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Table 2 Prediction equations to correct estimates from the food-photographic record

From: Development and validation of nutrient estimates based on a food-photographic record in Japan

 

No. of meals

Regression coefficient (b)a

Intercept (a)a

Correlation coefficientb (rp)

R2c

Corrected estimates median (IQR)

% differenced after correction median (IQR)

Portion size, g

1163

0.99

0.17

0.95

0.90

93.6 (34.2, 210.7)

0.5 (−22.7, 31.1)

Energy, kcal

1163

0.95

0.29

0.95

0.90

87.0 (26.7, 203.5)

−0.4 (−24.3, 29.6)

Protein, g

1163

0.92

0.17

0.93

0.87

4.2 (1.7, 9.1)

1.7 (−25.0, 35.8)

Fat, g

992

0.90

0.22

0.88

0.77

3.2 (0.9, 8.3)

1.7 (−29.4, 50.9)

 Triglyceride, g

871

0.86

0.32

0.87

0.76

4.1 (1.2, 8.4)

4.1 (−28.3, 46.5)

 SFA, g

966

0.94

0.20

0.91

0.83

0.8 (0.1, 2.2)

9.5 (−29.2, 56.9)

 MUFA, g

928

0.91

0.16

0.91

0.82

1.1 (0.2, 3.2)

4.0 (−31.0, 53.2)

 PUFA, g

962

0.85

0.02

0.90

0.80

0.9 (0.2, 2.2)

5.6 (−28.5, 55.2)

 Cholesterol, mg

658

0.66

1.28

0.74

0.55

29.9 (13.9, 58.3)

2.5 (−39.0, 71.4)

Carbohydrate, g

1147

0.89

0.28

0.93

0.86

6.2 (2.6, 17.8)

−0.5 (−24.9, 34.8)

Total dietary fiber, g

931

0.80

0.10

0.83

0.69

1.2 (0.6, 2.0)

−0.1 (−23.8, 31.8)

 Water soluble, g

849

0.77

−0.18

0.83

0.68

0.3 (0.1, 0.5)

−1.8 (−26.1, 31.9)

 Water insoluble, g

878

0.79

0.02

0.83

0.69

0.9 (0.4, 1.5)

−3.1 (−24.1, 30.6)

Sodium, mg

1163

0.92

0.45

0.85

0.72

302.3 (173.4, 496.3)

−7.1 (−30.9, 29.0)

Potassium, mg

1163

0.89

0.65

0.91

0.82

167.9 (76.1, 308.4)

2.7 (−24.0, 33.5)

Calcium, mg

1163

0.89

0.43

0.91

0.82

25.9 (11.0, 46.4)

0.6 (−24.9, 37.7)

Magnesium, mg

1154

0.87

0.39

0.88

0.77

16.7 (8.1, 28.4)

−0.9 (−22.5, 29.6)

Phosphorus, mg

1163

0.91

0.41

0.91

0.83

68.5 (31.4, 127.1)

0.3 (−24.9, 32.7)

Iron, mg

1128

0.88

−0.07

0.89

0.79

0.6 (0.2, 0.9)

−3.5 (−25.2, 32.0)

Zinc, mg

1154

0.91

−0.02

0.90

0.81

0.4 (0.2, 0.9)

−0.2 (−26.6, 32.6)

Copper, mg

1153

0.88

− 0.34

0.91

0.82

0.06 (0.02, 0.11)

−3.2 (−23.5, 28.7)

Manganese, mg

1033

0.86

−0.30

0.88

0.78

0.1 (0.03, 0.23)

−1.8 (−26.6, 33.8)

Iodine, μg

777

0.46

0.27

0.50

0.25

1.9 (1.0, 3.6)

−3.4 (−69.1, 137.8)

Selenium, μg

805

0.83

0.11

0.77

0.59

2.2 (1.1, 7.1)

−8.6 (−39.8, 55.2)

Chromium, μg

699

0.67

−0.16

0.68

0.46

0.5 (0.3, 0.9)

−5.5 (−40.4, 52.1)

Molybdenum, μg

822

0.74

0.48

0.76

0.58

6.4 (3.5, 13.5)

−6.1 (−36.2, 48.5)

Retinol, μg

433

0.71

0.97

0.74

0.55

19.2 (5.1, 35.6)

−5.2 (−38.0, 74.3)

α-carotene, μg

412

0.86

0.16

0.85

0.73

107.0 (2.1, 194.5)

−19.3 (−49.4, 28.6)

β-carotene, μg

784

0.88

0.68

0.88

0.77

132.5 (29.1, 681.6)

3.7 (−37.9, 67.8)

Cryptoxanthin, μg

381

0.89

0.19

0.84

0.70

5.4 (2.0, 12.7)

−4.8 (− 37.1, 35.6)

Vitamin D, μg

512

0.93

−0.01

0.83

0.69

0.4 (0.2, 0.9)

−11.3 (−36.3, 39.4)

α-tocopherol, mg

1043

0.90

−0.07

0.89

0.79

0.4 (0.1, 0.9)

2.0 (−27.9, 40.3)

β-tocopherol, mg

544

0.84

−0.62

0.69

0.48

0.05 (0.03, 0.08)

−5.6 (−40.5, 56.6)

γ-tocopherol, mg

806

0.80

−0.08

0.85

0.72

1.1 (0.2, 2.2)

7.0 (−32.2, 55.2)

δ-tocopherol, mg

565

0.83

−0.33

0.79

0.63

0.4 (0.2, 0.6)

3.7 (−37.3, 48.6)

Vitamin K, μg

900

0.85

0.43

0.88

0.77

13.7 (4.8, 28)

−3.1 (−31.4, 36.6)

Vitamin B1, mg

1142

0.89

−0.24

0.89

0.79

0.05 (0.03, 0.10)

1.8 (−25.6, 42.5)

Vitamin B2, mg

1162

0.95

−0.03

0.93

0.87

0.06 (0.02, 0.14)

3.1 (−22.6, 37.1)

Niacin, mg

1162

0.90

0.04

0.92

0.84

0.8 (0.3, 2.3)

3.4 (−25.0, 39.1)

Vitamin B6, mg

1153

0.90

−0.22

0.89

0.80

0.06 (0.02, 0.15)

−0.4 (−27.1, 35.0)

Vitamin B12, μg

804

0.61

−0.37

0.56

0.31

0.4 (0.3, 0.6)

−15.9 (−42.3, 29.3)

Folate, μg

1135

0.85

0.51

0.89

0.79

18.5 (7.8, 32.6)

2.1 (−24.6, 40.6)

Pantothenic acid, mg

1140

0.90

−0.06

0.90

0.81

0.3 (0.1, 0.7)

1.0 (−24.6, 32.4)

Biotin, μg

831

0.84

0.14

0.78

0.60

2.3 (1.5, 3.9)

−0.2 (−32.2, 54.8)

Vitamin C, mg

800

0.81

0.46

0.83

0.69

6.8 (3.3, 14.1)

−4.0 (− 33.3, 51.9)

  1. SFA Saturated fatty acid, MUFA Monounsaturated fatty acid, PUFA Polyunsaturated fatty acid
  2. aPrediction Equation: Y = ea × (X)b, Y: directly weighed value, X: estimates based on a food-photographic record
  3. bPearson’s correlation coefficient between log weighed value and estimates from a food-photographic record
  4. cThe values of R2 indicate the percentage of the variance of log-Y accounted by equations
  5. d(Corrected value from a food-photographic record - weighed value)/(weighed value) × 100
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Nutrition Journal

ISSN: 1475-2891

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