Table 3 Characteristics of the population according to vitamin D status

TB status, n (%):

<0.0001

- Controls

113 (71.1%)

241 (78.2%)

460 (87%)

814 (81.7%)

- Latent TB

28 (17.6%)

52 (16.9%)

58 (11%)

138 (13.9%)

- Active TB

18 (11.3%)

15 (4.9%)

11 (2%)

44 (4.4%)

Enrolling centre, n (%):

<0.0001

- Evelina London Children’s

26 (16.4%)

23 (7.5%)

14 (2.6%)

63 (6.4%)

Hospital, London, UK

- Great Ormond Street

8 (5%)

5 (1.6%)

2 (0.4%)

15 (1.5%)

Hospital, London, UK

- Anna Meyer Children's University Hospital, Florence, Italy

125 (78.6%)

280 (90.9%)

513 (97%)

918 (92.1%)

Age, median (IQR)

6.5 (4.2-10.3)

6.6 (4–9.7)

4.8 (2.5-7.6)

5.8 (3.1-8.5)

<0.0001

Gender, n (%):

0.106

- Male

85 (53.5%)

182 (59.1%)

329 (62.2%)

596 (59.8%)

- Female

74 (46.5%)

122 (39.6%)

195 (36.9%)

391 (39.3%)

- Not known

0 (0%)

4 (1.3%)

5 (0.9%)

9 (0.9%)

Country of origin*, n (%):

<0.0001

- Asia

27 (17%)

44 (14.3%)

98 (18.5%)

169 (17%)

- Latin America

25 (15.7%)

74 (24%)

112 (21.2%)

211 (21.2%)

- Eastern Europe §

48 (30.2%)

95 (30.8%)

188 (35.5%)

331 (33.2%)

- Western Europe

4 (2.5%)

18 (5.8%)

24 (4.5%)

46 (4.6%)

- Nord Africa

7 (4.4%)

8 (2.6%)

4 (0.8%)

19 (1.9%)

- Sub-Saharan Africa

42 (26.4%)

65 (21.1%)

98 (18.5%)

205 (20.6%)

- Other

1 (0.6%)

3 (1%)

4 (0.8%)

8 (0.8%)

- Not known

5 (3.1%)

1 (0.3%)

1 (0.2%)

7 (0.7%)

Ethnic group, n (%):

<0.0001

- African

50 (30.8%)

74 (24%)

101 (19.1%)

225 (22.6%)

- Asiatic

24 (15.1%)

43 (14%)

102 (19.3%)

169 (17%)

- Caucasian

52 (32.7%)

115 (37.3%)

211 (39.9%)

378 (37.9%)

- Hispanic

27 (17%)

73 (23.7%)

111 (21%)

211 (21.2%)

- Other

1 (1.2%)

2 (0.7%)

3 (0.5%)

6 (0.6%)

- Not known

5 (3.2%)

1 (0.3%)

1 (0.2%)

7 (0.7%)

Risk factors for vitamin D

0.932

deficiency†, n (%):

- Yes

93 (58.5%)

180 (58.4%)

303 (57.3%)

576 (57.8%)

- No

66 (41.5%)

128 (41.6%)

226 (42.7%)

420 (42.2%)

Season when blood test was

<0.0001

done, n (%):

- Spring-Summer

58 (36.5%)

145 (47.1)

339 (64.1%)

542 (54.4%)

- Winter-Autumn

101 (63.5%)

163 (52.9)

190 (35.9%)

454 (45.6%)

Vitamin D level (nmol/L), median (IQR)

20 (15.5-22.5)

37.5 (32.5-42.5)

72.5 (57.5-87.5)

35 (24–54.5)

Calcium (mmol/L), median (IQR)

2.35 (2.28-2.42)

2.37 (2.3-2.43)

2.38 (2.33-2.48)

2.4 (2.26-2.46)

0.030

Phosphate (mmol/L), median (IQR)

1.5 (1.3-1.65)

1.59 (1.41-1.68)

1.65 (1.49-1.81)

1.5 (1.28-1.61)

0.001