Relative validity of the food frequency questionnaire used to assess dietary intake in the Leiden Longevity Study

Nutrition Journal

Table 3 Difference in food consumption and Pearson’s correlation coefficients between the FFQ and 24-hour recalls (N=128)

	FFQ		24-hour recall			Pearson's correlation coefficients
Food group	Mean	S.d.	Mean	S.d.	*p-value* ^a	Crude ^a	Adj ^a,b	Adj, deatt ^a,b,c
Potatoes (g)	90	57	104	61	0.88	0.25	0.21	0.50
Non-alcoholic beverages (g)	790	311	1631	601	<.0001	0.14^d	0.17^d	0.15^d
Bread (g)	126	55	133	54	0.002	0.79	0.71	0.93
Eggs (g)	12	10	13	17	<.0001	0.46	0.46	-
Fruit (g)	184	124	163	118	0.28	0.50	0.51	0.62
Pastry, cake and biscuits (g)	36	23	41	33	0.13	0.63	0.65	0.86
Cereal products and binding agents (g)	43	35	26	33	<.0001	0.41	0.40	-
Vegetables (g)	136	72	141	76	0.80	0.24	0.23	0.41
Savory sandwich fillings (g)	2	5	2	5	0.01	0.38	0.39	0.45
Cheese (g)	36	38	30	20	0.38	0.46	0.51	0.61
Milk and milk products (g)	311	221	328	223	0.27	0.69	0.68	0.75
Soya products and vegetarian products (g)	10	33	6	22	0.01	0.50	0.51	0.66
Nuts, seeds and snacks (g)	32	26	18	24	<.0001	0.24	0.25	0.40
Legumes (g)	8	11	2	9	<.0001	−0.02^d	−0.01^d	-
Composite dishes (g)	14	15	28	54	0.0001	0.10^d	0.10^d	-
Soups (g)	53	62	52	76	<.0001	0.31	0.30	0.66
Sugar, confectionary, sweet fillings and sweet sauces (g)	28	24	25	23	0.02	0.67	0.66	0.81
Fats, oils and savory sauces (g)	40	20	40	27	0.32	0.53	0.54	0.77
Fish (g)	14	14	19	40	<.0001	0.37	0.37	0.46
Meat, meat products and poultry (g)	75	34	94	48	0.02	0.56	0.56	0.98
Alcoholic beverages (g)	196	243	217	287	0.05	0.78	0.75	0.88

a = Based on log-transformed values; b = Correlation coefficients were adjusted for energy intake; energy-adjusted intakes were calculated using the residual method; c = Correlation coefficients were de-attenuated (corrected for within-person variation [derived from crude, untransformed data] in the 24-hour recalls); d = Correlation coefficients are not significantly different from zero.

ISSN: 1475-2891