Implementer report: ICD-10 code F44.5 review for functional seizure disorder

Objective The study aimed to measure the validity of International Classification of Diseases, 10th Edition (ICD-10) code F44.5 for functional seizure disorder (FSD) in the Veterans Affairs Connecticut Healthcare System electronic health record (VA EHR).Methods The study used an informatics search tool, a natural language processing algorithm and a chart review to validate FSD coding.Results The positive predictive value (PPV) for code F44.5 was calculated to be 44%.Discussion ICD-10 introduced a specific code for FSD to improve coding validity. However, results revealed a meager (44%) PPV for code F44.5. Evaluation of the low diagnostic precision of FSD identified inconsistencies in the ICD-10 and VA EHR systems.Conclusion Information system improvements may increase the precision of diagnostic coding by clinicians. Specifically, the EHR problem list should include commonly used diagnostic codes and an appropriately curated ICD-10 term list for ‘seizure disorder,’ and a single ICD code for FSD should be classified under neurology and psychiatry.