Table 1.

Study characteristics

	Number of studies (%)		Number of studies (%)
Journal		Number of Authors
JAMA	24 (3.0)	<3	17 (2.1)
Lancet	27 (3.4)	3	89 (11.1)
NEJM	17 (2.1)	4	116 (14.4)
APAM	103 (12.8)	5	108 (13.4)
J. Peds	256 (31.8)	6	125 (15.5)
Peds	377 (46.9)	7	100 (12.4)
		>7	249 (31.0)
Study type
Therapeutic	331 (41.2)	Number of Centers**
Prognostic	403 (50.1)	1	605 (75.4)
Diagnostic	58 (7.2)	2	37 (4.6)
Economic & Decision Analysis	12 (1.5)	3	23 (2.9)
		4	15 (1.9)
Number of subjects*		5	10 (1.2)
<10	31 (3.9)	>5	112 (14.0)
11-50	109 (13.6)
51-100	91 (11.3)	Sub-Specialty
101-500	237 (29.6)	Adolescent Medicine	36 (4.5)
501-1,000	60 (7.5)	Pediatric Cardiology	47 (5.8)
1,001-5,000	131 (16.3)	Allergy & Immunology	39 (4.9)
5,001-10,000	38 (4.7)	Clinical Pharmacology	9 (1.1)
10,001-50,000	62 (7.7)	Pediatric Critical Care	17 (2.1)
50,001-100,000	9 (1.1)	Developmental Pediatrics	69 (8.6)
>100,000	34 (4.2)	Emergency Medicine	19 (2.4)
		Endocrinology & Metabolism	50 (6.2)
Region		Gastroenterology	28 (3.5)
North America	529 (65.8)	Hematology/Oncology	13 (1.6)
South America	7 (0.9)	Infectious Disease	67 (8.3)
Europe	174 (21.6)	Neonatal/Perinatal Medicine	68 (8.5)
Asia	29 (3.6)	Nephrology	13 (1.6)
Middle East	18 (2.2)	Neurology	35 (4.4)
India	2 (0.2)	Respirology	57 (7.1)
Africa	6 (0.7)	Rheumatology	8 (1.0)
Australia	39 (4.9)	Surgery	30 (3.7)
		General Pediatrics	141 (17.5)
		Other	58 (7.2)

*Number of subjects not reported in 2 studies, **Number of centers not reported in 2 studies.

JAMA – Journal of the American Medical Association, NEJM – New England Journal of Medicine, APAM – Archives of Pediatrics and Adolescent Medicine, J. Peds – Journal of Pediatrics, Peds – Pediatrics.