Skip to main content

Table 2 Relative validity of the SFFQ for food groups (n = 127)

From: Validity and reproducibility of a short food frequency questionnaire among patients with chronic kidney disease

 

Daily intakes

 

Spearman correlation coefficients

Cross-classification of food group distributions

24-hour recalls

SFFQ 2

SFFQ2-24-hour recalls

SFFQ2 vs. means of six 24-hour recalls

 
 

Mean in grams (foods) or ml (beverages) (SD)

Means of differences, in grams (foods) or ml (beverages) (SD)

Unadjusted

% of subjects classified in same tertilea

% of subjects classified in same or adjacent quintile

% of misclassified subjects

Whole-grain bread and substitutesb

20.3 (40.3)

29.9 (53.3)

9.6 (64.3)

0.15

48

.

.

White bread and substitutes

83.3 (63.4)

93.2 (91.7)

9.9 (75.1)

0.49

51

73

2

Breakfast cerealsb

0.9 (6.0)

1.5 (6.1)

0.6 (5.6)

0.65

95

.

.

Whole-grain pasta, rice and wheatb

2.8 (18.4)

20.0* (35.1)

17.1 (32.4)

0.19

50

.

.

White pasta, rice and wheat

67.8 (58.9)

43.8* (45.9)

-24.0 (56.1)

0.39

47

66

2

Legumesb

7.0 (16.7)

26.9* (44.0)

19.8 (47.7)

0.05

24

.

.

French fries and other fried tubersb

8.3 (12.2)

11.1 (15.7)

2.8 (18.7)

0.17

34

.

.

Potatoes and other tubers (not fried)

61.0 (51.9)

52.5 (49.9)

-8.4 (62.6)

0.22

42

66

6

Cooked vegetables

229.2 (186.9)

107.6* (118.0)

-121.6 (196.0)

0.27

37

61

4

Raw vegetables

65.8 (45.1)

35.5* (38.4)

-30.3 (47.7)

0.42

50

66

3

Pizza, lasagna and quicheb

14.9 (26.7)

12.2 (21.0)

-2.7 (31.6)

0.24

38

.

.

Sandwich, burgers and kebabb

2.8 (16.0)

2.1 (7.1)

-0.6 (12.5)

0.41

86

.

.

Fish fingers/ breaded meatb

3.5 (8.7)

4.8 (12.4)

1.3 (13.9)

0.22

59

.

.

Sausages and other processed meat

33.7 (27.7)

23.6* (37.3)

-10.0 (40.0)

0.31

41

65

4

Poultry/rabbit

32.9 (28.5)

26.3* (36.4)

-6.6 (42.8)

0.24

43

61

5

Meat

52.2 (37.0)

37.1* (37.4)

-15.0 (46.9)

0.31

44

68

3

Offalb

3.4 (8.6)

2.8 (5.2)

-0.6 (9.7)

0.10

62

.

.

Eggsb

11.6 (14.4)

14.6* (13.2)

3.0 (16.5)

0.27

35

.

.

Fishb

46.1 (78.2)

16.0* (17.5)

-30.1 (78.1)

0.27

44

.

.

Seafood (excluding fish)b

9.6 (24.1)

3.3* (5.5)

-6.3 (23.8)

0.20

51

.

.

Milkb

60.6 (98.8)

118.6* (304.4)

58.0 (267.2)

0.77

65

.

.

Yoghurt, fromage blanc, cottage cheese

71.0 (64.2)

78.6 (74.3)

7.6 (63.7)

0.59

54

79

2

Cream dessertb

11.3 (25.9)

16.7 (31.6)

5.4 (31.4)

0.39

52

.

.

Cheese

33.0 (21.7)

30.2 (47.1)

-2.8 (47.5)

0.43

50

68

3

Butter, crème fraîcheb

6.3 (7.0)

10.3* (14.8)

4.0 (11.4)

0.59

49

.

.

Margarine, mayonnaiseb

3.7 (6.4)

5.0* (9.8)

1.3 (8.7)

0.54

62

.

.

Olive oilb

2.5 (3.7)

5.3* (7.0)

2.8 (6.4)

0.52

57

.

.

Rapeseed oil, walnut oil, mixed oilb

2.0 (3.0)

2.9 (4.7)

0.9 (4.7)

0.53

50

.

.

Sunflower oil, groundnut oilb

1.3 (2.5)

1.9 (4.5)

0.6 (4.0)

0.45

61

.

.

Salty snacksb

3.0 (6.7)

2.9 (6.7)

-0.1 (6.7)

0.35

57

.

.

Sweet snacks, chocolate and viennoiseriesb

38.6 (37.1)

21.0* (44.5)

-17.5 (50.8)

0.35

48

.

.

Fruit

270.1 (157.8)

295.9 (268.7)

25.8 (251.3)

0.41

47

69

4

Water

1201.0 (481.9)

982.2* (679.6)

-218.8 (641.7)

0.42

54

72

3

Coffee

267.9 (192.6)

387.8* (472.7)

119.9 (425.2)

0.61

61

76

2

Tea and herb teasb

93.1 (183.9)

124.3* (280.4)

31.2 (160.2)

0.79

74

.

.

Fruit juiceb

48.1 (79.6)

108.9* (294.4)

60.8 (272.9)

0.61

61

.

.

Sweet beveragesb

19.9 (64.9)

97.8* (500.9)

77.8 (487.6)

0.40

71

.

.

Artificially-sweetened beveragesb

18.6 (133.7)

72.1 (432.1)

53.5 (416.0)

0.48

89

.

.

Wineb

77.8 (125.7)

90.0 (156.7)

12.2 (105.1)

0.77

68

.

.

Other alcoholic beveragesb

40.0 (81.7)

34.9 (94.4)

-5.1 (93.9)

0.47

54

.

.

  1. *Significantly different from the value of the mean of the six 24-h recalls, according to Wilcoxon signed rank tests
  2. aFor food groups with a proportion of non-consumers > 20%b, tertiles and quintiles classifications were not performed. Instead, participants were classified as follows: class = 1 for null consumption; class = 2 for consumption below or equal to the median value in consumers, class = 3 for consumption above the median value in consumers
  3. bThese food groups have a large proportion of non-consumers (>20%)
  4. The statistical tests provided p-values <0.05 for each unadjusted Spearman correlation coefficient, except for those in bold
Back to article page

BMC Nephrology

ISSN: 1471-2369

Contact us