Validity and Reliability of Semiquantitative Food Frequency Questionnaires for Assessing Nutrient Intake among Preschool Children in Northwest China
Table 4
Relative validity of FFQs for preschool children.
Item (units/d)
A_FFQ
3DR
P value
SCC
ICC
%CC
%GM
%difference
Median
(P25–P75)
Median
(P25–P75)
Energy (kcal)
1802.71
(1439.81, 2059.31)
1522.51
(1313.65, 1704.75)
0.065
0.814
0.825
70
5
18.4
Carbohydrates (g)
231.44
(185.06, 273.14)
194.05
(162.54, 229.23)
0.058
0.703
0.671
65
9
19.3
Protein (g)
76.40
(61.74, 88.86)
66.94
(56.23, 77.21)
0.126
0.745
0.705
66
8
14.1
Fat (g)
55.09
(40.94, 66.53)
44.56
(36.97, 57.32)
0.047
0.545
0.707
59
15
23.6
Dietary fibre (g)
20.52
(16.03, 27.03)
17.97
(13.67, 23.12)
0.109
0.441
0.539
57
16
14.2
Cholesterol (mg)
378.93
(261.09, 482.60)
330.45
(223.63, 470.06)
0.164
0.310
0.313
48
17
14.7
Vitamin A (IU)
1057.42
(815.14, 1424.37)
998.99
(713.66, 1263.93)
0.336
0.306
0.306
44
18
5.8
Thiamin (mg)
0.90
(0.76, 1.09)
0.80
(0.66, 0.93)
0.368
0.707
0.649
56
9
12.5
Riboflavin (mg)
1.46
(1.22, 1.81)
1.37
(1.09, 1.63)
0.406
0.630
0.393
54
11
6.6
Vitamin C (mg)
87.26
(66.76, 121.74)
75.13
(48.81, 107.39)
0.132
0.321
0.338
45
17
16.1
Vitamin E (mg)
15.83
(11.57, 19.88)
12.73
(10.31, 17.46)
0.031
0.038
0.598
55
15
24.4
Niacin (mg)
18.24
(14.09, 21.58)
15.90
(13.23, 19.34)
0.147
0.554
0.397
50
9
14.7
Calcium (mg)
670.08
(527.28, 834.41)
638.63
(457.12, 800.97)
0.432
0.472
0.461
55
14
4.9
Iron (mg)
28.03
(21.33, 36.05)
23.67
(19.19, 33.02)
0.042
0.518
0.454
57
12
18.4
Zinc (mg)
6.72
(5.31, 8.02)
5.90
(4.88, 7.40)
0.165
0.411
0.350
49
18
13.9
Phosphorus (mg)
955.28
(744.88, 1097.16)
887.33
(695.83, 1056.06)
0.208
0.531
0.521
50
14
7.7
Sodium (mg)
649.36
(513.53, 809.68)
570.61
(473.25, 691.78)
0.252
0.664
0.721
68
5
13.8
Selenium (mg)
23.25
(15.81, 29.45)
18.55
(14.41, 28.86)
0.046
0.168
0.210
40
19
25.3
Magnesium (mg)
429.47
(336.37, 543.28)
369.20
(298.78, 488.18)
0.182
0.612
0.627
64
7
16.3
value of t test between A_FFQ and 3DR. ICC: intraclass correlation coefficient; SCC: Spearman’s correlation coefficient; %CC: the percentage of correctly classified; %GM: the percentage of grossly misclassified; %difference in nutrient intakes between A_ FFQ and 3DR; %difference = (A_FFQ − 3DR/3DR) × 100%.
