CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Laboratory services:
Drugs-of-abuse testing services	$ 41,343	$ 39,624	$ 36,040
Clinical & other laboratory services	34,852	29,923	22,885
Clinical trial services	9,667	7,500	6,926
Product sales	22,287	20,054	18,257
Total Revenues	108,149	97,101	84,108
COST OF REVENUES:
Cost of services	54,346	49,036	45,432
Cost of sales	8,968	8,425	7,781
Total Cost of Revenues	63,314	57,461	53,213
GROSS PROFIT	44,835	39,640	30,895
OPERATING EXPENSES:
Selling, general and administrative	35,144	32,691	26,663
Research and development	2,519	2,261	2,264
Total Operating expenses	37,663	34,952	28,927
INCOME FROM OPERATIONS	7,172	4,688	1,968
OTHER (EXPENSE) INCOME:
Interest expense	(49)	(10)	(17)
Other (expense) income	(112)	167	96
Total other (expense) income	(161)	157	79
INCOME BEFORE INCOME TAX EXPENSE	7,011	4,845	2,047
INCOME TAX EXPENSE	(2,559)	(1,828)	(748)
NET INCOME	$ 4,452	$ 3,017	$ 1,299
BASIC EARNINGS PER COMMON SHARE	$ 0.50	$ 0.35	$ 0.15
WEIGHTED AVERAGE NUMBER OF BASIC SHARES OUTSTANDING	8,853,643	8,715,391	8,536,768
DILUTED EARNINGS PER COMMON SHARE	$ 0.49	$ 0.34	$ 0.15
WEIGHTED AVERAGE NUMBER OF DILUTED SHARES OUTSTANDING	9,035,895	8,867,530	8,788,663