Code Conversion Impact Factor and Cash Flow Impact of International Classification of Diseases, 10th Revision, on a Large Multihospital Radiology Practice.

PURPOSE: The 2015 conversion of the International Classification of Diseases (ICD) system from the ninth revision (ICD-9) to the 10th revision (ICD-10) was widely projected to adversely impact physician practices. We aimed to assess code conversion impact factor (CCIF) projections and revenue delay impact to help radiology groups better prepare for eventual conversion to ICD, 11th revision (ICD-11).

METHODS: Studying 673,600 claims for 179 radiologists for the first year after ICD-10's implementation, we identified primary ICD-10 codes for the top 90th percentile of all examinations for the entire enterprise and each subspecialty division. Using established methodology, we calculated CCIFs (actual ICD-10 codes ÷ prior ICD-9 codes). To assess ICD-10's impact on cash flow, average monthly days in accounts receivable status was compared for the 12 months before and after conversion.

RESULTS: Of all 69,823 ICD-10 codes, only 7,075 were used to report primary diagnoses across the entire practice, and just 562 were used to report 90% of all claims, compared with 348 under ICD-9. This translates to an overall CCIF of 1.6 for the department (far less than the literature-predicted 6). By subspecialty division, CCIFs ranged from 0.7 (breast) to 3.5 (musculoskeletal). Monthly average days in accounts receivable for the 12 months before and after ICD-10 conversion did not increase.

CONCLUSION: The operational impact of the ICD-10 transition on radiology practices appears far less than anticipated with respect to both CCIF and delays in cash flow. Predictive models should be refined to help practices better prepare for ICD-11.