{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,4]],"date-time":"2026-11-04T12:10:49Z","timestamp":1793794249620,"version":"4.6.1"},"reference-count":53,"publisher":"Georg Thieme Verlag KG","issue":"06","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Semin Thromb Hemost"],"published-print":{"date-parts":[[2023,9]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Mixing studies have long been in the clinical laboratory armamentarium for investigating unexpected, prolonged activated partial thromboplastin time (aPTT) or prothrombin time (PT). The purpose of the mixing study is to identify whether the aPTT\/PT prolongation is secondary to a factor deficiency versus an inhibitor, which would present as a \u201ccorrected\u201d and \u201cnoncorrected\u201d mixing study, respectively. The differentiation between a factor deficiency and inhibitor may likely further direct clinical decisions, including additional diagnostic testing or factor replacement therapy. While aPTT\/PT mixing studies are simple tests to perform, there is a lack of standardization for both the testing protocol and the interpretation of what is considered to be a corrected or noncorrected mixing study result. This review will describe the common indications for the mixing test, preanalytic variables that may affect mixing study performance, and describe several methods for interpreting the results of aPTT and PT mixing tests.<\/jats:p>","DOI":"10.1055\/s-0042-1756196","type":"journal-article","created":{"date-parts":[[2022,9,2]],"date-time":"2022-09-02T22:50:01Z","timestamp":1662159001000},"page":"571-579","source":"Crossref","is-referenced-by-count":23,"title":["Activated Partial Thromboplastin Time and Prothrombin Time Mixing Studies: Current State of the Art"],"prefix":"10.1055","volume":"49","author":[{"given":"Dorothy M.","family":"Adcock","sequence":"additional","affiliation":[{"name":"Laboratory Corporation of America, Burlington, North Carolina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gary W.","family":"Moore","sequence":"additional","affiliation":[{"name":"Specialist Haemostasis Unit, Department of Haematology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom"},{"name":"Department of Natural Sciences, Middlesex University London, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silmara de Lima","family":"Montalv\u00e3o","sequence":"additional","affiliation":[{"name":"Laboratory Hemostasis, Hematology and Hemotherapy Center, University of Campinas (UNICAMP), Campinas-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geoffrey","family":"Kershaw","sequence":"additional","affiliation":[{"name":"Institute of Haematology, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert C.","family":"Gosselin","sequence":"additional","affiliation":[{"name":"Davis Health System, Hemostasis and Thrombosis Center, University of California, Sacramento, California"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2022,9,2]]},"reference":[{"issue":"05","key":"ref1","first-page":"285","article-title":"Laboratory evaluation of prolonged APTT and PT","volume":"35","author":"M Bethel","year":"2004","journal-title":"Lab Med"},{"issue":"04","key":"ref2","doi-asserted-by":"crossref","first-page":"749","DOI":"10.1002\/rth2.12252","article-title":"Prolonged APTT of unknown etiology: a systematic evaluation of causes and laboratory resource use in an outpatient hemostasis academic unit","volume":"3","author":"A CN Barbosa","year":"2019","journal-title":"Res Pract Thromb Haemost"},{"key":"ref3","doi-asserted-by":"crossref","DOI":"10.1007\/978-3-319-30726-8_1","volume-title":"Screening coagulation assays, factor XIII and D-dimer","author":"D M Adcock","year":"2016"},{"issue":"20","key":"ref4","doi-asserted-by":"crossref","first-page":"2146","DOI":"10.1001\/jama.2016.15749","article-title":"Mixing study for the evaluation of abnormal coagulation test","volume":"316","author":"S H Choi","year":"2016","journal-title":"JAMA"},{"issue":"01","key":"ref5","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1002\/ajh.25669","article-title":"Coagulation mixing studies: utility, algorithmic strategies and limitations for lupus anticoagulant testing or follow up of abnormal coagulation tests","volume":"95","author":"E J Favaloro","year":"2020","journal-title":"Am J Hematol"},{"issue":"01","key":"ref7","first-page":"1593","article-title":"An international study of how laboratories handle and evaluate patient samples after detecting an unexpected APTT prolongation","volume":"53","author":"E Azner","year":"2015","journal-title":"Clin Chem Lab Med"},{"issue":"05","key":"ref8","doi-asserted-by":"crossref","first-page":"504","DOI":"10.1080\/00313020701569998","article-title":"Mis-identification of factor inhibitors by diagnostic haemostasis laboratories: recognition of pitfalls and elucidation of strategies. 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