{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T18:07:22Z","timestamp":1777486042989,"version":"3.51.4"},"reference-count":43,"publisher":"Wiley","issue":"6","license":[{"start":{"date-parts":[[2020,12,28]],"date-time":"2020-12-28T00:00:00Z","timestamp":1609113600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":["ascpt.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Clin Pharma and Therapeutics"],"published-print":{"date-parts":[[2021,6]]},"abstract":"<jats:sec><jats:label\/><jats:p>Warfarin remains the oral anticoagulant of choice in sub\u2010Saharan Africa. However, dosing is challenging due to a highly variable clinical response for a given dose. This study aimed to develop and validate a clinical warfarin dose\u2010initiation model in sub\u2010Saharan Black\u2010African patients. For the development cohort, we used data from 364 patients who were recruited from 8 outpatient clinics and hospital departments in Uganda and South Africa (June 2018\u2013July 2019). Validation was undertaken using the International Warfarin Pharmacogenetics Consortium (IWPC) dataset (690 black patients). Four predictors (age, weight, target International Normalized Ratio range, and HIV status) were included in the final model, which achieved mean absolute errors (MAEs; mean of absolute differences between true dose and dose predicted by the model) of 11.6 (95% confidence interval (CI) 10.4\u201312.8) and 12.5 (95% CI 11.6\u201313.4) mg\/week in the development and validation cohorts, respectively. Two other clinical models, IWPC and Gage, respectively, obtained MAEs of 12.5 (95% CI 11.3\u201313.7) and 12.7 (95% CI 11.5\u201313.8) mg\/week in the development cohort, and 12.1 (95% CI 11.2\u201313.0) and 12.2 (95% CI 11.4\u201313.1) mg\/week in the validation cohort. Compared with fixed dose\u2010initiation, our model decreased the percentage of patients at high risk of suboptimal anticoagulation by 7.5% (1.5\u201313.7%) and 11.9% (7.1\u201316.8%) in the development and validation cohorts, respectively. The clinical utility of this model will be tested in a prospective study.<\/jats:p><\/jats:sec><jats:sec><jats:label\/><jats:p>\n<jats:boxed-text content-type=\"box\" position=\"anchor\"><jats:caption><jats:title>Study Highlights<\/jats:title><\/jats:caption><jats:p>\n<jats:list list-type=\"simple\">\n\n<jats:list-item><jats:p>\n<jats:bold>WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?<\/jats:bold>\n<\/jats:p><\/jats:list-item>\n<\/jats:list>\n<\/jats:p><jats:p>\u2611 Warfarin dosing remains challenging due to a highly variable clinical response for a given dose. \n<jats:list list-type=\"simple\">\n<jats:list-item><jats:p><jats:bold>WHAT QUESTION DID THIS STUDY ADDRESS?<\/jats:bold><\/jats:p><\/jats:list-item>\n<\/jats:list><\/jats:p><jats:p>\u2611 Can a clinical dose\u2010initiation model be developed and validated for sub\u2010Saharan Black\u2010African patients? \n<jats:list list-type=\"simple\">\n<jats:list-item><jats:p><jats:bold>WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?<\/jats:bold><\/jats:p><\/jats:list-item>\n<\/jats:list><\/jats:p><jats:p>\u2611 We have developed the first warfarin dose\u2010initiation clinical model for Black\u2010African patients in Uganda and South Africa. \n<jats:list list-type=\"simple\">\n<jats:list-item><jats:p><jats:bold>HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?<\/jats:bold><\/jats:p><\/jats:list-item>\n<\/jats:list><\/jats:p><jats:p>\u2611 We will be implementing and validating this model in a prospective cohort to inform future large\u2010scale implementation. More optimized dosing should improve the quality of warfarin anticoagulation in these two developing countries.<\/jats:p><\/jats:boxed-text>\n<\/jats:p><\/jats:sec>","DOI":"10.1002\/cpt.2128","type":"journal-article","created":{"date-parts":[[2020,12,6]],"date-time":"2020-12-06T09:30:16Z","timestamp":1607247016000},"page":"1564-1574","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Developing and Validating a Clinical Warfarin Dose\u2010Initiation Model for Black\u2010African Patients in South Africa and Uganda"],"prefix":"10.1111","volume":"109","author":[{"given":"Innocent G.","family":"Asiimwe","sequence":"first","affiliation":[{"name":"The Wolfson Centre for Personalized Medicine and MRC Centre for Drug Safety Science Department of Pharmacology and Therapeutics Institute of Systems, Molecular and Integrative Biology University of Liverpool 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