Discrepancies in automated, electronic medical record-based CHA2DS2-VASc scores and clinician assessment for atrial fibrillation patients

Abstract

BackgroundClinical decision support tools for atrial fibrillation (AF) should include CHA2DS2- VASc scores to guide oral anticoagulant (OAC) treatment.ObjectiveWe compared automated, electronic medical record (EMR) generated CHA2DS2- VASc scores to clinician-documented scores, and report the resulting proportions of patients in the OAC treatment group.MethodsPatients were included if they had both a clinician documented and EMR-generated CHA2DS2-VASc score on the same day. EMR scores were based on billing codes, left ventricular ejection fraction from echocardiograms, and demographics; documented scores were identified using natural language processing. Patients were deemed “re-classified” if the EMR score was ≥2 but the documented score was <2, and vice versa. For the overall cohort and subgroups (sex and age group), we compared mean scores using paired t-tests and re-classification rates using chi-squared tests.ResultsAmong 5,767 patients, the mean scores were higher using EMR compared to documented scores (4.05 [SD 2.1] versus 3.13 [SD 1.8]; p<0.01) for the full cohort, and all subgroups (p<0.01 for all comparisons). If EMR scores were used to determine OAC treatment instead of documented scores, 8.3% (n=479, p<0.01) of patients would be re-classified, with 7.2% moving into and 1.1% moving out of the treatment group. Among 2,322 women, 4.7% (n=109, p<0.01) would be re-classified, with 4.1% into and 0.7% out of the treatment group. Among 3,445 men, 10.7% (n=370, p<0.01) would be re-classified, with 9.2% into and 1.5% out of the treatment group. Among 2,060 patients <65 years old, 18.1% (n=372, p<0.01) would be re-classified, with 15.8% into and 2.3% out of the treatment group. Among 1,877 patients 65-74 years old, 5.4% (n=101, p<0.01) would be re-classified, with 4.4% into and 1.0% out of the treatment group. Among 1,830 patients ≥75 years old, <1% would move into to the treatment group and none would move out of the treatment group.ConclusionsEMR-based CHA2DS2-VASc scores were, on average, almost a full point higher than the clinician-documented scores. Using EMR scores in lieu of documented scores would result in a significant proportion of patients moving into the treatment group, with the highest re-classifications rates in men and patients <65 years old.

Screening over 100 000 patients in 39 general practices in the Netherlands for anticoagulation underprescription in atrial fibrillation: a descriptive, cross-sectional study

“…Some of these are embedded in electronic patient file software popular with Dutch GPs. While some studies show a significant increase in guideline adherence using a clinical decision tool in the electronic patient file,26 27 others found the algorithms to perform misclassification in up to 12% of patients 28. To conclude, no indisputable evidence has been provided in favour or against (assisted) automated decision making.…”