Appendix Table 6.

Multivariable-Adjusted Proportions of Utilization, by Clinician Type, in Hospital Clinics (NHAMCS)^*

Variable	Physician (Reference) (n = 13 359)	Nurse Practitioner Only (n = 1400)	P Value	Nurse Practitioner and Physician (n = 191)	P Value	Physician Assistant Only (n = 1152)	P Value	Physician Assistant and Physician (n = 204)	P Value
Antibiotics	51.9	52.7	0.88	48.1	0.56	52.8	0.83	47.7	0.70
CT/MRI	7.3	5.4	0.25	13.7	0.056	6.6	0.68	3.9	0.182
Radiography	12.2	12.0	0.91	13.5	0.68	10.6	0.31	15.0	0.45
Referral to other physician	14.8	19.4	0.22	23.5	0.044	16.6	0.38	19.5	0.25

CT = computed tomography; MRI = magnetic resonance imaging; NHAMCS = National Hospital Ambulatory Medical Care Survey.

^*Values are percentages. Proportions may not match percentages because the percentages represent national estimates based on population weighting. Boldface values indicate comparisons with P < 0.05.