Table 2.

Three Methods for Comparing Outcomes across Antidepressant Treatment Groups

Panel A. Generalized Linear Model Regressions
	[1]		[2]		[3]
Outcome	Escitalopram - Citalopram		Citalopram - Sertraline		Escitalopram - Sertraline
	Difference	P-value	Difference	P-value	Difference	P-value
Total Drug Spendinga	104.18***	<0.01	−19.54*	0.057	86.33***	<0.01
Antidepressant Spendinga	55.67***	<0.01	−3.10***	<0.01	53.17***	<0.01
6-Month MPRb	−3.17***	<0.01	0.801	0.200	−2.26***	<0.01
1-year MPRb	−5.62***	<0.01	0.467	0.613	−5.09***	<0.01
Total Non-Drug Spendinga	150.02**	0.043	−0.947	0.990	148.23*	0.055
Two-Part Models
	Difference	Confidence Interval	Difference	Confidence Interval	Difference	Confidence Interval
Psychiatric- Related Spendingc	75.94***	21.24 To 138.22	11.69	−43.61 To 64.51	86.36***	28.45 To 149.17
Depression- Related Spendingc	25.55	−12.62 To 64.22	10.15	−26.04 To 46.28	28.59	−12.79 To 70.78
Observations	3,052		2,893		2,853

Panel B. Propensity Score Matching
	[1]		[2]		[3]
Ourcome	Escitalopram - Citalopram		Citalopram - Sertraline		Escitalopram - Sertraline
	Difference	P-value	Difference	P-value	Difference	P-value
Total Drug Spending	98.41***	<0.01	−18.33	0.110	77.53***	<0.01
Antidepressant Spending	54.81***	<0.01	−3.07***	<0.01	51.77***	<0.01
6-Month MPR	−3.31***	<0.01	0.78	0.219	−2.27***	<0.01
1-year MPR	−5.65***	<0.01	0.53	0.569	−5.06***	<0.01
Total Non- Drug Spending	177.05**	0.038	1.41	0.984	120.57	0.165
Psychiatric- Related Spending	77.20**	0.017	5.20	0.849	68.79**	0.043
Depression- Related Spending	35.83	0.093	−1.95	0.920	17.22	0.4593
Observations	3,052		2,893		2,853

Panel C. Instrumental Variables
	[1]		[2]		[3]
Outcome	Escitalopram - Citalopram		Citalopram - Sertraline		Escitalopram - Sertraline
	Difference	P-value	Difference	P-value	Difference	P-value
Total Drug Spending	62.47	0.261	−136.71*	0.082	226.47**	0.040
Antidepressant Spending	68.45***	<0.01	−8.50	0.171	57.24***	<0.01
6-Month MPR	−9.26***	<0.01	3.97	0.382	−2.56	0.658
1-year MPR	−12.81***	<0.01	2.43	0.717	−8.59	0.310
Total Non- Drug Spending	−260.00	0.523	1898.78***	<0.01	462.50	0.522
Psychiatric- Related Spending	−308.77*	0.083	351.38	0.100	−39.03	0.887
Depression- Related Spending	−283.77**	0.026	314.78*	0.075	−164.58	0.426
First Stage F- Statistic	56.50		27.44		18.15
Observations	3,052		2,893		2,853

^aindicates standard errors were obtained from seemingly unrelated equations including total drug spending, antidepressant spending, and total non-drug spending, and corrected for heteroskedasticity (“suest” command approach in Stata)

^bindicates heteroskedasticity robust standard errors were used

^cindicates that the marginal effects from a two-part model are presented with bootstrapped confidence intervals.

Note:

^***denotes p-value<0.01;

^**denotes p-value<0.05; and

^*denotes p-value<0.1.