Because the way it is designed for inpatient procedures is extremely difficult and confusing. Outpatient has been approved. They added a letter to the beginning of each category in order to massively increase the amount of codes that each section can handle. That part was relatively simple. It also increased the codes from a 4th and 5th digit, out to 6th and 7th digits for a higher degree of accuracy in coding. Well done WHO! (World Health Organization).
The problem with inpatient is that the codes are all on tables, and many of the tables overlap. The code sets have increased so dramatically that the degree of accuracy in coding can't be guaranteed. That is a huge problem since our country (US) has an entire financial system set up based on the accuracy of these codes. Other countries use them for reporting purposes, but not for reimbursement.
Have you ever seen a commercial that says something like "last year more women aged 35-50 died from lung cancer than auto accidents and snake bites together." Where do they get these figures from? From your ICD-9 (soon to be ICD-10) coding. Insurance companies are required to report diagnoses and other demographic information to the government for tracking purposes. That way they know how much research money to apply toward Black Lung Disease, Agent Orange effects, and AIDS.
So, don't hold your breath people. We will soon be introduced to ICD-12... and probably before we even begin to use ICD-10 here in the good old U.S. of A.
Author, Medical Billing, Coding, and Reimbursement
A medical billing professional for over 30 years now, I have seen a lot of changes in this field, and there are a lot more on the horizon. Follow me as we see what they mean and for who.