Validating International Classification of Diseases Code 10th Revision algorithms for accurate identification of pulmonary embolism.

BACKGROUND

Many research investigations for pulmonary embolism (PE) rely on the International Classification of Diseases 10th Revision (ICD-10) codes for analyses of electronic databases. The validity of ICD-10 codes in identifying PE remains uncertain.

OBJECTIVES

The objective of this study was to validate an algorithm to efficiently identify pulmonary embolism using ICD-10 codes.

METHODS

Using a prespecified protocol, patients in the Mass General-Brigham hospitals (2016-2021) with ICD-10 principal discharge codes for PE, those with secondary codes for PE, and those without PE codes were identified (n = 578 from each group). Weighting was applied to represent each group proportionate to their true prevalence. The accuracy of ICD-10 codes for identifying PE was compared with adjudication by independent physicians. The F1 score, which incorporates sensitivity and positive predictive value (PPV), was assessed. Subset validation was performed at Yale-New Haven Health System.

RESULTS

A total of 1712 patients were included (age: 60.6 years; 52.3% female). ICD-10 PE codes in the principal discharge position had sensitivity and PPV of 58.3% and 92.1%, respectively. Adding secondary discharge codes to the principal discharge codes improved the sensitivity to 83.2%, but the PPV was reduced to 79.1%. Using a combination of ICD-10 PE principal discharge codes or secondary codes plus imaging codes for PE led to sensitivity and PPV of 81.6% and 84.7%, respectively, and the highest F1 score (83.1%; P < .001 compared with other methods). Validation yielded largely similar results.

CONCLUSION

Although the principal discharge codes for PE show excellent PPV, they miss 40% of acute PEs. A combination of principal discharge codes and secondary codes plus PE imaging codes led to improved sensitivity without severe reduction in PPV.