If you're looking for data to compare your practice against, the Medical Group Management Association (MGMA) may have the answer.
The MGMA issued its 2004 Coding Profile Sourcebooks for primary care, medical and surgical specialties, pathology and radiology. The books include the most-often performed procedures and diagnoses, broken down by age and gender, for 36 specialties.
The MGMA data covers 74 million procedures during calendar year 2003, and breaks down key CPT Codes by diagnosis. The data covers younger patients as well as Medicare beneficiaries, so you can track the reasons for patient visits based on age.
You can use the MGMA data to benchmark your practice's utilization of certain codes against the national average, or see whether you're claiming a particular diagnosis more often than comparable practices. The MGMA gives the example of an ophthalmology practice that discovers it's billing for refractions less often than most other practices, thereby losing out on reimbursement.