Your June 2012 article “Medical Necessity” (p. 22) is extremely interesting and helpful. However, I would very much like to know the official, authoritative, or regulatory source or guidance of the following:

“Physicians never should report a code that represents a probable, suspected, or ‘rule out’ condition. Although facility billing might consider these unconfirmed circumstances (when necessary), physician billing prohibits this practice.”

The “ICD-9-CM Official Guidelines for Coding and Reporting Sections II.H and III.C” state:¹

Uncertain Diagnosis

If the diagnosis documented at the time of discharge is qualified as “probable,” “suspected,” “likely,” “questionable,” “possible,” or “still to be ruled out,” or other similar terms indicating uncertainty, code the condition as if it existed or was established. The bases for these guidelines are the diagnostic workup, arrangements for further workup or observation, and initial therapeutic approach that correspond most closely with the established diagnosis. (Note: This guideline is applicable only to inpatient admissions to short-term, acute-care, long-term care, and psychiatric hospitals.)

In contrast, Section IV.I, regarding outpatient services, states:

Uncertain Diagnosis

Do not code diagnoses documented as “probable,” “suspected,” “questionable,” “rule out,” or “working diagnosis,” or other similar terms indicating uncertainty. Rather, code the condition(s) to the highest degree of certainty for that encounter/visit, such as symptoms, signs, abnormal test results, or other reason for the visit. (Please note that this differs from the coding practices used by short-term, acute-care, long-term care, and psychiatric hospitals.)

I believe that all physicians’ claims for professional services in any setting must use ICD-9-CM for diagnosis coding and must follow these official coding guidelines. The guidelines state:

“Adherence to these guidelines when assigning ICD-9-CM diagnosis and procedure codes is required under the Health Insurance Portability and Accountability Act (HIPAA). The diagnosis codes (Volumes 1-2) have been adopted under HIPAA for all healthcare settings. Volume 3 procedure codes have been adopted for inpatient procedures reported by hospitals.”

There doesn’t appear to be any distinction in these guidelines between physician and facility diagnostic coding, and hospitalists (as well as other admitting physicians) are managing “inpatient admissions,” unless they are working in observation care, which is considered “outpatient” by Medicare. The reference in Sections II.H and III.C to “at the time of discharge” sounds problematic for physician claims for daily inpatient services unless the claim is not submitted until after discharge, at which time it can be determined whether the condition(s) is still qualified as “uncertain.”

Nothing in the guidelines seems to prohibit hospitalists (or other admitting physicians) from assigning “uncertain” diagnoses on claims for inpatient services (in contrast to observation and other outpatient services). If there is any other authoritative regulatory guidance that clarifies or supersedes the official guidelines, I would certainly like to see it.

Thanks so much for helping me with this difficult and confusing billing situation.

Richard D. Pinson, MD, FACP, Chattanooga, Tenn.