CONSOLIDATED STATEMENTS OF INCOME (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Laboratory services:
Drugs-of-abuse testing services	$ 11,709	$ 10,806	$ 22,287	$ 20,446
Clinical & other laboratory services:
Other clinical and laboratory services	5,848	5,292	11,334	10,032
Net patient services, less provision for bad debts of $869 and $1,607 for the three and six months ended June 30, 2012, respectively, and $990 and $1,629 for the three and six months ended June 30, 2011, respectively	3,736	2,851	7,435	5,447
Total Clinical & other laboratory services	9,584	8,143	18,769	15,479
Clinical trial services	2,148	2,323	4,522	4,859
Product sales	6,536	5,659	12,979	11,244
Total revenues	29,977	26,931	58,557	52,028
COST OF REVENUES:
Cost of services	14,843	13,623	28,893	26,575
Cost of sales	2,503	2,222	5,177	4,555
Total cost of revenues	17,346	15,845	34,070	31,130
GROSS PROFIT	12,631	11,086	24,487	20,898
OPERATING EXPENSES:
Selling, general and administrative	9,993	8,291	18,800	16,276
Research and development	755	622	1,444	1,216
Total operating expenses	10,748	8,913	20,244	17,492
INCOME FROM OPERATIONS	1,883	2,173	4,243	3,406
OTHER INCOME (EXPENSE):
Interest expense	0	(18)	0	(42)
Other income	70	57	66	73
Total other income (expense)	70	39	66	31
INCOME BEFORE INCOME TAX EXPENSE	1,953	2,212	4,309	3,437
INCOME TAX EXPENSE	(713)	(808)	(1,573)	(1,255)
NET INCOME	$ 1,240	$ 1,404	$ 2,736	$ 2,182
BASIC EARNINGS PER COMMON SHARE	$ 0.14	$ 0.16	$ 0.31	$ 0.25
DILUTED EARNINGS PER COMMON SHARE	$ 0.14	$ 0.16	$ 0.30	$ 0.24
WEIGHTED AVERAGE NUMBER OF SHARES OUTSTANDING:
Basic	8,901,618	8,847,870	8,888,702	8,849,042
Diluted	9,126,327	9,052,714	9,099,698	9,048,185