Spine coding transition from ICD-9 to ICD-10: Not taking advantage of the specificity of a more granular system

• Published in: North American Spine Society journal (NASSJ) 2020-12, Vol.4, p.100035, Article 100035
• Main Authors: Sabatino, Matthew J., Burroughs, Patrick J., Moore, Harold G., Grauer, Jonathan N.
• Format: Article
• Language: English
• Subjects: Claim reporting; Clinical coding; Clinical Studies; Codes; Data collection; Data interpretation; Health care costs; ICD; ICD-10-CM; ICD-9-CM; insurance; International classification of diseases; Spine; statistical
• ISSN: 2666-5484; 2666-5484
• DOI: 10.1016/j.xnsj.2020.100035

•Despite an increase in available ICD-10 codes for spine conditions, providers select a small proportion of less specific codes.•Providers demonstrated a bias to select less-specific diagnostic codes when available.•Providers should accurately code for spine care to benefit from the additional clarity and granularity provided by ICD-10. The transition from International Classification of Diseases, 9th Edition (ICD-9) to the 10th edition (ICD-10) in 2015 increased the number and specificity of diagnostic codes with the goal of facilitating clinical care and research possibilities. Considering the potential to default to less specified ICD-10 codes, the current study evaluated the number of codes utilized for spine-related conditions before versus after the transition to ICD-10. The numbers of patients with an index encounter for a primary spine-related non-deformity diagnosis codes indexed as “dorsopathies” were abstracted from the Humana PearlDiver dataset. As the transition from ICD-9 to ICD-10 occurred in 2015, the current study compared the year prior (ICD-9) to the year after (ICD-10). The number of ICD-9 and ICD-10 codes was assessed, and distribution of utilization was compared using the Kolmogorov-Smirnov test. In 2014, 848,623 patients were assigned one of the 100 unique ICD-9 dorsopathy codes, of which 17 codes (17% of available codes) were used for more than 1% of the patients. In 2016, 840,310 patients were assigned one of the 504 unique ICD-10 dorsopathy codes, of which 21 (4% of available codes) were used for more than 1% of the patients. The top 20 codes in 2014 (ICD-9) and the top 20 codes in 2016 (ICD-10) both represented the majority of the patient population and were not statistically differently represented (p = 0.819). Further, analysis of ICD-10 codes demonstrated a clear bias toward utilizing less specified codes. Despite a five-fold increase in available diagnostic codes for spine conditions in ICD-10, in the year after implementation providers continued to select a small proportion of less specific diagnostic codes when treating spine patients.