The United State's particular version of ICD-10 increases the number of possible codes by an order of magnitude over ICD-9, and it's taking flak for being overly complicated. (A September 13 story in The Wall Street Journal poked fun at the industry's coming ability to code for macaw attacks and chicken-coop injuries, and included a search tool so that readers could find their own proofs of absurdity.)
Nonetheless, once it's all done, there may be reasons to be glad that the United States brought its coding practices into the 21st century.
First and foremost, ICD-10 is modern in terms of what the other kids are coding with.
Did you know that .03 percent of PC users haven't upgraded from Windows 98? When it comes to diagnosis and procedure coding, the United States is like those Win98 users: frustrated at the current system's limitations but daunted by the hassle of switching, which gets worse the longer they wait.
ICD-9 is a creaky mess and going to ICD-10 is as much of a no-brainer as ditching a 1990s-era operating system, contends Sue Bowman, director of coding policy and compliance at AHIMA.
"I don't think most other countries have looked at the transition like the U.S. has," she says. "They assumed that the need to move to the next version was obvious, because the newer version is more clinically relevant and up to date, because ICD-9 lacks space, and because it's necessary to maintain global data comparability."
While no other country uses ICD codes quite the way the U.S. plans to do, 138 countries use ICD-10 for tracking mortality, 99 use it for tracking morbidity, and Canada, Australia, and several European countries use it for some form of case-mix or reimbursement management.
The U.S. version-ICD-10-CM-contains nearly six times more codes than the international version maintained by the World Health Organization. Canada and Australia, among other countries, also have extensively modified their versions of the international system.
Putting aside macaw attacks, ICD-10 also contains numerous new distinctions that will be useful day to day. For example, unlike ICD-9, ICD-10 distinguishes easily and thoroughly among the various types of diabetes, says consultant Steven Steindel, formerly the Center for Disease Control's director of data standards and vocabulary and CDC liaison to the National Committee for Vital Health Statistics. (He speculates that he's one of the few people who's looked at every single one of the 140,000+ ICD-10 codes in the U.S. version.)
"[Type 2] diabetes is one of the most critical public health issues facing us, and ICD-10 will provide us with so much more information," Steindel says. ICD-10 has more than 250 diabetes-related codes, separating Type 1, Type 2, gestational diabetes, and diabetes caused by various drugs or other underlying conditions.
Steindel and several colleagues compared ICD-10-CM with ICD-9-CM chapter by chapter, and found that some chapters grew a lot more than others.
The ones dealing with diseases of the respiratory system and digestive system have only about 40 percent more codes than the corresponding chapters of ICD-9. The chapter dealing with the musculoskeletal system and connective tissue has 16 times more codes, partly because for the first time it includes separate codes for left and right, and digits on hands and feet (521 for each finger and more than a thousand for the thumb).
The big explosion (there's a bunch of codes for that, including injuries caused by boiler explosions and tire, pipe or hose explosions) comes in the chapter enumerating causes of injury, which is 26 times bigger than ICD-9 and includes apparent wackiness like separate codes for injuries from water skis catching on fire and injuries from water skis being crushed. However, such distinctions could provide key product safety information to manufacturers and regulators. And the odds are that only coders in resort areas will ever need them.
"Someone asked for each of those levels of granularity or they wouldn't have gotten it," says Meryl Bloomrosen, vice president of public policy and government relations for the American Medical Informatics Association. "Someone articulated and made the case for these codes-no one sat around just thinking them up for fun."
Steindel says ICD-10's specificity will take some pressure off coders. "Coders sit and debate which ICD-9 code to use, and the natural thing is to use the one you get reimbursed more for," he says. With a more granular system, coders will have to make fewer such judgment calls.
Some of increased specificity was pushed by medical societies to better reflect how physicians think, says Kim Reid, director of ICD-10 development and training for AAPC, an association of professional coders, whose members work predominantly with physicians. For example, the chapter covering pregnancy now divides the codes up by trimester, to match how physicians assess pregnant patients."We might need to use a few different ICD-9 codes to describe a disease state and all its symptoms, but with ICD-10 we can often do the same thing with just one code," she says.
Theoretically, codes that correspond more closely with diagnoses should increase the accuracy of payment and reduce the risk that claims will be kicked back for incorrect coding.
"Physicians don't get paid on diagnosis codes, but they support the medical necessity of the procedures or the evaluation and management that's done," she says.
Steindel says ICD-10 is also more "readable" and less arbitrary than ICD-9. Even though there are a lot more codes, a trained coder can quickly narrow down the choices through deduction, much the way a librarian can predict a book's call number and location on the shelves by knowing its topic and author.