ICD-10 Cheat Sheet: DIY for Physicians

Aug. 6, 2015 / By Rhonda Butler

Did you end up here because you haven’t done squat about ICD-10, and you googled “ICD-10 cheat sheet?” Fantastic. Come on in, there’s plenty of room. I could get all high and mighty about cheat sheets, but by temperament I am practically allergic to telling people what to do. So, if you want to stick with the cheat sheet for coding in ICD-10, I will not try to talk you out of it.

By the way, there are cheat sheets for sale by physician specialty. I haven’t seen them, I don’t know what they cost in dollars, or what they ultimately cost you—for example, in contact information you have to fork over. Since you are reading this blog I take it you are a fellow DIYer and you want to build your own cheat sheet from first principles. Excellent. Let’s scrub up and get you started.

First, the easy ones. For many physician specialties, a reasonable sized cheat sheet that contains the most common diagnosis codes used in your practice is quite doable. For many physicians, the number of ICD-10 codes compared to ICD-9 is pretty modest. Here is a quickie comparison to ICD-9 to ICD-10 by specialty.

Specialty Number of ICD-9 codes Number of ICD-10 codes Comments
Gastroenterology 596 706
Pulmonology 255 336
Urology 389 591 That’s actually an inflated number because it includes some reproductive system stuff
Endocrinology 335 675
Neurology 459 591
Pediatrics 702 1,207 Includes both the newborn conditions chapter and the congenital anomalies chapter
Infectious disease 1,270 1,056 You guys actually lost codes. I expect to hear howls of protest- not really

I suggest you create your cheat sheet in two sessions, and limit yourself to a couple of hours for each session. Then after half a day spent actually looking at ICD-10 instead of having somebody tell you how impossibly complex ICD-10 is, you will have:

  • Direct knowledge of what ICD-10-CM looks like, instead of a bunch of second-hand factoids and scary hype
  • An actual, usable draft of a cheat sheet—a working draft, because it covers the main stuff, but it will probably get tweaked in the first months as your office discovers codes they would like added or removed

So, how do you get your hands on these codes to make your cheat sheet? A PDF of the ICD-10-CM codebook is available free for download from the CDC website. Choose the second link that says PDF format, and download the files at that link. The codebook PDF is 8 MB and it is called Tabular.pdf.

The same file is available at the CMS website. The codebook PDF is the second link in the Downloads box. Download the zip file, and the codebook file has the same file name as size as above, Tabular.pdf, 8 MB.

First two-hour session: Copy and paste from your specialty’s “home chapter”

Use the bookmarks or links in the PDF file to go to your specialty’s “home chapter.” For example, the gastroenterology home chapter is 11, Diseases of the Digestive System, and for pulmonology the home chapter is 10, Diseases of the Respiratory System.

The chapter will be divided into blocks. For specialties that don’t fit the neat model of a single home chapter, you will need to look among the chapter links and find the blocks with titles that interest you. Since the blocks often have these general titles that only hint as what is in them, you might find it most efficient to just use the word search window in your PDF reading software. For example, pediatricians and many other specialties are going to want the asthma codes. The block they are in is called, Chronic lower respiratory diseases (J40-J47), which isn’t that helpful. But if you search on the term asthma, after clicking through a half dozen other uses of the word asthma in earlier chapters of the book, you’ll get to the asthma category, J45, where you can copy the codes you want.

Some blocks you can skip altogether. For gastroenterology, the first block is chapter 11 is diseases of the oral cavity and salivary glands, and contains 12 pages of codes you can probably skip. That means you can go straight to page 500 of 530 and start shopping for codes.

Two pointers for the shopping part:

  1. Don’t work too hard. Rely on your recognition of the condition described in the code title. Look for the stuff you see day in and day out. Is this a diagnosis, or a synonym of a diagnosis (or an “other specified” that includes a diagnosis) that you commonly use in your office now? If the answer is yes, copy and paste the code into your ICD-10 draft cheat sheet.
  2. When you copy and paste a code, make sure you get the complete, valid code for that condition. The codebook has headers at every section, category, sub-category, indented underneath each other all the way down. ICD-9 is arranged pretty much the same way. Make sure you copy and paste the complete code and not the header above it. Otherwise you will end up submitting an invalid code, and you know what happens next. Lots of time gets wasted. An example is gastroesophageal reflux disease. K21 Gastro-esophageal reflux disease is the header, and indented underneath the header are the two complete codes, K21.0 Gastro-esophageal reflux disease with esophagitis and K21.9 Gastro-esophageal reflux disease without esophagitis. The two codes are complete and valid codes, and the header above them is not.

Second two-hour session: Supplement as needed

For this session you may want to work from your ICD-9 cheat sheet, or you may want to even work from memory to start with. The question you are trying to answer here is, what other super common conditions do I end up coding day in and day out? Depending on the specialty (or not) the answer may be something like: type 2 diabetes, asthma, hypertension, morbid obesity. You get the idea.

To find these other diagnoses you want on your cheat sheet, you can use the Adobe word search in the Tabular.pdf file you used in the first session, or you can use the traditional ICD index and look up the codes. You still have to go back to the tabular PDF to find the complete, valid code and make sure it is the one you want. The index PDF is among the files you downloaded when you got the tabular PDF, and the file name is Index.pdf.

So, if you are game to try this for yourself, and your specialty is one where the increase in the number of codes is pretty modest, this will get you started. Yes, it is quick and dirty, but it’s a start, and you have to start somewhere, or get someone else to do it for you.

For those of you in the specialties where the number of codes has gone up significantly—orthopedists, OB/GYN docs and oncologists, for example—it takes a bit more work to build a cheat sheet of reasonable size. Let’s call it an “interesting challenge” and take a look at how it can be done in the next blog.

Rhonda Butler is a senior clinical research analyst with 3M Health Information Systems.


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