The National Ambulatory Medical Care Survey: A resource for understanding the outpatient dermatology treatment

Figures & data

Table 1. Sampling and response rates of dermatologists for NAMCS survey, 1993–2010.

Year	Sampling pool^a	Total sampled	In-scope^b	Response rate % (n)^c	Number of visit records
1993	6447	104	92	75.0 (69)	1825
1994	6445	131	106	71.7 (76)	2065
1995	6813	123	105	77.1 (81)	1886
1996	6900	110	89	69.7 (62)	2043
1997	7152	104	88	65.9 (58)	1426
1998	7572	104	87	74.7 (65)	1525
1999	7172	115	92	60.9 (56)	1488
2000	7895	145	117	66.7 (78)	1989
2001	8123	134	113	67.3 (76)	1942
2002	8198	117	91	74.7 (68)	1723
2003	8395	117	95	72.6 (69)	1800
2004	8549	117	90	70.0 (63)	1499
2005	8677	117	87	66.7 (58)	1368
2006	8618	117	93	57.0 (53)	1309
2007	8709	117	99	53.5 (53)	1496
2008	8938	117	100	55.0 (55)	1523
2009	9032	116	92	46.7 (43)	1137
2010	9115	117	97	61.9 (60)	1510

^aNumber of dermatologists in American Medical Association and American Osteopathic Association master files.

^bNumber of sampled dermatologists that met inclusion criteria.

^cProportion of in-scope sample that participated.

Table 2. Characteristics of dermatologists and their practices for survey years, NAMCS 2005–2010.

	Unweighted records (n = 297)	Estimated percent of physicians
Geographic region
Northeast	60	21.2
Midwest	72	20.5
South	94	34.5
West	71	23.9
MSA^a	277	93.7
Medical degree (MD vs. DO)	289	95.0
Type of office setting
Private solo practice	137	48.2
Private group practice	138	44.8
HMO or other prepaid practice	13	4.3
Free standing clinic/urgicenter	7	2.4
Non-Federal government clinic	1	0.2
Federally qualified health center	1	0.1
Employment status of physician
Owner	228	77.9
Employee	54	17.2
Contractor	14	4.5
Blank	1	0.5
During past week, made any: (yes)
Home visits	7	2.2
Hospital visits	71	24.8
Telephone consults	142	50.2
E-mail consult	36	12.7
Electronic medical record
All electronic	60	18.8
Part paper, part electronic	28	8.8
All paper	207	71.4
Blank	2	1
Submit claims electronically
Yes	193	63.3
No	71	25.5
Unknown/Blank	33	11.2
% of revenue from medicare
<25%	108	37.3
25–50%	137	44.7
51–75%	28	8.7
>75%	9	3.9
Unknown/blank	15	5.4
% of revenue from medicaid
<25%	277	93.2
25–50%	4	1.0
51–75%	0	–
>75%	0	–
Unknown/blank	15	5.8
% of revenue from private insurance
<25%	58	19.9
25–50%	101	32.1
51–75%	95	32.8
>75%	27	9.6
Unknown/blank	16	5.6
% of revenue from patient payment
<25%	196	78.2
25–50%	23	9.9
51–75%	7	3.4
>75%	7	2.6
Unknown/blank	14	5.9
% of revenue other source
<25%	270	91.1
25–50%	5	1.4
51–75%	1	0.2
>75%	1	0.3
Unknown/blank	20	7.0
Number of managed care contracts
0	36	13.0
<3	36	13.4
3–10	114	37.1
>10	101	34.5
Unknown/blank	10	2
Accepting new patients
Yes	279	94.0
No	14	4.5
Unknown/blank	4	1.5
For new patients, accept the following:
Capitate private insurance	129	43.6
Non-capitate private insurance	209	69.9
Medicare	258	86.5
Medicaid	134	41.7
Workers compensation	112	34.0
Self-pay	262	88.3
No charge	140	48.7
Who completes the visit records for NAMCS
Physician	44	16.6
Office staff	90	28.8
Census field representative	116	37.0
Other	8	3.2
Multiple categories checked	32	11.7
Unknown/Blank	7	2.7

^aMetropolitan Statistical Area.

Table 3. Dermatology visit characteristics, NAMCS data.

	Unweighted records (n = 29 554)	Estimated percent of visits
Sex – Female	16 998	57.5
Race
White	25 468	84.8
Black	1330	4.7
Other^a	964	3.2
Blank, missing	1792	7.4
Race – imputed
White	27 069	91.4
Black	1438	5.1
Other	1047	3.5
Ethnicity
Hispanic/Latino	1264	3.8
Non-Hispanic/Latino	23 988	79.2
Unknown/Blank	4302	17.0
Expected main payment type^b
Private insurance	13 159	61.6
Medicare	5265	24.2
Medicaid or CHIP/SCHIP	419	2.0
Worker’s compensation	23	0.1
Self-pay	1639	6.7
No charge/charity	99	0.4
Other	317	1.4
Unknown/Blank	814	3.6
Patient has been seen before  graphical region	22 491	76.8
Northeast	6015	22.4
Midwest	6018	20.2
South	9343	34.0
West	8178	23.3
Percent poverty in patient zip code^c
<5%	2183	28.4
5–9.99%	2175	31.7
10–19.99%	1781	27.5
20+%	463	6.9
Unknown/Blank	418	5.5
Median household income in  patient’s zip code^c
Quartile 1 ($32,793 or less)	868	14.1
Quartile 2 ($32,794–$40,626)	1174	18.0
Quartile 3 ($40,627–$52,387)	1736	25.5
Quartile 4 ($52,388 or more)	2779	36.9
Unknown/Blank	418	5.5
% of adults with Bachelor’s degree  or higher in patient’s zip code^c
Quartile 1 (<12.84%)	840	13.9
Quartile 2 (12.84–19.66%)	1182	18.7
Quartile 3 (19.67–31.68%)	1488	22.0
Quartile 4 (31.69+%)	3047	40.0
Unknown/Blank	418	5.5
Urban–rural classification of  patient’s zip code^c
Large central metro	2161	28.1
Large fringe metro	1777	26.5
Medium metro	1561	23.5
Small metro	393	5.5
Non-metro (micropolitan  and non-core)	832	13.2
Unknown/Blank	251	3.2

^aIncluding Asian, Native Hawaiian or other Pacific Islander, American Indian or Alaska Native, and more than one race reported.

^bData collected from 1997 to 2010.

^cData collected from 2006 to 2010.

Table 4. Comparison of data collected by the NAMCS and the American Academy of Dermatology Association (AADA).

	NAMCS		DPPS
Years studied	2005–2010		2009
Annual sample size	118		3999
Response rate	66%		29%
Geographic region	Northeast	21.2%	Midwest	18.8%
	Midwest	20.5%	Northeastern	26.4%
	South	34.5%	Pacific	15.0%
	West	23.9%	Rocky Mountain	6.8%
			Southern	32.3%
			Other	0.7%
Work setting	Private solo	48.2%	Solo	39.%
	Private group	44.8%	Derm Group w/2 derms	16.7%
	HMO or other prepaid practice	4.3%	Derm Group w/3–5 derms	16.3%
			Derm Group w/6 or more derms	7.6%
	Free standing clinic	2.4%	Multispecialty Group	8.9%
	Non-Federal government clinic	0.2%	Academic	8.0%
	Federally qualified health center	0.1%	Veterans Administration	0.6%
			Military	0.9%
			Other	0.9%
			NR	0.6%
Type of community served	Large central metro	28.1%	Urban	35%
	Large fringe metro	26.5%	Suburban	54.1%
	Medium metro	23.5%	Rural	10%
	Small metro	5.5%
	Non-metro (micropolitan and non-core)	13.2%
	Unknown/Blank	3.2%

Table 5. Leading diagnoses and procedures at dermatology visits, NAMCS data 1993–2010.

	Unweighted records (n = 29 554)	Percent of visits
Leading diagnoses (ICD-9CM)
Other acne (706.1)	4457	15.0
Actinic keratosis (702.0)	4430	14.6
Contact dermatitis and other eczema, unspecified cause (692.9)	2482	8.3
Benign neoplasm of skin (216.9)	2349	8.1
Other and unspecified malignant neoplasm of skin (173.9)	1949	6.4
Other seborrheic keratosis (702.19)	1800	6.5
Other psoriasis (696.1)	1207	4.3
Rosacea (695.3)	1109	3.9
Sebaceous cyst (706.2)	1049	3.5
Seborrheic dermatitis (690.1)	634	2.3
Leading Procedures (ICD-9CM)
Other local excision or destruction of lesion or tissue of skin and subcutaneous tissue (V86.30)	5626	20.9
Other anatomic and physiologic measurements and manual examinations (V89.39)	4183	13.4
Biopsy of skin and subcutaneous tissue (V86.11)	1801	6.5
Counseling (V94.49)	464	1.6
Microscopic examination of specimen from skin and other integument (V91.69)	382	1.3
Chemosurgery of skin (V86.24)	243	0.9
Removal of other therapeutic device (V97.89)	224	0.8
Other incision with drainage of skin and subcutaneous tissue (V86.04)	126	0.4

ICD-9CM – International Classification of Diseases, 9th Revision, Clinical Modifications.