{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T13:24:47Z","timestamp":1792416287013,"version":"4.4.0"},"reference-count":15,"publisher":"BMJ","issue":"11","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2015,11,10]]},"published-print":{"date-parts":[[2015,11]]},"abstract":"\n Objectives<\/jats:title>\n We aimed to design and test a method to extract information on antithrombotic therapy from anonymised free-text notes in the Clinical Practice Research Datalink (CPRD).<\/jats:p>\n <\/jats:sec>\n \n Setting<\/jats:title>\n General practice database representative of the UK.<\/jats:p>\n <\/jats:sec>\n \n Participants<\/jats:title>\n All patients undergoing total hip replacement (THR, n=25\u2005898) or total knee replacement (TKR, n=22\u2005231) between January 2008 and October 2012 were included. Antithrombotic drug use related to THR or TKR was identified using anonymised free text and prescription data.<\/jats:p>\n <\/jats:sec>\n \n Primary and secondary outcome measures<\/jats:title>\n Internal validity of our newly designed method was determined by calculating positive predictive values (PPVs) of hits for predefined keywords in a random sample of anonymised free-text notes. In order to determine potential detection bias, total joint replacement (TJR) patient characteristics were compared as per their status of exposure to antithrombotics.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n PPVs ranging between 97% and 99% for new oral anticoagulants (NOAC) or low-molecular weight heparins (LMWH) exposure related to TJR were obtained with our method. Our search strategy increased detection rates by 57%, yielding a total proportion of 18.5% of all THR and 18.6% of all TKR surgeries. Identified users of NOACs and LMWHs were largely similar with regards to age, sex, lifestyle, disease and drug history compared to patients without identified drug use.<\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n We have developed a useful method to identify additional exposure to NOACs or LMWHs with TJR surgery.<\/jats:p>\n <\/jats:sec>","DOI":"10.1136\/bmjopen-2015-009017","type":"journal-article","created":{"date-parts":[[2015,11,30]],"date-time":"2015-11-30T22:09:58Z","timestamp":1448921398000},"page":"e009017","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":3,"title":["Identification of antithrombotic drugs related to total joint replacement using anonymised free-text notes: a search strategy in the Clinical Practice Research Datalink"],"prefix":"10.1136","volume":"5","author":[{"given":"Johannes TH","family":"Nielen","sequence":"first","affiliation":[{"name":"Division of Pharmacoepidemiology & Clinical Pharmacology, Utrecht University, Utrecht, The Netherlands"},{"name":"Department of Epidemiology, CAPHRI School for Public Health and Primary Care, Maastricht University, Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bart J F","family":"van den Bemt","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Sint Maartenskliniek, Nijmegen, The Netherlands"},{"name":"Department of Pharmacy, Radboud University Medical Center, Nijmegen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annelies","family":"Boonen","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Division of Rheumatology, Maastricht University Medical Centre, Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pieter C","family":"Dagnelie","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, CAPHRI School for Public Health and Primary Care, and CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pieter J","family":"Emans","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, Maastricht University Medical Center, Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicole","family":"Veldhorst","sequence":"additional","affiliation":[{"name":"Department of Clinical Pharmacy and Toxicology, Maastricht University Medical Center, Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arief","family":"Lalmohamed","sequence":"additional","affiliation":[{"name":"Department of Clinical Pharmacy, University Medical Center Utrecht, Utrecht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tjeerd-Pieter","family":"van Staa","sequence":"additional","affiliation":[{"name":"Division of Pharmacoepidemiology & Clinical Pharmacology, Utrecht University, Utrecht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frank","family":"de Vries","sequence":"additional","affiliation":[{"name":"Division of Pharmacoepidemiology & Clinical Pharmacology, Utrecht University, Utrecht, The Netherlands"},{"name":"Department of Clinical Pharmacy and Toxicology, Maastricht University Medical Center, Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2015,11,30]]},"reference":[{"key":"2025121509093880000_5.11.e009017.1","unstructured":"Arthritis Research UK. Osteoarthritis in general practice. 2013:1\u201336. http:\/\/www.arthritisresearchuk.org\/arthritis-information\/data-and-statistics\/osteoarthritis.aspx (accessed 9 Feb 2015)."},{"key":"2025121509093880000_5.11.e009017.2","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(07)60457-7"},{"key":"2025121509093880000_5.11.e009017.3","doi-asserted-by":"crossref","first-page":"642","DOI":"10.1111\/jth.12158","article-title":"Prolonged outpatient vitamin K antagonist use and risk of venous thromboembolism in patients undergoing total hip or knee replacement","volume":"11","author":"Lalmohamed","year":"2013","journal-title":"J Thromb Haemost"},{"key":"2025121509093880000_5.11.e009017.4","doi-asserted-by":"publisher","DOI":"10.1378\/chest.11-2404"},{"key":"2025121509093880000_5.11.e009017.5","doi-asserted-by":"crossref","first-page":"654","DOI":"10.1160\/TH03-02-0086","article-title":"Optimal low-molecular-weight heparin regimen in major orthopedic surgery: a meta-analysis of randomised trials","volume":"90","author":"Zufferey","year":"2003","journal-title":"Thromb Haemost"},{"key":"2025121509093880000_5.11.e009017.6","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(11)61514-6"},{"key":"2025121509093880000_5.11.e009017.7","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMra044440"},{"key":"2025121509093880000_5.11.e009017.8","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.e3675"},{"key":"2025121509093880000_5.11.e009017.9","doi-asserted-by":"crossref","first-page":"584","DOI":"10.1160\/TH11-11-0784","article-title":"Net clinical benefit of new oral anticoagulants (dabigatran, rivaroxaban, apixaban) versus no treatment in a \u2018real world\u2019 atrial fibrillation population: a modelling analysis based on a nationwide cohort study","volume":"107","author":"Banerjee","year":"2012","journal-title":"Thromb Haemost"},{"key":"2025121509093880000_5.11.e009017.10","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijcard.2014.11.182"},{"key":"2025121509093880000_5.11.e009017.11","doi-asserted-by":"publisher","DOI":"10.1002\/pds.1151"},{"key":"2025121509093880000_5.11.e009017.12","doi-asserted-by":"publisher","DOI":"10.1177\/2042098611435911"},{"key":"2025121509093880000_5.11.e009017.13","doi-asserted-by":"crossref","first-page":"e65891","DOI":"10.1371\/journal.pone.0065891","article-title":"Patterns of risk of cancer in patients with metal-on-metal hip replacements versus other bearing surface types: a record linkage study between a prospective joint registry and general practice electronic health records in England","volume":"8","author":"Lalmohamed","year":"2013","journal-title":"PLoS ONE"},{"key":"2025121509093880000_5.11.e009017.14","doi-asserted-by":"crossref","first-page":"918","DOI":"10.1016\/j.joca.2014.04.013","article-title":"The effect of body mass index on the risk of post-operative complications during the 6 months following total hip replacement or total knee replacement surgery","volume":"22","author":"Wallace","year":"2014","journal-title":"Osteoarthritis Cartil"},{"key":"2025121509093880000_5.11.e009017.15","unstructured":"Hospital Episode Statistics. Admitted Patient Care\u2014England, 2008\u20132013. http:\/\/www.hscic.gov.uk\/ (accessed 9 Nov 2014)."}],"container-title":["BMJ Open"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bmjopen-2015-009017","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,15]],"date-time":"2025-12-15T17:09:43Z","timestamp":1765818583000},"score":1,"resource":{"primary":{"URL":"https:\/\/bmjopen.bmj.com\/lookup\/doi\/10.1136\/bmjopen-2015-009017"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,11]]},"references-count":15,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2015,11,30]]},"published-print":{"date-parts":[[2015,11]]}},"alternative-id":["10.1136\/bmjopen-2015-009017"],"URL":"https:\/\/doi.org\/10.1136\/bmjopen-2015-009017","relation":{},"ISSN":["2044-6055","2044-6055"],"issn-type":[{"value":"2044-6055","type":"print"},{"value":"2044-6055","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,11]]}}}