20138.","journal-title":"J Knee Surg"},{"key":"2042_CR37","doi-asserted-by":"publisher","first-page":"90","DOI":"10.1186\/s12891-017-1429-0","volume":"18","author":"P Zhang","year":"2017","unstructured":"Zhang P, Liang Y, et al. Combined application versus topical and intravenous application of tranexamic acid following primary total hip arthroplasty: a meta-analysis. BMC Musculoskelet Disord. 2017;18:90. https:\/\/doi.org\/10.1186\/s12891-017-1429-0.","journal-title":"BMC Musculoskelet Disord"},{"key":"2042_CR38","doi-asserted-by":"publisher","first-page":"1073","DOI":"10.1016\/j.otsr.2019.06.008","volume":"105","author":"L King","year":"2019","unstructured":"King L, Randle R, et al. Comparison of oral vs. combined topical\/intravenous\/oral tranexamic acid in the prevention of blood loss in total knee arthroplasty: a randomised clinical trial. Orthop Traumatol Surg Res. 2019;105:1073\u20137.","journal-title":"Orthop Traumatol Surg Res"}],"container-title":["European Journal of Trauma and Emergency Surgery"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00068-022-02042-6.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00068-022-02042-6\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00068-022-02042-6.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,2,14]],"date-time":"2023-02-14T01:22:48Z","timestamp":1676337768000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s00068-022-02042-6"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,7,19]]},"references-count":38,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2023,2]]}},"alternative-id":["2042"],"URL":"https:\/\/doi.org\/10.1007\/s00068-022-02042-6","relation":{},"ISSN":["1863-9933","1863-9941"],"issn-type":[{"value":"1863-9933","type":"print"},{"value":"1863-9941","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,7,19]]},"assertion":[{"value":"2 April 2022","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"30 June 2022","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"19 July 2022","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"All authors read and approved of the final manuscript. All authors believe this study represents honest work. All authors, their immediate families, and any research foundation with which they are affiliated with did not receive any financial payments or other benefits from any commercial entity related to the subject of this article. There has been no prior publication or submission. Annabel Fenwick, Iana Antonovska, Michael Pfann, Jakob Mayr, Andreas Wiedl, Stefan F\u00f6rch, Stefan Number and Edgar Mayr declare that they have no conflicts of interest.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}},{"value":"We declare that the study has been performed in accordance with the Declaration of Helsinki and has been approved by the ethical Committee of the University of Augsburg.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}}]}}