Measuring the range of services clinicians are responsible for in ambulatory practice

At present, the range of services delivered in a health system is not known. Currently there are no accepted methods for defining the scope of ambulatory care. Therefore we used data from the electronic medical record and billing system of a large non-profit multi-specialty group practice to measure the number of different diagnoses that clinicians managed as well as the number of different medications, laboratory tests, imaging studies, referrals and procedures ordered.

All patient encounters and clinicians in the group practice in 2008 were eligible for inclusion in the analysis. Data were analysed cumulatively for the practice and by specialty. Quantile regression models were used to adjust for differences in full-time equivalents (FTE) among physicians at the practice.

In one year for this practice, with 324,229 patients who made 3,193,917 office visits to 578 physicians and 248 other clinicians, patients presented with 5638 primary and 6411 secondary diagnoses. Overall, patient management resulted in unique orders for 9481 medications, 1182 laboratory tests, 613 referrals, 284 imaging studies and 1701 procedures. After adjusting for FTE, physicians managed a median of 249 primary diagnoses and 347 secondary diagnoses. They ordered a median of 278 medications, 128 laboratory tests, 51 referrals, 29 imaging studies and 39 procedures.

Physicians routinely manage a substantial variety of diagnoses, medications, and other tests and procedures. Quality improvement and health services researchers have generally focused on individual services but also must consider the wide variety and range of services delivered.