Table 1.

Patient, Provider, and Visit Characteristics of National Ambulatory Medical Care Survey Sample (Unweighted n = 2,964, Weighted n = 121,633,833)

	Frequency	Weighted Frequency	Percent of Visits (Weighted)
Race/ethnicity
Non-Hispanic White	2478	91,850,330	75.51
Non-Hispanic Black	164	7,532,330	6.19
Hispanic	206	13,372,045	10.99
Non-Hispanic other	116	8,879,128	7.30
Type of payment
Private insurance	404	17,932,724	14.74
Medicare	2497	101,265,017	83.25
Medicaid/CHIP	52	2,088,510	1.72
Other	11	347,583	0.29
Type of visit
New problem	893	34,348,869	28.24
Chronic problem, routine	1205	50,643,006	41.64
Chronic problem, flare-up	205	8,072,268	6.64
Preventive visit	661	28,569,691	23.49
Primary care provider—yes	2668	113,553,967	93.36
Established patient—yes	2820	116,606,883	95.87
“Does the patient now have: cancer?”
Yes	378	13,879,478	11.41
Type of provider seen^†
Physician seen	2926	119,453,948	98.21
Physician assistant seen	114	3,178,117	2.61
Nurse practitioner/midwife seen	83	3,528,765	2.90
Type of doctor seen
MD—doctor of medicine	2599	110,605,835	90.93
DO—doctor of osteopathy	365	11,027,998	9.12
Type of practice (solo/nonsolo)
Nonsolo	1958	76,949,970	63.26
Rural—yes	593	19,335,184	15.90
Survey year
2013	1208	26,139,690	21.49
2014	1079	24,881,460	20.46
2015	329	26,557,922	21.83
2016	188	18,515,875	15.22
2018	160	25,538,886	21.00

	Mean	Standard Error of Mean
Patient age—years	77.95	0.23
Total number of chronic conditions
Total number of services ordered or provided during visit^*
Number of medications coded	2.87	0.06
Time spent with physician—minutes
	6.29	0.14
	5.78	0.28
	21.46	0.46

Abbreviation: CHIP, Children’s Health Insurance Program.
↵* Total number of services reported as ordered or provided during the visit. Includes vital signs and write-in entries.
† Types of providers seen during visits are not mutually exclusive and do not add up to 100%; multiple provider types could have been included in the visit.