Assessment of ICD-10-CM code assignment validity for case finding of outpatient anticoagulant-related bleeding among Medicare beneficiaries.

PURPOSE

To assess performance of International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code assignments for identifying bleeding events resulting in emergency department visits and hospitalizations among outpatient Medicare beneficiaries prescribed anticoagulants.

METHODS

Performance of 206 ICD-10-CM code assignments indicative of bleeding, five anticoagulant adverse effect/poisoning codes, and five coagulopathy codes (according to Medicare Parts A and B claims) as assessed among Medicare fee-for-service beneficiaries prescribed anticoagulants between October 1, 2015 and September 30, 2016 (according to Part D claims). Structured medical record review was the gold standard for validating the presence of anticoagulant-related bleeding. Sensitivity was adjusted to correct for partial verification bias due to sampling design.

RESULTS

Based on the study sample of 1166 records (583 cases, 583 controls), 57 of 206 codes yielded the optimal performance for anticoagulant-related bleeding (diagnostic odds ratio, 51; positive predictive value (PPV), 75.7% [95% CI, 72.0%-79.1%]; adjusted sensitivity, 70.0% [95% CI, 63.2%-77.7%]). Codes for intracranial bleeding demonstrated the highest PPV (85.0%) and adjusted sensitivity (91.0%). Bleeding codes in the primary position demonstrated high PPV (86.9%), but low adjusted sensitivity (36.0%). The adjusted sensitivity improved to 69.5% when codes in a secondary position were added. Only one adverse effect/poisoning code was used, appearing in 7.8% of cases and controls (PPV, 71.4% and adjusted sensitivity, 6.8%).

CONCLUSIONS

Performance of ICD-10-CM code assignments for bleeding among patients prescribed anticoagulants varied by bleed type and code position. Adverse effect/poisoning codes were not commonly used and would have missed over 90% of anticoagulant-related bleeding cases.