A comprehensive exam using the 1995 Guidelines requires eight organ systems.  You may not count body areas.  The Guidelines do not give any definition about how much must be examined in each system, and auditors typically count anything within that system.  The Guidelines say,

Comprehensive -- a general multi-system examination or complete examination of a single organ system.

and

The medical record for a general multi-system examination should include findings about 8 or more of teh 12 organ systems. 

There is no CMS definition for what a "complete examination of a single organ system" is, so most auditors use the 1997 Guidelines for a single system exam.

The organ systems are:

• Constitutional (e.g., vital signs, general appearance)
• Eyes
• Ears, nose, mouth and throat
• Cardiovascular
• Respiratory
• Gastrointestinal
• Genitourinary
• Musculoskeletal
• Skin
• Neurologica
• Psychiatric
• Hematologic/lymphatic/immunologic