Nearly every speaker at the recent HIMSS ICD-10 Forum touted the rewards of dual coding with ICD-10. Examples of rationale and anticipated advantages were flying. But something was lacking in each of the conference’s sessions. No one explained the finer nuances of dual coding. Some attendees no doubt walked away not knowing which model of dual coding was right for them — or how to cost-justify it.

This article explores two models of dual coding: concurrent and retrospective. Pros and cons for each are described, hopefully helping you determine the best approach for your organization. And in next month’s column, we’ll explore budgeting, staffing and reporting for this critical step in ICD-10 preparedness.

Two Approaches to Dual Coding

Dual coding impacts existing processes, technologies and resources. The magnitude of the impact depends on the strategy and approach adopted. Scope, volumes, staffing, resources, expected outcomes, and extension of findings into integrated initiatives all factor into the cost of a dual-coding program.

With the concurrent approach to dual coding, coders review and code current, pre-billed records in both ICD-9-CM and ICD-10-CM/PCS. They code all diagnoses and procedures in ICD-9 and then compute the MS-DRG for each. This process then is repeated in ICD-10, most commonly without the use of general equivalency mappings (GEMs) or crosswalks. The new MS-DRGs are calculated using the new grouper and compared to the MS-DRGs derived from the ICD-9 codes.

When concurrent dual-coding efforts incorporate the use of an encoder, the embedded GEMs recommendations are used. These crosswalks sometimes are used in retrospective reviews as well. One word of caution regarding GEMs, however: they may lack the clinical rules necessary to map many diagnoses and procedures accurately, resulting in fuzzier revenue impact predictions.

The concurrent approach to dual coding supplements other ICD-10 education initiatives and reduces overall education costs. It provides an ongoing assessment of physician documentation shortcomings and the opportunity to start working with physicians to improve documentation deficiencies prior to implementation of ICD-10. Concurrent dual coding also can prevent the need for a clinical documentation audit by an outside vendor. Coder skills, end-to-end transaction processing, and financial analysis of MS-DRG shifts all can be tested with concurrent dual coding. However, these three costs must be factored into the overall budget for dual coding, keeping in mind the following:

  • Initial loss of coder productivity;
  • Associated increase in DNFB days; and
  • Overtime or outsourcing to backfill day-to-day coding coverage.

The retrospective approach provides for the review of post-billed records coded in ICD-9 and then recoded using ICD-10. Organizations typically identify the cases most commonly seen in their facilities, such as the top 20 most common MS-DRGs, top MS-DRGs by volume, top revenue-producing MS-DRGs, top principal diagnoses and/or procedures, or MS-DRGs as a percentage of total discharges.

Coders can be assigned to service types (inpatient vs. outpatient) and/or service lines (orthopedic, newborns, etc.). Coders then can become subject matter experts for particular service lines, thus creating a set of “train-the-trainers” for your facility, reducing the cost of outside education.

Retrospective dual coding builds awareness of the more specific documentation necessary when coding with ICD-10. It levels out the learning curve and improves coding accuracy, proficiency and consistency for the cases that matter most. It also supports more accurate budgeting for critical service lines and high-volume patient stay types.

However, the retrospective approach means that you’re looking at charts later, and not in the current revenue cycle flow. Clinical documentation issues identified probably are longstanding ones, some of which already may have been remediated through recent training, and perhaps a few that don’t even exist in more current discharges (or at least issues that don’t pop up as frequently). The upside to retrospective dual coding using previously adjudicated and paid claims is a clearer picture of what actually was reimbursed in ICD-9 versus potential impacts in ICD-10. Finally, it also creates a potential claim population for use in end-to-end testing, because cases not only are dual coded, but also already paid.



Taking the Next Step

In working with both concurrent and retrospective dual coding programs, HRS has identified a best-practice process that is equally effective with either approach. The first step is to delineate and prioritize the scope of your dual-coding initiative. The following questions should be asked:

  • Will you be performing concurrent or retrospective dual coding?
  • Which types of accounts do you plan to dual code?
  • How many accounts will there be total? Per person? Per account type?
  • How much information will be collected, analyzed and/or integrated into other initiatives?

From here, start dual coding in small, incremental steps. Select only certain cases for dual coding and derive some baseline insights from initial dual-coding efforts. Your focus should be on the low-hanging fruit, for example:

  • Cases that involve service lines of the highest patient volumes or net revenues;
  • Cases that represent ICD-10 chapters containing the greatest number of coding changes;
  • Known areas of challenge in ICD-9 or ICD-10 (i.e. stents, vents, transfusions, sepsis, pneumonia, CHF, etc.); and
  • Cases in ICD-9 that have non-specific documentation (i.e. acuity and type of heart failure).

For example, if your physicians are not documenting heart failure acuity in ICD-9, they certainly will not be doing so in ICD-10. This was a change that emerged in the 2008 fiscal year with the implementation of MS-DRGs, meaning physicians have had five years to improve their documentation of heart failure. Similarly, the incorrect documentation and coding of hypertension, all three types, carries significant risk for loss of a CC and a shift to a lower-weighted MS-DRG. Malignant, benign and unspecified hypertension cases should be dual coded early and often.

Opportunities found during this phase can be integrated into performance improvement, compliance and training initiatives incrementally. And once the initial dual-coding program has begun, it’s time for a full-blown implementation. Experts suggest that dual coding be conducted up to one year prior to ICD-10 conversion. Beginning in 2013, efforts should extend through ICD-10 conversion and perhaps even beyond the Oct. 1, 2014 deadline.

Dual coding is a long, ongoing process that continues to yield valuable returns for providers nationwide. Day-one cost justification is the key. Join us next month when we share tips for successful staffing, budgeting and reporting for your dual-coding program!

About the Authors:

Elizabeth Stewart is the corporate director of health information management (HIM) for HRS. Her areas of expertise include coding, HIM, patient access and patient financial services, compliance, and HIPAA privacy and security. In addition to her role at HRS, she continues to serve as the executive director of the South Carolina Health Information Management Association.

Kim Carr is the clinical documentation manager for HRS. She brings nearly 30 years of HIM experience to HRS. Kim’s background includes revenue cycle improvement, coding and compliance, coding education, and denials management in a variety of provider environments and consultant settings.

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