Medical Care
Alexander J. Mainor, JD, MPH, Nancy E. Morden, MD, MPH, Jeremy Smith, MPH, Stephanie Tomlin, MS, MPA, and Jonathan Skinner, PhD
Using an analysis of Medicare data before and after the switch, we illustrate potential pitfalls of these crosswalks. We test some available translations by measuring weekly frequencies of common conditions during the transition and reveal the discontinuity of measures temporally aligned with the adoption of ICD-10 (October 1, 2015, the first day of the fourth quarter of 2015). We then suggest addressing this problem by creating a public good for all researchers, using a web-based platform, “Dataverse” for sharing ICD-9 and comparable ICD-10 definitions, rate comparisons that quantify the discontinuity in diverse datasets (to allow adjustment for comparisons over time), and the programming code used to make the comparisons. Our exploration of inpatient diagnostic code discontinuity illustrates the problem and serves as a starting point for the envisioned shared resource that would include a broad range of datasets.