Table 1.

Percentage of Cohort, Total Prescription Drug Costs Accounted for, Demographic Characteristics, and Health Status for Prescription Drug User Groups in 2011

	Persistent Nonusers	Persistent Low‐Cost Users	Persistent Average‐Cost User	Persistent Moderate‐Cost User	Sporadic Low‐to‐High‐Cost Users	Transition to HCU	Transition from HCU	Episodic‐HCU	Persistent‐HCU
n	291,940	582,763	1,528,344	262,407	484,024	67,989	27,670	12,841	202,785
Percentage of study cohort (percent)	8.4	16.8	44.2	7.6	14.0	2.0	0.8	0.4	5.9
Percentage of total 2011 prescription drug expenditures (%)	0.0	0.3	9.9	20.5	15.8	11.0	0.4	0.2	41.9
Average prescription drug costs	$0	$12	$131	$1,587	$663	$3,266	$267	$255	$4,192
Sex (%)
Female	40	42	54	55	56	48	55	55	54
Age (%)
0–17	22	31	14	1	3	4	2	3	1
18–44	36	40	43	9	25	24	22	38	8
45–64	30	25	32	37	42	41	34	39	34
65–84	7	4	9	45	26	25	29	16	46
85+	5	0	1	9	4	5	13	3	10
Ethnicity (%)
Chinese surname	21	12	10	6	7	6	6	8	4
South Asian surname	2	3	6	3	4	5	3	5	3
Income (%)
Quintile 1	15	15	17	30	23	29	26	23	34
Quintile 2	23	19	18	19	17	17	20	18	20
Quintile 3	23	22	20	15	17	16	17	18	15
Quintile 4	21	23	21	16	18	16	17	18	14
Quintile 5	16	21	23	20	23	20	18	22	16
Major ADGs (%)
0	94	88	75	37	54	27	50	49	21
1–2	6	12	24	52	41	56	40	45	58
3+	1	0	1	11	6	16	10	7	20
Minor ADGs (%)
0–1	85	59	29	8	13	8	26	20	6
2–3	12	30	36	27	31	25	29	31	21
4–5	3	9	23	30	29	29	23	27	28
6+	1	2	12	35	27	38	22	22	44
Death in 2011 Q4 (crude), %	0.27	0.06	0.17	1.84	0.99	1.98	8.54	2.94	2.12
Death in 2011 Q4 (age‐adjusted), %	0.28	0.27	0.34	0.80	0.70	1.46	3.48	2.72	1.03

All differences in demographics and spending across prescription drug user groups are statistically significant at p = .001.