Doctor shopping for medications used in the treatment of attention deficit hyperactivity disorder: shoppers often pay in cash and cross state lines

Figures & data

Table 1. Characteristics of non-shoppers and ADHD medication shoppers, distance travelled and number of states involved in filling opioid prescriptions.

	Non-shoppers	Shoppers^a	Heavy shoppers^b
Subjects, n (row %)	4 384 334 (99.6)	15 996 (0.4)	2134 (0.05)
Age (mean ± SD), y	24.1 ± 16.2	26.4 ± 14.7	32.8 ± 13.6
Men (%)^#	2 458 312 (56.1)	8364 (52.3)	959 (44.9)
Women (%)	1 926 022 (43.9)	7632 (47.7)	1175 (55.1)
Number of ADHD medication dispensings (median [25th–75th])	11 (6–17)	24 (18–32)	36 (29–44)
Distance travelled (median [25th–75th]), miles^#	0.2 (0–12.5)	91.9 (36.2–482.3)	333.2 (118.9–4146)
Number of states visited^#, n (column %)
1	4 197 667 (95.7)	11 616 (72.6)	1220 (57.2)
2	174 055 (4.0)	3624 (22.7)	622 (29.1)
3	11 353 (0.3)	641 (4.0)	241 (11.3)
4	1052 (0.0)	91 (0.6)	45 (2.1)
≥5	207(0.0)	24 (0.1)	6 (0.3)

SD, standard deviation; ^aSubjects who filled opioid prescriptions written by more than one prescriber with at least one day of overlap at more than two pharmacies; ^bSubjects with ≥5 shopping episodes in the 18 months of follow-up; ^#The difference between shoppers and non-shoppers, and the difference between heavy shoppers and non-shoppers is significant, p ≤ 0.0001.