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Extensions and Clustering – Two New Features within ICD-11 Webinar [PODCAST]

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In this episode, we’re pleased to welcome back Kristen Eglintine, Coding Supervisor at BESLER, to give us a glimpse into the upcoming webinar, Extensions & Clustering – Two New Features within ICD-11 that we’re hosting on Wednesday, May 3rd, at 1 PM ET.

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Highlights of this episode include:

  • Background on ICD-11
  • How ICD-11 is different from ICD-10
  • Purpose and intended use of extension codes
  • Pre-coordination and post-coordination
  • What challenges coders can expect

Kelly Wisness: Hi, this is Kelly Wisness. Welcome back to the award-winning Hospital Finance Podcast. We’re pleased to welcome back Kristen Eglintine. In this episode, Kristen will give us a glimpse into the upcoming BESLER webinar, Extensions & Clustering – Two New Features within ICD-11 that we’re hosting on Wednesday, May 3rd, at 1:00 PM Eastern Time. Thank you for joining us today, Kristen.

Kristen Eglintine: Hi, Kelly. Thanks for having me back. I’m really excited to join you and talk about this topic of ICD-11.

Kelly: Yes. Awesome. Well, let’s jump in. We’re talking about your upcoming webinar. ICD-11, Extensions & Clusters. The new International Classification of Diseases, 11th revision, otherwise known as ICD-11, succeeds ICD-10. Can you give us a quick background on ICD-11?

Kristen: Absolutely. And just to clarify, yes, we did really say ICD-11. It feels like, at least to me, it was just yesterday that ICD-10 went live. And as the number signifies, ICD-11 is the 11th revision of the International Classification of Diseases, which is the ICD. It replaces ICD-10 as a global standard for recording health information and causes of death. The ICD is developed and then annually updated by the World Health Organization. And the deployment of ICD-11 started way back in 2007. It was officially endorsed by WHO members in May 2019, and then officially came into effect on January 1st in 2022 with about 35 countries using ICD-11. Now, for us in the United States, our expected implementation year is 2025, so we still have a little bit of time. And then if they do any clinical modifications, implementation may not begin until the year 2027.

Kelly: Okay, wow. So, we have some time there, which will go by fast. So how is ICD-11 different from ICD-10?

Kristen: So, there’s multiple things that are different. Conceptually, the changes of going from 10 to 11, they include introduction of new diagnoses, some refinement of diagnostic criteria for existing diagnoses, and then we’re taking some steps in the direction of dimensionality for some diagnoses. So, ICD-11 is based on STEM codes and extension codes. And I’m actually just talking about the diagnosis portion of ICD-11. STEM codes are for clinical entities in the tabular list that can be assigned alone. When you link a STEM code that represents a clinical state to an extension code, we now have added significant detail, and we have this multi-dimensional coding aspect of where they’re trying to get with ICD-11. The codes of ICD-11…they’re alphanumeric, which is no different from ICD-10, and they cover the range from 1A00.00 to ZZ9Z.ZZ. And now these, again, are your STEM codes.

The structure of STEM codes is the first character of the code always relates to the chapter number, and this may be a number or a letter. Codes starting with an X indicate an extension code, and these appear in an addendum titled Chapter X. This chapter has numerous codes containing information on concepts, including the stage of a disease, severity, and anatomical details to give the STEM code some more support. So, in other words, extension codes are supposed to add relevant information to STEM codes. STEM codes can stand alone, whereas, extension codes cannot. An extension code always follows a STEM code and may not occupy the first position in any code cluster.

We do have two types of extension codes. So, we have type one, and this type of extension code adds detail on the entity or disease coded from the ICD-11, chapters 1 to 26. And we have type-two extension codes, and those qualify a diagnosis and can be applied to codes from any chapter. Extension codes are not mutually exclusive. They are not a classification, and they can never be used without a STEM code for statistical purposes. Extension codes can never appear in the first position in the classification cluster. And when you have one or more extension codes and you link them, that’s when you get to coding a specific condition.

Kelly: Wow, that’s very specific. Thank you. And so what is the purpose and the intended use of extension codes?

Kristen: Yes, and that was a lot. So, I hope I wasn’t rambling there. But the purpose and the intended use of these extension codes, so one of the uses is to monitor quality and safety, as extension codes provide information on diagnosis timing or disease stages for risk adjustment. Hospitals will also use extension codes to forecast and potentially increase their case-based reimbursement system. So, extension codes will help pull profit information from clinical details, which hospitals then can use.

Kelly: Great. And so pre-coordination and post-coordination are new features and ICD-11. What do these terms mean?

Kristen: So, remember, I was just saying that ICD-11 is comprised of two types of codes: STEM codes and extension codes. Some STEM codes contain all pertinent information about a clinical concept in this pre-combined fashion. This is referred to pre-coordination, meaning the STEM code has all you need to report. So, an example of this would be a duodenal adenocarcinoma. So that is going to STEM code 2B80.00, and that is all you need to report the adenocarcinoma of the duodenum. But for other health conditions, a STEM code isn’t quite enough, and maybe further describe to any level of detail by applying one or more than one code. And then this is referred to post-coordinating. And this can be two or more STEM codes or a STEM code with one or more extension codes.

So, let’s look at a hip fracture as an example of what post-coordination may look like. So, if we have a patient who has a closed traverse hip fracture on the right side, we would use the STEM code NC72.30. And that is telling us we have the hip fracture. However, this code doesn’t give us all of the details, so we need to add a few extension codes to that. So, we have an extension code XK9K, right? And so that’s giving us our laterality. And then we have another extension code that could give us the fracture type. And then a third extension code would tell us whether that fracture was open or closed. So, you can see you’re starting with the basics in the STEM code and you’re adding all of the details in your extension codes. And that is, again, the post-coordination. A group of codes that have been post-coordinated is called the cluster. And a forward slash or an ampersand is used to show the linkage between the post-coordinated codes. In this manner, the classification can address many clinical concepts with a limited range of categories.

Kelly: Wow, thank you so much for that explanation, Kristen. So, what challenges can coders expect?

Kristen: I think, and everyone, it seems, in the industry, is expecting ICD-11 to present many challenges for coders. We are faced with detailed clinical coding content, and therefore, the coder must balance which pieces of information are important to represent the clinical condition as well as fulfill the purposes of the administration regarding quality and safety management. The level of granularity will depend on the purpose of use. So, for example, if we have a patient that presents for a surgery with a cancer diagnosis, clinical information for your case assignment needs less granularity in the histopathological details of the malignancy than your cancer registry would require.

As far as another challenge, hospitals and coders will need to engage a system of computer-assisted coding. And this is because the high level of granularity of coding can be regarded as a limitation for coders. Detailed knowledge about availability of specific codes is necessary to accurately report a clinical condition in ICD-11. Computer-assisted code assignment is imperative for high-quality coding as the code abstraction from printed materials can be time-consuming and was not considered when they were developing ICD-11. And then this whole concept of computer-assisted coding may be new to smaller hospitals. So, with all of that, I think it’s going to be quite a challenge transitioning from ICD-10 to ICD-11.

Kelly: Yeah, it sounds like it. So, any final thoughts for us, Kristen?

Kristen: I just would highly suggest if you would like to learn more about ICD-11, extension and cluster codes and stem codes, please join us for our webinar. It is Wednesday, May 3rd, 1:00 PM Eastern Standard Time. The visual breakdown of the new codes helps immensely when trying to understand how we will be reporting clinical conditions under ICD-11 in the near future. So, if you have some time, join the webinar. A lot of what I just went over just makes a lot more sense. It’s easier to digest when you can look at the screen on a webinar and we can present the clinical condition, what the codes looked like in ICD-10, and moving forward, what you will need to report for ICD-11.

Kelly: That makes a lot of sense. Well, thank you so much for joining us today, Kristen, and for sharing all this great information leading up to your upcoming webinar, Extensions & Clustering – Two New Features within ICD-11, that you’re presenting on May 3rd, 1 PM Eastern Time. And as a bonus, people can earn CPE. Thanks again, Kristen, for joining us.

Kristen: Well, thanks for having me, Kelly. I hope everyone has a nice day. Thank you.

Kelly: Thank you. And thank you all for joining us for this episode of The Hospital Finance Podcast. Until next time…

[music] This concludes today’s episode of the Hospital Finance Podcast. For show notes and additional resources to help you protect and enhance revenue at your hospital, visit The Hospital Finance Podcast is a production of BESLER | SMART ABOUT REVENUE, TENACIOUS ABOUT RESULTS.


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