Development and relative validation of a food frequency questionnaire for French-Canadian adolescent and young adult survivors of acute lymphoblastic leukemia

Table 6 Food frequency questionnaires visit 1 and 2: cross-classification analysis of energy intake, nutrient intake and Mediterranean diet score

	% Classified into same quartile^a	% Classified into same ±1 quartile^a	% Misclassified^a	Weighted Kappa^b
Energy	44.8	41.4	13.8	0.60
Protein	37.9	48.3	13.8	0.57
CHO	48.3	41.4	10.3	0.66
Lipids	44.8	34.5	20.7	0.52
Vitamin A	48.3	27.6	24.1	0.49
Vitamin C	44.8	41.4	13.8	0.46
Vitamin E	51.7	31.0	17.3	0.52
Vitamin D	51.7	37.9	10.4	0.66
Calcium	51.7	34.5	13.8	0.63
Mediterranean diet score	58.6	27.6	13.8	0.68

Values are expressed in percentage, N = 29
^aCross-classification analyses were completed to validate agreement between the two FFQs in terms of proportions of participants classified into the same or same ±1 quartile or misclassified
^bWeighted kappa was used to measure the agreement between the two FFQs. Analyses were completed on crude values not adjusted for energy intake. CHO: carbohydrates

ISSN: 1475-2891