Convoluted code mappings to ICD-10 could be costly

New research from the University of Illinois at Chicago illustrates yet another reason to get a jump on ICD-10 implementation: Mapping the 50,000 new medical diagnosis codes and 70,000 new procedure codes from ICD-9 is far from clear-cut.

The researchers produced two mapping files based on data from the Centers for Medicare & Medicaid Services--from ICD-9 to ICD-10 and the reverse. They found the two mappings are not necessarily reciprocal, according to the study published at the Journal of the American Medical Informatics Association.

In all, about 60 percent of the ICD-9 codes pose little problem in the transition, but the other 40 percent are more complex, with 36 percent of them classified as "convoluted" with entangled and non-reciprocal mappings. One percent of ICD-9 codes were found to have no corresponding codes in ICD-10.

"Indeed, there is no straightforward way to query patient data across the ICD-9-CM and ICD-10-CM divide of convoluted motifs," the authors wrote.

As an example, "accidental poisoning by unspecified drug" no longer exists in ICD-10. Instead, emergency department physicians will be required to specify the drug category, which "requires a certainty not reflecting clinical practice."

The effect would vary, based on a study of 24,008 patient visits in 217 emergency departments, the authors note.

Hematology fared best with just five percent of convoluted mappings, while that rose to 60 percent in obstetrics and injuries. With 42 percent of infectious disease code mappings convoluted, the authors wrote most specialties will be affected.

In the study, approximately 27 percent of the ED costs, encounters and codes were associated with convoluted diagnoses, posing the potential for costly errors. There was a 3.6 percent decrease of ED payments associated with convoluted diagnoses and an increase of 5.2 percent for those associated with less complex mapping categories. Based on their research, the authors have set up a web portal to help with coding complex diagnoses.

Since CMS has reiterated its position that the Oct. 1, 2014 deadline will stand, there's no time for procrastination, as FierceHealthIT has reported. Yet survey after survey finds healthcare organizations falling behind the recommended implementation timelines.

Christine Armstrong, principal at Deloitte, recently told FierceHealthIT that organizations are finding that the testing phase, when all these discrepancies are to be worked out, is taking organizations much longer than they anticipated, so it's especially important to provide plenty of time for it.

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