Table 3. Associations of MHPAEA with Changes in the Percent of Plans with BH Quantitative Treatment Limits, among Carve-In Plans.

Limit Type	Pre-Parity (2008-09) N=3,615		Transition (2010) N=2,304		Post-Parity (2011-13) N=5,725		P-value	Pre-Parity Limit, among plans with relevant limit		2009 enrollees affected
	n	%	n	%	n	%		Median	Min, Max	n	%
Inpatient or intermediate days, annual
BH combined	1512	42	139	6	108	2	<.001	30	7, 175	1,417,517	37
Mental Health only	1087	30	61	3	42	1	<.001	30	8, 165	1,388,636	36
Substance Use Disorder only	924	26	38	2	20	<1	<.001	30	6, 183	1,143,494	30
Inpatient or intermediate days, lifetime
BH combined	156	4	10	<1	24	<1	<.001	90	30, 190	217,998	6
Mental Health only	39	1	6	<1	4	<1	<.001	90	45, 150	52,040	1
Substance Use Disorder only	190	5	16	1	3	<1	<.001	60	10, 120	261,042	7
Inpatient or intermediate admissions, lifetime
Substance Use Disorder only	4	<1	2	<1	2	<1	.037	2	2, 2	15	0
Inpatient or intermediate days per admission
BH combined	30	1	13	1	16	<1	<.001	30	30, 45	10,188	0
Substance Use Disorder only	28	1	6	<1	12	<1	<.001	28	7, 45	3,645	0
Outpatient visits, annual
BH combined	1923	53	160	7	110	2	<.001	30	3, 90	1,993,811	52
Mental Health only	846	23	44	2	35	1	<.001	31	5, 60	1,025,377	26
Substance Use Disorder only	661	18	34	1	21	<1	<.001	35	5, 130	730,892	19
Outpatient visits, lifetime
BH combined	50	1	1	<1	1	<1	<.001	150	30, 400	112,324	3
Mental Health only	2	<1	0	0	0	0	.096	90	90, 90	1,866	0
Substance Use Disorder only	96	3	2	<1	4	<1	<.001	60	20, 120	95,795	2

Note: P-values are from Fisher's Exact Test. The table does not include rows for types of limits that did not exist in the data. For carve-in plans, limits were always combined INN and OON network (if there were OON benefits). Total 2009 enrollees for all carve-in plans = 3,871,04