Table 1

Description of the demographics and characteristics of each of the SCCS cohorts, and the study population of patients that they were drawn from

	Exacerbation cohort		All non-clinical switchers HES linked		Non-urgent GP consults cohort		Respiratory events cohort		Adverse inhaler events cohort		All non-clinical switchers
	N	%	N	%	N	%	N	%	N	%	N	%
Total	5242	100	23 488	100	50 289	100	51 659	100	3258	100	69 812	100
Patient characteristics
Respiratory condition
Asthma	4232	80.7	18 185	77.4	43 653	86.8	45 318	87.7	2821	86.6	59 909	85.8
COPD	1010	19.3	5303	22.6	6636	13.2	6341	12.3	437	13.4	9903	14.2
Gender
Male	2377	45.3	10 663	45.4	21 613	43.0	21 848	42.3	1190	36.5	29 925	42.9
Female	2865	54.7	12 825	54.6	28 676	57.0	29 811	57.7	2068	63.5	39 887	57.1
Age at switch, years (median, IQR)	68.2 (58–76)		69.6 (62–77)		63.6 (50–73)		63.4 (50–73)		67.0 (57–75)		62.7 (49–73)
Socioeconomic status
1 (least deprived)	597	11.4	2663	11.3	3829	13.6	3733	13.3	177	10.2	5085	13.5
2	1018	19.4	4557	19.4	5010	17.8	5184	18.5	372	21.4	7114	18.9
3	1011	19.3	4689	20.0	5292	18.8	5217	18.6	268	15.4	7245	19.2
4	1147	21.9	4998	21.3	5813	20.7	5957	21.2	356	20.4	7751	20.5
5	1469	28.0	6581	28.0	8158	29.0	7987	28.4	569	32.7	10 544	27.9
Smoking
Never	1281	24.4	6104	26.0	10 923	21.7	11 860	23.0	686	21.1	16 264	23.3
Ex-smoker	2678	51.1	5916	25.2	14 382	28.6	14 219	27.5	884	27.1	19 288	27.6
Current	1283	24.5	11 468	48.8	24 984	49.7	25 580	49.5	1688	51.8	34 260	49.1
COPD, inhaler use preswitch
ICS alone	119	11.8	764	14.4	822	12.4	748	11.8	41	9.4	1291	13.0
LABA alone	23	2.3	91	1.7	117	1.8	103	1.6	3	0.7	180	1.8
LAMA alone	63	6.2	481	9.1	537	8.1	515	8.1	23	5.3	971	9.8
LABA and ICS	219	21.7	1165	22.0	1382	20.8	1296	20.4	90	20.6	2029	20.5
LABA and LAMA	17	1.7	137	2.6	164	2.5	162	2.6	12	2.7	259	2.6
LAMA and ICS	41	4.1	1165	22.0	267	4.0	264	4.2	25	5.7	363	3.7
Triple therapy	528	52.3	2464	46.5	3347	50.4	3253	51.3	243	55.6	4810	48.6
Asthma, inhaler use preswitch
ICS only	1374	32.5	6466	35.6	16 069	36.8	16 473	36.3	829	29.4	21 847	31.3
ICS and LABA	1710	40.4	6946	38.2	17 992	41.2	18 997	41.9	1157	41.0	25 519	36.6
ICS and LABA and Add on*	1020	24.1	4264	23.4	8615	19.7	8856	19.5	770	27.3	11 335	16.2
Non-guideline treatment	128	3.0	509	2.8	977	2.2	992	2.2	65	2.3	1208	1.7
Inhaler technique checked
Yes	2003	38.2	7867	33.5	19 010	37.8	21 341	41.3	1369	42.0	25 025	35.8
No	3239	61.8	15 621	66.5	31 279	62.2	30 318	58.7	1889	58.0	44 787	64.2
Adverse medication events
Yes	135	2.6	676	2.9	1335	2.7	1567	3.0	1435	44.0	1975	2.8
No	5107	97.4	22 812	97.1	48 954	97.3	50 092	97.0	1823	56.0	67 837	97.2
Inhaler switch characteristics
Drug class
ICS	2164	41.3	9928	42.3	22 138	44.0	22 624	43.8	1353	41.5	30 053	43.0
LABA	377	7.2	1629	6.9	3411	6.8	3189	6.2	225	6.9	4881	7.0
LABA/ICS	1850	35.3	7926	33.7	19 244	38.3	20 441	39.6	1279	39.3	27 118	38.8
LAMA	851	16.2	4005	17.1	5496	10.9	5406	10.5	401	12.3	7760	11.1
Switch between same drug(s)
No	540	10.3	2413	10.3	6169	12.3	6443	12.5	416	12.8	8731	12.5
Yes	4702	89.7	21 075	89.7	44 119	87.7	45 215	87.5	2841	87.2	61 083	87.5
Type
Brand to generic	1719	32.8	9517	40.5	20 411	40.6	20 376	39.4	1411	43.3	27 111	38.8
Generic to generic	274	5.2	1186	5.0	2590	5.2	2634	5.1	169	5.2	3722	5.3
Generic to brand	2433	46.4	9739	41.5	20 626	41.0	21 654	41.9	1258	38.6	29 086	41.7
Brand to brand	816	15.6	3037	12.9	6662	13.2	6995	13.5	420	12.9	9893	14.2
Device
MDI to DPI	411	10.1	1973	11.2	3884	10.3	3948	10.2	279	11.0	5170	9.7
DPI to DPI	1418	34.7	7101	40.5	14 209	37.6	14 291	36.9	890	35.2	20 493	38.6
DPI to MDI	601	14.7	2408	13.7	5317	14.1	5529	14.3	348	13.8	7398	13.9
MDI to MDI	1655	40.5	6058	34.5	14 381	38.1	15 013	38.7	1012	40.0	20 058	37.8
Kept new inhaler
Yes	5015	95.7	22 135	94.2	47 486	94.4	48 795	94.5	3042	93.4	65 947	94.5
No	227	4.3	1353	5.8	2803	5.6	2864	5.5	215	6.6	3865	5.5

*Add on therapy included a LAMA, leucotriene receptor antagonist or slow release theophylline.
COPD, chronic obstructive pulmonary disease; DPI, dry powdered inhaler; GP, general practitioner; HES, Hospital Episode Statistics; ICS, inhaled corticosteroid; LABA, long-acting beta agonist; LAMA, long-acting muscarinic antagonist; MDI, metered-dose inhaler; SCCS, self-controlled case series.