All Nonpersistent in Initiation Year		Switch in Initiation Year			Discontinue in Initiation Year			Did Not Switch or Discontinue but Nonpersistent in Initiation Year
	N	%	N	%	P Valuea	N	%	P Valuea	N	%	P Valuea
Total	607	-	174	29.00		347	57.00		86	14.00
Gender					0.552			0.820			0.274
Male	171	28.17	52	29.89		99	28.53		20	23.26
Female	436	71.83	122	70.11		248	71.47		66	76.74
Age group					0.920			0.692			0.585
0-35	107	17.63	29	16.67		65	18.73		13	15.12
36-44	187	30.81	57	32.76		105	30.26		25	29.07
45-54	208	34.27	59	33.91		114	32.85		35	40.70
55+	105	17.30	29	16.67		63	18.16		13	15.12
Payer type					0.184			0.290			0.767
Commercial	369	60.79	116	66.67		203	58.50		50	58.14
Medicaid or Medicare	13	2.14	0	0.00		11	3.17		2	2.33
Self-insured	225	37.07	58	33.33		133	38.33		34	39.53
Insurance type					0.137			0.594			0.155
Health maintenance organization	75	12.36	26	14.94		40	11.53		9	10.47
Indemnity	25	4.12	11	6.32		11	3.17		3	3.49
Preferred provider network	449	73.97	125	71.84		259	74.64		65	75.58
Point of service	49	8.07	12	6.90		32	9.22		5	5.81
Consumer driven	4	0.66	0	0.00		2	0.58		2	2.33
Unknown	5	0.82	0	0.00		3	0.86		2	2.33
Region					0.055			0.212			0.859
East	186	30.64	63	36.21		97	27.95		26	30.23
Midwest	165	27.18	44	25.29		99	28.53		22	25.58
South	194	31.96	57	32.76		110	31.70		27	31.40
West	62	10.21	10	5.75		41	11.82		11	12.79
MS-related symptoms b
Visual	128	21.09	39	22.41	0.612	74	21.33	0.868	15	17.44	0.371
Movement disorders	155	25.54	45	25.86	0.907	90	25.94	0.793	20	23.26	0.601
Facial neuralgia	17	2.80	10	5.75	0.005	5	1.44	0.019	2	2.33	0.773
Dizziness	63	10.38	22	12.64	0.246	30	8.65	0.106	11	12.79	0.429
Fatigue	14	2.31	3	1.72	0.545	10	2.88	0.275	1	1.16	0.446
Paralysis	27	4.45	7	4.02	0.747	18	5.19	0.307	2	2.33	0.303
Headache	8	1.32	2	1.15	0.817	4	1.15	0.680	2	2.33	0.376
Muscle	67	11.04	22	12.64	0.424	41	11.82	0.480	4	4.65	0.041
Speech	11	1.81	4	2.30	0.569	7	2.02	0.662	0	0.00	0.174
Skin disturbance	113	18.62	34	19.54	0.711	60	17.29	0.333	19	22.09	0.371
Movement aids c
Walker	16	2.64	7	4.02	0.176	9	2.59	0.940	0	0.00	0.100
Wheelchair	21	3.46	8	4.60	0.331	13	3.75	0.655	0	0.00	0.058
Prior DMT use (yes)d	315	51.89	136	78.16	< 0.001	148	42.65	< 0.001	31	36.05	< 0.001
Charlson Comorbidity Index (mean, SD)	3.48	1.91	3.51	1.94	0.810	3.53	1.86	0.445	3.21	2.01	0.162
Relapse count	0.62	1.27	0.76	1.16	0.079	0.54	1.12	0.108	0.62	1.88	0.999

^a P value difference between each nonpersistent category (i.e., switch vs. combination of discontinue and did not switch or continue but nonpersistent in initiation year); chisquared distributional test for categorical variables; t-test used for continuous variables.

^b Symptom codes identified in Table 1 published in Curkendall et al.³³

^c Movement aid codes identified in Appendix B (available in online article).

^d Prior DMT use was defined as any claim for interferon beta 1a IM, interferon beta 1a SC, interferon beta 1b SC, or glatiramer acetate during the 12-month period prior to index date.

DMT = disease-modifying therapy; ICD-9-CM = International Classification of Diseases, Ninth Revision, Clinical Modification; IM = intramuscular; SC = subcutaneous; SD = standard deviation.