Imaging use among employed and self-employed urologists.
OBJECTIVE
Compared to physicians paid on salary (ie employed), those who own their practice (ie self-employed) derive financial benefit from providing more care. Whether the volume based incentives of ownership influence physician use of other ancillary services, like diagnostic imaging, remains unknown. We explored this possibility among urologists.


METHODS
We used data from the National Ambulatory Medical Care Survey (2006 to 2007) to identify outpatient urology visits. We determined whether the urologist who was responsible for the encounter was employed or self-employed. We calculated the proportion of visits at which imaging was ordered, and we evaluated for a difference between visits directed by employed vs self-employed urologists. We used multivariable logistic regression to measure the relationship between urologist employment status and imaging use, adjusting for patient, provider and practice level characteristics.


RESULTS
More than 1 in 5 urology visits resulted in imaging. While imaging use did not vary by measurable patient or practice level characteristics, self-employed urologists ordered imaging more often than employed urologists (24.2% vs 13.2%, respectively, p<0.001). In fact, the odds of a patient receiving imaging were almost 2-fold greater if seen by a self-employed urologist (OR 1.84, 95% CI 1.18-2.87). On stratified analysis an independent association between employment status and imaging use was observed for urolithiasis (OR 4.76, 95% CI 1.30-17.4) and hematuria visits (OR 5.52, 95% CI 1.23-24.8).


CONCLUSIONS
Compared with employed urologists, those who are self-employed have more resource intense practice styles with respect to imaging use.
Robert Wood Johnson Foundation Clinical Scholars Program, Department of Urology, Division of Health Services Research, University of Michigan, Ann Arbor, Michigan 48105-2967, USA.
John M
JM
Hollingsworth
John D
JD
Birkmeyer
Yun S
YS
Zhang
Lingling
L
Zhang
Brent K
BK
Hollenbeck
D000293:Adolescent; D000328:Adult; D000368:Aged; D003952:Diagnostic Imaging / Q000706:statistics & numerical data*; D003950:Diagnostic Techniques, Urological / Q000706:statistics & numerical data; D004651:Employment; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians'; D014572:Urology; D055815:Young Adult