Table 1.

Institutional characteristics by site (N = 17)

Institution	Total active studies	Active studies with minors	Minimal risk	More than minimal risk	Drugs or devices	Number of studies minors (only) a	Number of subjects minors (only) a	Total number of subjects b
Institutions with nondifferentiable databases
1	4194	1030	841	189	278			112,539
2	2774	926	772	154	215			46,907
3	2017	853	713	141	156			498,709
4	3296	855	662	193	164			58,630
7	3825	489	460	29	51			0
8	800	750	450	300	285			169,305
9	1820	1700	1140	560	560			1700
10	1500	180	30	150	31			1848
11	587	577	543	34	54			23,247
12	2708	460	104	356	50			25,168
13	2.97	1739	1259	480	225			2,097,316
14	3601	1393	976	417	391			443,892
16	2980	2736	402	98	56			1,292,620
17	6221	1890	1400	490	579			7757
Institutions with differentiable databases
5	3150	483	442	41	74	186
6	4796	1177	980	197	161	199
15	2230	2147	1593	554	523	386	310,473
Total (raw)	46,173	17,677	10,990	3951	2967	671	310,473	2,390,465
Total (with imputation)	49,469	19,385	12,767	4383	3853			4,779,638
Total (with correction)	74,204	29,078	19,151	6574	5780			7,169,457

Note. Names of reporting institutions were removed for confidentiality purposes. Bolded values represent imputed values as described in the Methods section of this paper

^a denotes institutions that could distinguish between studies with minors only and those with minors and adults

^b denotes institutions that could not distinguish between studies with minors only and studies with minors and adults. Because of the imputations of six cells, minimal risk studies + more than minimal risk studies may not always = number of active studies with minors