4. Accounts Receivable and Net Patient Service Revenue:

Accounts receivable, net consists of the following (in thousands):


	December 31,
	2011			2010
Gross accounts receivable	$	806,418		$	603,372
Allowance for contractual adjustments and uncollectibles		(576,030	)		(421,977)

	$	230,388		$	181,395

Net patient service revenue consists of the following (in thousands):


	Years Ended December 31,
	2011			2010			2009
Gross patient service revenue	$	4,851,500		$	4,140,312		$	3,658,459
Contractual adjustments and uncollectibles		(3,362,081	)		(2,825,827	)		(2,444,222	)
Hospital contract administrative fees		98,829			87,074			74,027

	$	1,588,248		$	1,401,559		$	1,288,264

Accounts receivable of $230.4 million and $181.4 million at December 31, 2011 and 2010, respectively, consist primarily of amounts due from government-sponsored healthcare programs and third-party insurance payors for services provided by the Company's affiliated physicians.

Net patient service revenue of $1.6 billion, $1.4 billion and $1.3 billion for the years ended December 31, 2011, 2010 and 2009, respectively, consists primarily of gross billed charges for services provided by the Company's affiliated physicians less an estimated allowance for contractual adjustments and uncollectibles to properly account for the anticipated differences between gross billed charge amounts and expected reimbursement amounts.

The Company's contractual adjustments and uncollectibles as a percentage of gross patient service revenue vary slightly each year depending on several factors, including improved managed care contracting, changes in reimbursement from state Medicaid programs and other government-sponsored programs, shifts in the percentage of patient services being reimbursed under government-sponsored programs and annual price increases.

The Company's annual price increases typically increase contractual adjustments as a percentage of gross patient service revenue. This increase is primarily due to Medicaid and other government-sponsored health care programs that generally provide for reimbursements on a fee-schedule basis rather than on a gross charge basis. When the Company bills these programs, like other payors, on a gross-charge basis, it also increases its provision for contractual adjustments and uncollectibles by the amount of any price increase, resulting in a higher contractual adjustment percentage.