Table 1.

Characteristics of included studies: Evaluating vitamin D treatment in children with inflammatory bowel disease

Study	N1	Location	Design	Treatment regimen	Vitamin D levels2		Treatment duration3	Cumulative dose	Disease activity4
					Before	After
Wingate, 2014	83 (CD)	Canada	RCT	A: 400 IU/d D3; B: 2000 IU/d D3	24 ± 7.9; A: 26 ± 9.2; B: 22 ± 6.8	A: 28.8 ± 9.2 (3 mo), 28 ± 8.6 (6 mo); B: 34 ± 10 (3 mo), 34.4 ± 10.4 (6 mo)	26 (183)	A: 73200 IU; B: 366000 IU	A: < 10:83 B: < 10:88
Pappa, 2012	71 (IBD)	United States	RCT	A: 2000 IU/d D2; B: 2000 IU/d D3; C: 50000 IU/wk D2	A: 16.1 ± 1; B: 14.7 ± 0.8; C: 51.3 ± 1	A:25.7 ± 2.2 (6 wk); B:31.5 ± 1.9 (6 wk); C: 40.8 ± 2.6 (6 wk)	6 (42)	A: 84000 IU; B: 84000 IU; C: 300000 IU	A: <10:54; B: <10:54; C: <10:78
Simek, 2016	32 (IBD)	United States	RCT	A: 5000 IU/10 kg/wk D3; B: 1000 IU/10 kg/wk D3	A: 24 ± 7; B: 23.7 ± 8.5	A: 41.5 ± 9.6 (8 wk), 30.8 ± 4.2 (12 wk); B: 49.2 ± 13.6 (8 wk), 35.1 ± 8.4 (12 wk)	6 (42)	A: up to 150000 IU; B: up to 150000 IU	Unknown
Shepherd, 2015	76 (IBD)	Australia	Retrospective	< 3 yr: 200000 IU D3; 3-12 yr: 400000 IU D3; > 12 yr: 800000 IU D3	16.4 ± 3.2	58.4 ± 20.8 (1 mo); 34.8 ± 11.2 (3 mo); 27.6 ± 12.4 (6 mo)	Single dose	< 3 yr: 200000 IU D3; 3-12 yr: 400000 IU D3; > 12 yr: 800000 IU D3	10 (0-47.5) 0 mo; 2.5 (0-85) 6 mo
Santucci, 2014	61 (IBD)	United States	Retrospective	A: no treatment; B: 400 IU/d; C: 600-1200 IU/d; D: 2000 IU/d or 50000 IU/wk	45% < 30 ng/mL (baseline); 50% < 30 ng/mL; 25% < 30 ng/mL; 88% < 30 ng/mL		Unknown	Unknown	Unknown

¹Number of patients recruited (type of disease);

²Serum levels expressed as mean ± SD;

³Treatment duration expressed as days (weeks);

⁴Disease activity scores (Pediatric Crohn disease activity index or Pediatric ulcerative colitis disease activity index) at baseline unless otherwise stated. Expressed as median (range) or percentage of patients with score less than 10 (remission). IBD: Inflammatory bowel disease; CD: Crohn disease; UC: Ulcerative colitis.