{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T09:54:13Z","timestamp":1792144453930,"version":"4.4.0"},"reference-count":33,"publisher":"American Diabetes Association","issue":"3","license":[{"start":{"date-parts":[[2024,2,23]],"date-time":"2024-02-23T00:00:00Z","timestamp":1708646400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.diabetesjournals.org\/journals\/pages\/license"}],"funder":[{"DOI":"10.13039\/501100004191","name":"Novo Nordisk","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100004191","id-type":"DOI","asserted-by":"publisher"}]},{"name":"NIH","award":["DK123330"],"award-info":[{"award-number":["DK123330"]}]},{"name":"NIH","award":["HD104756"],"award-info":[{"award-number":["HD104756"]}]},{"name":"UpToDate"}],"content-domain":{"domain":["diabetesjournals.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2024,3,1]]},"abstract":"<jats:sec>\n                    <jats:title>OBJECTIVE<\/jats:title>\n                    <jats:p>To examine the accuracy of different periods of continuous glucose monitoring (CGM), hemoglobin A1c (HbA1c), and their combination for estimating mean glycemia over 90 days (AG90).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESEARCH DESIGN AND METHODS<\/jats:title>\n                    <jats:p>We retrospectively studied 985 CGM periods of 90 days with &amp;lt;10% missing data from 315 adults (86% of whom had type 1 diabetes) with paired HbA1c measurements. The impact of mean red blood cell age as a proxy for nonglycemic effects on HbA1c was estimated using published theoretical models and in comparison with empirical data. Given the lack of a gold standard measurement for AG90, we applied correction methods to generate a reference (eAG90) that we used to assess accuracy for HbA1c and CGM.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS<\/jats:title>\n                    <jats:p>Using 14 days of CGM at the end of the 90-day period resulted in a mean absolute error (95th percentile) of 14 (34) mg\/dL when compared with eAG90. Nonglycemic effects on HbA1c led to a mean absolute error for average glucose calculated from HbA1c of 12 (29) mg\/dL. Combining 14 days of CGM with HbA1c reduced the error to 10 (26) mg\/dL. Mismatches between CGM and HbA1c &amp;gt;40 mg\/dL occurred more than 5% of the time.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSIONS<\/jats:title>\n                    <jats:p>The accuracy of estimates of eAG90 from limited periods of CGM can be improved by averaging with an HbA1c-based estimate or extending the monitoring period beyond \u223c26 days. Large mismatches between eAG90 estimated from CGM and HbA1c are not unusual and may persist due to stable nonglycemic factors.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.2337\/dc23-1177","type":"journal-article","created":{"date-parts":[[2024,2,23]],"date-time":"2024-02-23T16:01:23Z","timestamp":1708704083000},"page":"460-466","update-policy":"https:\/\/doi.org\/10.2337\/ada-journal-policies","source":"Crossref","is-referenced-by-count":23,"title":["Estimating Glycemia From HbA1c and CGM: Analysis of Accuracy and Sources of Discrepancy"],"prefix":"10.2337","volume":"47","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8538-9198","authenticated-orcid":false,"given":"Veronica","family":"Tozzo","sequence":"first","affiliation":[{"name":"1Department of Pathology and Center for Systems Biology, Massachusetts General Hospital, Boston, MA"},{"name":"2Department of Systems Biology, Harvard Medical School, Boston, MA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew","family":"Genco","sequence":"additional","affiliation":[{"name":"3Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH"},{"name":"4Medical Service, Cincinnati Veterans Affairs Medical Center, Cincinnati, OH"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shammah O.","family":"Omololu","sequence":"additional","affiliation":[{"name":"5University of Cincinnati, College of Nursing, Cincinnati, OH"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher","family":"Mow","sequence":"additional","affiliation":[{"name":"1Department of Pathology and Center for Systems Biology, Massachusetts General Hospital, Boston, MA"},{"name":"6Mass General Brigham Enterprise Research IS, Boston, MA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hasmukh R.","family":"Patel","sequence":"additional","affiliation":[{"name":"1Department of Pathology and Center for Systems Biology, Massachusetts General Hospital, Boston, MA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chhaya H.","family":"Patel","sequence":"additional","affiliation":[{"name":"1Department of Pathology and Center for Systems Biology, Massachusetts General Hospital, Boston, MA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samantha N.","family":"Ho","sequence":"additional","affiliation":[{"name":"1Department of Pathology and Center for Systems Biology, Massachusetts General Hospital, Boston, MA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Evie","family":"Lam","sequence":"additional","affiliation":[{"name":"1Department of Pathology and Center for Systems Biology, Massachusetts General Hospital, Boston, MA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Batoul","family":"Abdulsater","sequence":"additional","affiliation":[{"name":"1Department of Pathology and Center for Systems Biology, Massachusetts General Hospital, Boston, MA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nikita","family":"Patel","sequence":"additional","affiliation":[{"name":"1Department of Pathology and Center for Systems Biology, Massachusetts General Hospital, Boston, MA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert M.","family":"Cohen","sequence":"additional","affiliation":[{"name":"3Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH"},{"name":"4Medical Service, Cincinnati Veterans Affairs Medical Center, Cincinnati, OH"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David M.","family":"Nathan","sequence":"additional","affiliation":[{"name":"7Diabetes Research Center, Department of Medicine, Massachusetts General Hospital, Boston, MA"},{"name":"8Harvard Medical School, Boston, MA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7060-7778","authenticated-orcid":false,"given":"Camille E.","family":"Powe","sequence":"additional","affiliation":[{"name":"7Diabetes Research Center, Department of Medicine, Massachusetts General Hospital, Boston, MA"},{"name":"8Harvard Medical School, Boston, MA"},{"name":"9Department of Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA"},{"name":"10Eli and Edythe L. 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