Table 2: Association between patient demographic and physician office/hospital characteristics and antiplatelet agent prescribed: NAMCS, NHAMCS 2000–2007a , b.

Antiplatelet medication Characteristic Aspirin only Clopidogrel only Aspirin and clopidogrel Aspirin and dipyridamole () () () () Population estimate % value Population estimate % value Population estimate % value Population estimate % value Total 1,194,958 — 818,437 — 978,810 — 366,967 — Race  White 958,151 80.2% 0.40 581,489 71.0% 0.68 708,008 72.3% 0.91 341,339 93.0% 0.11  Black 201,745 16.9% 150,228 18.4% 203,509 20.8% 22,867 6.2%  Other 35,062 2.9% 86,720 10.6% 67,293 6.9% 2761 0.8% Region  Northeast 304,874 25.5% 0.38 82,604 10.1% 0.52 111,832 11.4% 0.47 62,510 17.0% 0.75  Midwest 217,812 18.2% 287,327 35.1% 161,843 16.5% 108,731 29.6%  South 433,594 36.3% 259,449 31.7% 466,195 47.6% 84,482 23.0%  West 238,678 20.0% 189,057 23.1% 238,940 24.4% 111,244 30.3% Age  18–44 years 65,453 5.5% 0.39 10,958 1.3% 0.03 17,561 1.8% 0.20 12364 3.4% 0.90  45–64 years 436,552 36.5% 116,735 14.3% 404,818 41.4% 95,313 26.0%  ≥65 years 692,953 58.0% 690,744 84.4% 556,431 56.8% 259,290 70.7% Gender  Female 632,517 52.9% 0.71 522,671 63.9% 0.15 192,540 19.7% <0.01 113,778 31.0% 0.22  Male 562,441 47.1% 295,766 36.1% 786,270 80.3% 253,189 69.0% Insurancec  Private insurance 355,686 29.8% 0.31 187,508 22.9% 0.47 405,119 41.4% 0.21 64,802 17.7% 0.73  Medicare 656,260 54.9% 572,429 69.9% 461,148 47.1% 267,898 73.0%  Medicaid 71,523 6.0% 26,884 3.3% 53,025 5.4% 10,678 2.9%  Other 55,345 4.6% 21,151 2.6% 14,927 1.5% 10,620 2.9% Location  MSAd 994,903 83.3% 0.82 646,403 79.0% 0.58 852,053 87.0% 0.72 224,322 61.1% 0.30  Non-MSA 200,055 16.7% 172,034 21.0% 126,757 13.0% 142,645 38.9% Setting  Physician office 711,071 59.5% 0.05 726,058 88.7% <0.01 870,856 89.0% 0.01 317,518 86.5% 0.21  Hospital OPDe 56,218 4.7% 49,195 6.0% 5,305 0.5% 8,951 2.4%  Hospital ED 427,669 35.8% 43,184 5.3% 102,649 10.5% 40,498 11.0% Year  2000-01 360,067 30.1% 0.13 107,873 13.2% 0.22 23,542 2.4% <0.01 118,183 32.2% 0.62  2002-03 244,855 20.5% 151,764 18.5% 192,779 19.7% 47,861 13.0%  2004-05 213,034 17.8% 327,148 40.0% 456,787 46.7% 104,817 28.6%  2006-07 377,002 31.5% 231,652 28.3% 305,702 31.2% 96,106 26.2%

aNAMCS: National Ambulatory Medical Care Survey, NHAMCS: National Hospital Ambulatory Medical Care Survey. bPopulation estimates were calculated using SAS-callable SUDAAN software, version 9.0.1 (Research Triangle Institute) to obtain proper variance estimations that accounted for the complex sampling design of the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey and results that were weighted to reflect national population estimates. cInsurance (payment source) does not sum to 100% because of missing data, dMSA: Metropolitan Statistical Area. eOPD: Outpatient Department.